PNE UMATOMETPY: 
THE 
AEW MEANS OF DIAGNOSIS 
IX 
DISEASES OF THE RESPIRATORY ORGANS. 
\| BY 
LOUIS ELSBERG, A. M., M. 1)., 
PROFESSOR OF LARYNGOLOGY AND DISEASES OF THE THROAT IN THE MEDICAL 
DEPARTMENT OF THE UNIVERSITY OF THE CITY OF NEW YORK, FELLOW 
OF THE NEW YORK ACADEMY OF MEDICINE, ETC. 
LREPRINTED FROM THE NEW YORK MEDICAL JOURNAR-NOV.. 1875^ 
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D. APPLETON & 00., 549 & 551 Broadway, N. Y, PNELTM ATOMETRY: 
THE 
YEW MEANS OF DIAGNOSIS 
IN 
DISEASES OF THE RESPIRATORY ORGANS. 
BY 
LOUIS ELSBERG, A. M., M. IX, 
PROFESSOR OF LARYNGOLOGY AND DISEASES OF THE THROAT IN THE MEDICAL 
DEPARTMENT OF THE UNIVERSITY OF THE CITY OF NEW YORK, FELLOW 
OF THE NEW YORK ACADEMY OF MEDICINE, ETC. 
L HE Pit IN TED FROM THE NEW YORK MEDICAL JOURNAL, NOV., 1875.] 
NEW YORK: 
D. APPLETON & COMPANY, 
549 & 55 1 BROADWAY. 
1875. PNEUMATOMETRY: THE NEW MEANS OF 
DIAGNOSIS IN DISEASES OF THE RE- 
SPIRATORY ORGANS.1 
Definition.—Pneumatometry (from irvev/xa, air,” apper- 
taining to the breathing, and juerpov, “ measure,”) is the method 
of measuring inspiratory and expiratory force. For clinical 
purposes, the extreme respiratory power is measured which 
the patient is capable of exerting. This maximum, which is 
nearly constant for the same person in normal condition, varies 
characteristically in disease. The great value of pneumato- 
metry for diagnosis consists in the fact that each of the two 
phases of breathing, inspiration and expiration, can be meas- 
ured objectively and in figures, showing the deviation from 
health of either the one or the other separately, as well as the 
relation of the two to each other. 
History.—A century and a half ago the Rev. Dr. Hales 
engaged in some curious researches upon the air. In the 
course of his experiments, he had occasion to breathe out of 
and into closed air receptacles, and, being desirous of ascer- 
taining the force he could bring to bear, employed a mercury 
manometer. So far as I can find out, he is the first who en- 
tered upon such an investigation. The book in which he 
made it known was printed in 1726. Speaking of the use of 
bladders or leather bags filled with air, for temporarily sus- 
1 Road before the Academy, October 7th, 1875. 4 
taining respiration in a mom filled with suffocating vapors, in 
case of fire, for divers, etc., lie says: “ But in every apparatus 
of this kind great care must always he taken that the inspira- 
tion he as free as possible, by making large passages and valves 
to play most easily. For though a man by a peculiar action 
of his mouth and tongue may suck mercury 22 inches [about 
558 millimetres], and some men 27 or 28 [685 to 712 milli- 
metres] high, yet. 1 have found by experience that, by the bare 
inspiring action of the diaphragm and dilating thorax, I could 
scarcely raise the mercury two inches [50 millimetres]. At 
which time the diaphragm must act with a force equal to the 
weight of a cylinder of mercury, whose base is commensurate 
to the area of the diaphragm and its height two inches, where- 
by the diaphragm must at that time sustain a weight equal to 
many pounds. Neither are its counteracting muscles, those 
of the abdomen, able to exert a greater force. 
“ For, notwithstanding a man, by strongly compressing a 
quantity of air included in his mouth, may raise a column of 
mercury in an inverted syphon, to five or seven inches in 
height [126 to 178 millimetres], yet he cannot, with his utmost 
strainings, raise it above two inches [say 51 millimetres] by the 
contracting force of the muscles of the abdomen ; whence we 
see that our loudest vociferations are made with a force of an- 
no greater than this." 1 I have quoted this passage in full 
here, because it is very interesting as presenting the result of 
the first pneumatometric investigation, although, as we shall 
see hereafter, the figures given do not accord with those that 
have since been ascertained. 
Whether any one soon followed in the path of research thus 
opened up by Hales I do not know. More than a hundred 
years later, in 1844, Valentin published his text-book of “Hu- 
1 “ Statical Essays: containing vegetable staticks or an account of some 
statical experiments on the sap in vegetables, being an essay towards a 
Natural History of Vegetation: of use to those who are curious in the 
culture and improvement of gardening, etc., also a specimen of an attempt 
to analyse the Air, by a great variety of chymio-statical experiments, which 
were read at several meetings before the Royal Society. By Steph. Hales, 
I). D., F. R. S., Rector of Farringdon, Hampshire, and Minister of Tedding- 
ton, Middlesex. The third edition, with amendments.” London, 1738, 
vol. i., pp. 270 and 271. 5 
man Physiology,” and in it recorded his observations for deter- 
mining manometrically the respiratory power of an adult 
healthy man. To the apparatus employed he gave the name 
Pneumatometer; it was a modified haemadynamometer, and, 
simple as it was, the instrument was essentially the same as 
that in use at the present day.1 In 1845 Mendelsohn published 
some investigations in pneumatometry.2 In 1846 Hutchinson 
followed with a large number of elaborately conducted obser- 
vations and experiments.3 In 1853 Ponders added his valu- 
able contributions.4 
But notwithstanding the labors of these investigators— 
notwithstanding that the two last mentioned, Hutchinson and 
Ponders, had even particularly pointed out the fact of the im- 
portance of these researches for recognizing disease—all these 
publications remained barren of practical results for medicine 
until Waldenburg, less than four years ago, introduced the 
method of pneumatometry as a means of diagnosis.6 For 
eighteen months previous to that time Prof. Waldenburg had 
studied and tested the method, had demonstrated it in his 
courses to medical students, and had shown it to me during 
my stay in Berlin. 
The Instrument.—Waldenburg made the original instru- 
1 “Lehrbuch (ler Physiologie des Menschen.” Yon Dr. G. Valentin, 
ordentl. Professor der Physiologie nnd vergleichenden Anatomie an der 
Universitat Bern. Braunschweig, Friedrich Yievveg und Solin, 1844, vol. 
i., p. 524, et seq. 
2 “Der Meehanismus der Respiration und Circulation oder das expli- 
cirte Wesen der Lungenhyperamien.” Von A. Mendelsohn. Berlin, 
Behr’sche Buchbandlung, 1845. 
3 “ On the Capacity of the Lungs, and on the Respiratory Function, 
with a View of establishing a Precise and Easy Method of detecting Disease 
by the Spirometer; ” by John Hutchinson, Surgeon (with numerous Wood- 
cuts). “ Medico-Chirurgical Transactions,” published by the Royal Medi- 
cal and Chirurgical Society of London, vol. xxix. (second series, vol. xi.), 
London, 1846, pp. 137-252. 
4 “ Beitrage zum Mechanistnus der Respiration und Circulation itn 
gesunden und kranken Zustande.” Henle and Pfeufer’s Zeitschrift fur 
rationelle Medicin, V. F., Bd. iii., Heidelberg, 1853. 
6 “Die Manometrie der Lungen oder Pneurnatometrie als diagnostische 
Methode.” Von Prof. Dr. L. Waldenburg. Berliner lcUnwcJie Woehen- 
schrift, Jahrgang 8, Vo. 45, 1871, p. 541. 6 
ment of Valentin more convenient, and lias described and 
figured it in his latest publication on the subject.1 Eichhorst2 
has added to Walden burg’s apparatus an air-tight stop-cock, 
which I have replaced by an automatic valve. 
The pneumatometer, as I have had it constructed and rep- 
resented in the following woodcuts, consists of a glass tube, 
bent upon itself so as to have two parallel limbs, attached 
to an upright metal scale. One end of the tube is expanded 
to facilitate the pouring in of mercury; being in contact 
with-the atmosphere, it is covered, after sufficient mercury 
has been poured in, with gauze to prevent the entrance of 
dust; the other end is bent at a right angle, and with it is 
connected, in an air-tight manner, a rubber tube through 
which the breathing is accomplished. The scale has a zero- 
line in the middle and 125 millimetres above and below for 
each side of the glass tube. In addition to two fastenings 
which keep the glass in front of the metal, there is a slit be- 
low, in which slides a rest for it, controlled by a screw behind ; 
this facilitates getting the glass tube, after being about half 
filled with mercury, in the proper position upon the scale, viz., 
the level of the mercury in each limb of the tube being made 
to correspond with the zero-line. The breathing-tube leads, 
either with or without the intervention of the hard-rubber 
valve-tube (a in Fig. 1), to either nose or mouth-pieces (Fig. 2, 
and <?, d, in Fig. 1) or a nose-and-moutli-mask (J, in Fig. 1), all 
of which will be more particularly described presently. The 
foot of the pneumatometer is of wood, and about two inches 
high ; the upright metal piece about thirteen inches high and 
two inches wide; the glass tube nearly one-half inch thick. 
Both limbs of the glass tube should have exactly the same 
bore, so that the mercury in one rises exactly as much as it 
1 “ Die pnenmatische Behandlung der Respirations- und Circulations- 
krankheiten iin Anschluss an die Pneumatornetrie, Spiroraetrie und 
Brustmessung. Bearbeitet von Dr. med. L. Waldenburg, Professor E. O. 
an der Kgl. Friedrick-Wilhelms-Universitat in Berlin. Mit 30 Holzschnit- 
ten. Berlin, August Hirschwald, 1875. 
2 “ Ueber die Pneumatornetrie und ihre Anwendung fur die Diagnostik 
der Lungenkrankheiten.” Von Hermann Eichhorst aus Konigsberg. 
Deutsches Archie fur Hinische Medicin, Bd. xi., Heft iii., 1873, p. 268. 7 
Fig. 1. 
Fig. 2. 
falls in the other, for, as the pressure upon the column of mer- 
cury is measured by the difference in level in the two, it would 
be necessary to note the number of millimetres both above and 8 
below zero, and add these together, if the two portions were 
of different bore, instead of simply noting one number and 
doubling this, as can be done if the bore is uniform. The 
valve-tube is about 6 inches long, and in the middle 1 inch 
thick, gradually getting thinner toward the ends, with a bore 
of nearly inch. It is reversible, so as to answer for both 
inspiration and expiration. The single nose-piece is a hard- 
rubber nozzle, inches long, shaped so as to completely fill 
the nostril. Not more than two or three different nozzles are 
required for all the nostrils met with. The double nose-piece 
(Fig. 2) is a hard-rubber, hollow cylinder, inch in diameter 
and the same in length, connected at one end with two soft- 
rubber pipes, inches long, with inch bore, each terminating 
in a nozzle of hard rubber, like that of the single nose-piece, 
and at the other end attachable, either directly to the breathing- 
tube of the pneumatometer, or, by means of a short piece of 
India-rubber tubing, to the valve-tube. As a rule, I use the 
valve-tube; when it is desirable to ascertain how long the pa- 
tient can sustain a certain pressure at a certain point, I take it, 
off. Whenever the nasal passages are free for respiratory pur- 
poses, I use the double nose-piece; sometimes, when breath- 
ing is impeded through one nostril, the single nose-piece for 
the other nostril. As mouth-piece, I use either my valve- 
tube or a tube just like it without a valve. The oro-nasal 
masks I employ are the same as Waldenburg’s. They are hol- 
low hemispheres of sheet-brass or tin, with an indentation for 
the nose, the free edge being covered with India-rubber to make 
it fit air-tightly to the face, and the dome pierced by a short 
tube, £ inch in diameter, which can be attached either to the 
valve-tube, or directly to the breathing-tube. Three or four 
different sizes of masks are required, varying in diameter 
from 2|- to inches. 
The Mode of using the Instrument.—To carry out the meth- 
od of pneumatometry is exceedingly simple; nevertheless, it 
must be thoroughly studied and practised before it can serve 
the purpose of diagnosis. 
Upon breathing into the instrument, the pressure of the 
air upon the column of mercury with which it first conies into 
contact depresses the column, the mercury rises in the opposite 9 
limb of the glass tube, and the difference of level in the two 
limbs is the measure of the expiratory pressure exerted. This 
is the positive pressure. During inspiration, on the other 
hand, the mercury contained in the limb with which the 
breathing-tube is connected is sucked up, the column in the 
other limb falls correspondingly, and the difference in the 
levels of the mercury indicates the negative pressure of inspi- 
ration, which may be called the inspiratory traction. Thus, 
expiration yields us on the pneumatometer a positive, and in- 
spiration a negative pressure. 
In instructing the patient how to breathe, the very first 
question that must be met is, Shall he breathe through the 
nose, or mouth, or both % Hales seems to have used the month. 
Valentin employed three different methods, viz.: 1. lie applied 
a funnel-shaped mouth-piece, adapted to the form of the lips, 
air-tightly to the outside of the open mouth, closed both nos- 
trils, and had both inspiration and expiration performed several 
times without taking the mouth-piece off. But, as the air be- 
tween the lips of the patient and the column of mercury be- 
came, under these circumstances, soon unfit to sustain respira- 
tion, only the first few breaths were of any value. 2. He 
allowed inspiration through the open nose with closed lips, 
and measured only the expiration through the mouth-piece as 
before. 3. He varied the second method by having the nos- 
trils open during the expiration. Mendelsohn introduced a 
nose-tube tightly into one nostril, and closed the other nostril 
and the mouth. Hutchinson proceeded in the same way. 
Bonders had also both inspiration and expiration performed 
through the nose. Walden burg tested the same procedure, 
but dropped it entirely, except for the very rare cases in which 
he finds the patient intractable for other methods, or in which 
he wants to control the other methods by an additional one; 
he uses a mouth-piece, introduced very far into the mouth, if 
borne by the patient, to the very root of the tongue, beyond 
the isthmus glosso-palatinus, with the lips tightly closed 
around, or he uses, what he prefers, a mask covering air-tightly 
both nose and mouth, the patient breathing both in and out 
with his mouth widely open. Nearly all who have practised 
pneumatometrv since, have followed Waldenburg in preferring 10 
the mask. After experimenting a good deal with the mask, 
and with my nose-tnbes, I must confess that I think the latter 
more exact and unchanging in results, in all cases where 
freely applicable, i. e., where there is no obstruction to 
breathing by swelling, mucus, or otherwise, or where its use 
is not annoying to the patient. But Waldenburg’s method 
of breathing through the mask yields good results, and I fre- 
quently employ it—and also the mouth-piece—in conjunction 
with the method of breathing through the nose-piece. In cases 
of catarrh or obstruction of the nose, I frequently, also, place 
Waldenburg’s and my methods in juxtaposition, to determine 
the difference of the manifestation of respiratory power caused 
by the difficulty of breathing through the nose. Whenever 
the patient uses the nose-piece, he must keep the mouth 
shut. 
Like Eichhorst (op. cit.), I have found that the sources of 
error which Waldenburg has very properly pointed out, can 
be avoided by attention and properly instructing the patient. 
These sources of error arise from the powers of suction and 
expulsion that can be exercised by the muscles of the mouth 
and throat; from inattention on the part of the patient to what 
he is doing, in breathing out during intended inspiration, and 
in during intended expiration ; and from breathing irregularly 
and repeatedly in one effort. 
The breathings should be deep, and with the exertion ot 
all the power of which the individual is capable. Before 
breathing into the instrument, I let him till his lungs well. 
After each expiration, I give him a moment’s rest, during which 
he breathes naturally; he then takes a deep inspiration and 
makes another expiratory effort. The first few trials I hardly 
ever count. I show him just how to do it, and usually after 
the fourth or fifth experiment—-in the case of an exceptionally 
unteachable patient, not until after the tenth or twelfth—he 
a voids all sources of error. I then try him (after a rest, if he 
is weak) five or six times more, and note down the maximum 
pressure attained in any one of these successful efforts. 
These last live or six experiments, as a rule, give the same or 
nearly the same result, which I have found unvarying, even 
at repeated rests ax irregular intervals—a reasonably sure in- 11 
dication that it is pretty nearly correct. After finishing 
with the expiration, I proceed to measure the inspiratory 
power in a similar manner. Walden burg found, however, 
that it is immaterial whether an ordinary or a deep expira- 
tion precedes the inspiration to be measured, and I have 
come to hold the same opinion. 
In both phases of respiration, a difference can be made 
between a forcible effort and a slower, gradually increasing, 
but nevertheless as powerful, exertion. In the former, a 
greater pressure is attained for a moment, which sinks rapid- 
ly ; but, in the latter, the column of mercury can be sustained 
at a certain height for one or more seconds. As I usually at- 
tach to the pneumatometer my valve-tube, which maintains 
ttie pressure achieved, I make use of the former mode, which 
upon the whole is certainly preferable ; but occasionally I re- 
move the valve-piece, and measure by the other mode as well. 
The latter, of course, gives smaller and more complicated re- 
sults. 
I must give a caution in regard to reading the scale. I 
have already mentioned that the bore of the two limbs of the 
tube containing the mercury should be uniform, in order that 
the pressure be correctly attainable by simply doubling the 
number of millimetres above or below the zero-line indicated 
in either limb. Every one can easily ascertain whether in 
this respect his pneumatometer is trustworthy, by determining 
whether the level of the mercury is at exactly the same figure 
in each li nb. But the mercury, on account of its adhesion to 
the glass, has a convex surface in the tube, and care must be 
taken to note the tangential line. A mistake will certainly 
be made if the level of the observer’s eyes be either too high 
or too low. 
Immediately after a full meal, the respiratory power, espe- 
cially the expiratory, is usually diminished, and the measure- 
ment is not reliable. 
Pneumatometry in Health.—We have seen that Hales came 
to the conclusion that about 50 millimetres is the maximum 
attainable during inspiration “ by the bare inspiring action 
of the diaphragm and dilating thorax and also during pure 
expiration, even with the u utmost strainings.” He very 12 
properly excluded oral suction and expulsion as sources of 
error, but I suspect that his apparatus was not perfectly air- 
tight, and that therefore his figures are too low. Valentin 
obtained, in the cases of four different individuals, the follow- 
ing maxima: 1, deepest inspiration—130 millimetres, most 
forcible expiration +80 millimetres; 2, forced inspiration 
—232, forced expiration +256; 3, forced inspiration —220, 
forced expiration —|—256 ; 4, forced inspiration —58, forced ex 
piration -(-224. In later publications, Valentin reports still 
higher figures, viz.: —232 to —266 millimetres for inspira- 
tion, -(-260 to 326 millimetres for expiration.1 Waldenburg 
says, and I agree with him, that these figures are explicable only 
by assuming that instead of, or together with, inspiration, the 
aspiratorv power of the mouth, and instead of, or together 
with, expiration, the power of expulsion of the mouth, entered 
into the measurement. Mendelsohn found, as the mean of ex- 
periments on seven persons —87 millimetres for forced inspira- 
tion. and -(-113 to 122 millimetres for forced expiration, in 
the different individuals the inspiratory power varied from 
52 to 117 millimetres, the expiratory from 85 to 170 
millimetres. The expiratory pressure always exceeded the 
inspiratory traction, say, by about one inch, or 26 millimetres. 
These figures, it will be seen further on, agree very well with 
my own. Hutchinson obtained figures also very accurate, 
although his average is smaller than mine. He constructed 
a table on his instrument, of which he says, “Certain words 
are marked on the plate, their position having been determined 
by 1,500 experiments.” He gives his figures in inches, which 
I have calculated in millimetres, omitting fractions of a milli- 
metre under and reckoning fractions over as a whole 
millimetre: 
2 From the fourth edition of his “Grundriss der Physiologic,” Braun- 
schweig, 1855, as quoted by Waldenburg, “Die pneuniatischeBehandlung,” 
etc., p. 2. 13 
Inspiratory power rang- 
ing about: 
Cliaracterization. 
Expiratory power rang- 
ing about: 
38 millimetres. 
“ Weak.” 
51 millimetres. 
51 “ 
“ Ordinary.” 
63 “ 
63 
“ Strong:.” 
89 “ 
89 
“Very strong.” 
114 “ 
114 “ 
u Remarkable.” 
147 
140 “ 
“ Very remarkable.” 
178 
151 “ 
“ Extraordinary.” 
216 
178 “ 
“Very extraordinary.” 
254 “ 
lie adds, “It will be observed that the figures on each 
side of the same word differ in their value, the expiratory side 
ranging about higher, because the power manifested (I do 
not mean power exerted) by these muscular efforts varies in 
this relation.” This is certainly very frequently true, but oc- 
casionally the relation between the expiratory and inspiratory 
powers varies within very wide limits even in health, although 
the former is always greater than the latter. As an average, 
Hutchinson obtained about —76 millimetres for inspiration, 
and about 100 millimetres for expiration, for men. He does 
not seem to have determined the respiratory power of women. 
A certain relation exists, according to Hutchinson, between 
the height and the respiratory power, and he gives the follow- 
ing as the mean correspondence during health: 
Height 
Up to 5 ft. 
5 ft. 1 in. 
5 ft. 2 in. 
5 ft. 3 in. 
5 ft. 4 in. 
Inspiratory power in inches 
2.55 
2 
2.52 
2.31 
2.70 
Expiratory power in inches 
3.28 
3.30 
3.23 
3.15 
4.32 
Height 
5 ft. 6 in. 
5 ft. 7 in. 
5 ft. 8 in. 
5 ft. 9 in. 
Inspiratory power in inches 
....: 2.84 
2.70 
3.07 
2 90 
2.91 
Expiratory power in inches 
.... 4.33 
3.87 
4.18 
4.13 
4.28 
Height 
5 ft. 10 in. 
5 ft. 11 in. 
6 feet. 
Over 6 ft. 
Inspiratory power in inches 
2.83 
2.77 
2.65 
2.67 
Expiratory power in inches 
! 3.94 
3.63 
4.48 
4.41 
According to this, at the height of 5 feet 7 inches and 5 
feet 8 inches, the inspiratory power is greatest, and thence 
the strength gradually decreases as the stature increases. 14 
The men of 5 feet 7 and 8 inches elevate a column of about 
3 inches of mercury = 76 millimetres: this Hutchinson calls 
a “ healthy power.” The men of 6 feet have the greatest 
expiratory power, viz,, one of about 4|- inches = 114 milli- 
metres. But Hutchinson says, “ The expiratory power I 
do not consider such a test of strength, or, if I may be 
allowed the term, the vis vitce, as the inspiratory.” He refers 
here to the influence of vocation and habits upon the ex- 
piratory function. I have not been able to confirm this rela- 
tion between the height of a person and his inspiratory and 
expiratory power. Bonders published figures which are rather 
small; like Valentin, Mendelsohn, and Hutchinson, he found 
the expiratory power to exceed the inspiratory. He gives 
the negative pressure, for forced inspiration, as being from 
36 to 74 millimetres, the positive pressure, for forced expira- 
tion, from 82 to 100 millimetres. 
Walden burg declares, as the result of his numerous obser- 
vations., that the figures vary within wide limits : “ Healthy 
adult men, who are not especially strong, reach on the aver- 
age, by forced inspiration, a negative maximum pressure of 
80 to 100 millimetres, by forced expiration, a positive maxi- 
mum pressure of 100 to 130 millimetres. Very strong mus- 
cular men often considerably exceed these figures; they 
may attain by inspiration to from 120 to 160 millimetres, by 
expiration to from 150 to 220 millimetres. Weak persons, 
on the other hand, give lower rates; however, if they are 
healthy, we may regard for adult persons of the male sex 
70 millimetres as the minimum negative, or inspiration, press- 
ure, and 80 millimetres as the minimum positive, or ex- 
piration, pressure. Women can reach only considerably 
lower rates than men. With them, on an average, the nega- 
tive pressure of forced inspiration amounts to from 60 to 80 
millimetres, the positive pressure of forced expiration to from 
70 to 110 millimetres. Higher figures are reached only by 
few. In the case of healthy women, about —50 millimetres 
may be regarded as the minimum for forced inspiration, —|—60 
millimetres for forced expiration. Children of the age of 
about ten years and over usually show rates which correspond 
entirely, or nearly (with a difference of perhaps 10 to 20iuilli- 15 
metres), to the minimum of adults. Not a few children, in- 
deed, reach the average of adults. I have, however, not a suf- 
ficiently large number of observations to be able to give exact 
figures for children of the various ages. The same is true of 
very advanced age. Here, I can state only this, that in the 
case of old men (sometimes, indeed, already at an age of be- 
yond sixty years) the pneumatometrical figures fall to near 
the minimum, or even below this. All these numbers refer 
to the maxima obtained by forcible inspiration and expiration. 
The figures are much smaller for the more slow inspiration 
and expiration, gradually increasing in power, with which the 
person is able to maintain the pressure at the height for one 
or more seconds. With healthy adult men, the force of in- 
spiratory traction observed in this manner varies from 50 
millimetres to, at the most, 120 millimetres, the expiratory 
pressure from 60 to 150 millimetres; the mean values are, for 
inspiration, 60 to 90 millimetres, for expiration, 70 to 100 
millimetres. With women, inspiratory traction reaches some 
25 to 60 millimetres, expiratory pressure, 30 to 80 millime- 
tres.”1 Waldenburg’s figures closely, upon the whole, cor- 
respond to those which I have obtained by the examination 
of healthy persons; the extremes are within nearly the same 
limits, and I regard his results as very reliable. Eichhorst’s 
figures (op. cit.) are smaller than Waldenburg’s and mine, 
but he practised the mode of slow and gradual, though deep, 
rather than quick and forcible, respiration. His averages, 
obtained from twenty-four men, are 44 millimetres for inspira- 
tion, 60 millimetres for expiration ; from eighteen women, 26 
millimetres for inspiration, 36 millimetres for expiration. 
His lowest figures among men are, for inspiration, 17 milli- 
metres (found in two cases, one a laborer fifty-one years old, 
with expiratory power of 35 millimetres, the other a merchant 
fifty-two years old, with expiratory power of 26 millimetres), 
for expiration, 26 millimetres (the case of the merchant just 
mentioned); among women, for inspiration, 11 millimetres 
(in a laborer’s widow, fifty-three years old, whose expiratory 
power is given as 25 millimetres), for expiration, 25 millimetres 
(found in the case of this widow, and in that of a servant-girl 
1 “ Die pneumatische Behandlung,” etc. (op. cit.), p. 27. 16 
of nineteen years, whose inspiratory power was 24 milli- 
metres). H is highest figures among men for inspiration are 
86 millimetres (in the thirteen-years-old son of a shoemaker, 
whose expiration measured 91 millimetres), for expiration, 94 
millimetres (in a student aged twenty-three years, whose in- 
spiratory power was 82 millimetres); among women, for in- 
spiration, 42 millimetres (in a girl of sixteen years, who 
worked in a factory, whose expiration measured 47 milli- 
metres), for expiration, 55 millimetres (in a laboring woman, 
fifty-one years old, whose inspiration reached only 25 milli- 
metres). Lassar,1 who measured, not the maximum respira- 
tory power of which the individual was capable, but took the 
average of a number of experiments, gives as the average of 
such averages, for breathing through the mouth, 50 milli- 
metres for forced inspiration, and 60 millimetres for forced 
expiration ; for breathing through one nostril, for forced 
inspiration, 41 millimetres, for forced expiration, 52 milli- 
metres. 
The result of my own investigations of pneumatometry in 
over 100 healthy persons is,briefly stated, as follows: For the 
male sex, the average of the maximum inspiratory power is 
— 86 millimetres, the average for the maximum expiratory 
power -f-1 10 milli meters ; for the female sex, the average of the 
maximum of forced inspiration —50 millimetres, that of the 
maximum of forced expiration —|—T0. The highest figures I 
have met with in strong, healthy men are 170 millimetres for 
inspiration, and 230 millimetres for expiration. This is very 
exceptional, however. The maxima I have observed in healthy 
women—found also only very rarely—are 90 millimetres for 
inspiration, and 120 for expiration. The minimum of respira- 
tory power compatible with perfect health in women, I am 
forced to place much lower than Waldenburg has done ; as to 
men I am disposed to agree to his minimum figures, although 
all the healthy adult males that I have examined showed 
greater power than he gives as the minimum met with. I 
have full records of twenty-five individuals of each sex, sub- 
1 “ Zur Manometrie der Lungen. Inaugural-Abhandlung, der medi- 
cinisclien Facultiit zu Wurzburg vorgelegt.” Wurzburg, 1872. Walden- 
burg, “ Die pneumatiscbe Behandlung,” etc., p. 28. 17 
jectively in perfect health, who have been carefully clinically 
examined, more especially as to the condition of the respira- 
tory organs, but really also as to the condition of other organs, 
stating age, occupation, habits, build, weight, height, trunk 
measurements and lung capacity (vital ratio), physical signs 
on examination of chest, previous history and present state in 
other respects, and respiratory power as shown by the pneu- 
matometer. These records show that an adult woman may 
enjoy perfect health and yet not be able to reach on the pneu- 
matometer a higher figure than —20 millimetres as the maxi- 
mum for forced inspiration, and -(-30 millimetres as that for 
forced expiration. The lowest figures yielded by any one of 
the twenty-five healthy males were those of a strong, florid- 
complexioned gentleman of fifty-tliree years, viz., —74- milli- 
metres inspiration, and 86 millimetres expiration. 
With healthy children under ten years I have had very 
little experience. A boy of eight years has registered —50 
for inspiration, and 70 for expiration ; and a little girl of seven, 
very strong, however, for her age, —36 for inspiration, and 
between 40 and 50 for expiration. These are the highest fig- 
ures reached. Children over ten years usually exhibit almost 
the same latitude ami nearly the same figures as adults. In 
old age the figures often become surprisingly small. ' As a 
rarity I must mention the case of a hale and hearty gentleman, 
seventy-five years of age, who registered —112 millimetres for 
inspiration, and 130 millimetres for expiration. 
I will add Prof. Waldenburg’s respiratory power as shown 
by the pneumatometer, reported by himself, and my own : 
I. Waldenburg’s vital lung capacity : 3,000 cubic centi- 
metres. 
A. Breathing through a mouth-piece. 
1. Inspiration. 
a. Quick, forced inspiration. The mercury rapidly rises in 
one limb of the glass tube to 70 millimetres above zero, but 
sinks at once and keeps playing about a much lower point. 
The maximum inspiratory power is, therefore, —140 milli- 
metres. 
b. Slower, but the deepest possible, inspiration. The neg- 
ative pressure increases slowly until it reaches 100 millimetres, 18 
then falls to 80 millimetres, and for two seconds varies from 
40 to 80 millimetres and from 50 to 70 millimetres. The 
average number is, therefore, 60 millimetres, and about this 
point, indeed, the mercury remains longest. 
2. Expiration—after deep but not strained inspiration. 
a. Quick, forced expiration. The maximum pressure at- 
tained for a moment amounts to 150 millimetres. 
b. Slowly-increasing, powerful expiration. The pressure 
of 100 millimetres is reached, then the column of mercury 
falls and pendulates up and down, indicating for four seconds 
from 60 to 80 millimetres, and about half that time a few 
millimetres above or below 70 millimetres. 
The measures of inspiration, as well as of expiration, are 
the same whether the nose is closed or not. 
B. Breathing through a nose-piece [through one nostril]. 
1. Inspiration. 
a. Quick, forced inspiration. For a moment a negative 
maximum pressure of 140 millimetres is attained with imme 
diate falling of the mercury. 
b. Slow, very deep inspiration. After reaching 100 milli- 
metres, falling and pendulating of the mercury for three sec- 
onds at from 40 to 80 millimetres. Average 60 millimetres. 
The figures are the same, whether the second nostril re- 
mains open or is closed with the finger. The nostril closes 
involuntarily of itself during the inspiration. 
2. Expiration—after deep but not strained inspiration. 
a. Quick, forced expiration. Maximum reached for a mo- 
ment 170 millimetres. 
b. Slow, profound expiration. The pressure rises to 100 
millimetres, varies for two seconds between 100 and 70 milli- 
metres, and then remains for two seconds longer at 70 milli- 
metres. 
Throughout this experiment the second nostril was closed 
with the fingers. In other experiments, during which it had 
been left open, the numbers obtained were very much smaller 
and indeed useless, on account of the unimpeded egress of air 
through it. The maximum of expiratory power with open 
nostril amounted to only 110 millimetres. 
C. Breathing through the mask. 19 
1. Inspiration. 
a. Forced, quick inspiration. Maximum, for a moment, 
—130 millimetres. Rapid fall. 
b. Slower, deep inspiration. The negative pressure in- 
creases slowly to about 100 millimetres, then trembling move- 
ments of the mercury indicate from 50 to TO millimetres for 
one and a half second. Mean: --60 millimetres. 
2. Expiration after deep but not strained inspiration. 
a. Quick, forced expiration. For a moment 140 millime- 
tres pressure is reached ; mercury falls quickly. 
b. Slower, strong expiration. Hovering of the mercury, 
for one and a half second, between 60 and 80 millimetres. 
Mean : TO millimetres, 
II. As to myself (data of over a year ago), age thirty- 
eight years; strong and muscular; weight, without clothes, 15T 
lbs.; height (tive feet seven and three-quarters inches), 1T2 cen- 
timetres ; height of trunk, measured from seventh cervical 
vertebra to end of coccyx, 66 centimetres ; periphery, measured 
about 3 centimetres below nipple, 81 centimetres; vital lung 
capacity, 4,300 cubic centimetres (vital ratio, i. e., the rela- 
tion of the u vital lung capacity ” to the cubic contents of the 
trunk, 8.02); lungs healthy. 
A. Breathing through a mouth-piece. 
1. Inspiration. 
a. Quick, forced inspiration. Maximum negative pressure 
110 millimetres, with rapid sinking of the mercury. 
b. Slow, deep inspiration. Mercury sustained for three 
and a half seconds between 40 and 60 millimetres negative 
pressure. Mean ; —50 millimetres. 
2. Expiration after deep but not strained inspiration. 
a. Quick, forced expiration. Maximum, reached but for 
a moment, 130 millimetres. 
b. Slow, unexcited, but powerful expiration. The mer- 
cury kept for over three seconds between 60 and 80 millime- 
tres, longest about the mean of these figures, viz. : TO milli- 
metres. 
ISTo difference is observed in these results whether the nose 
is held shut or not. 
B. Breathing through my double nose-piece. (For con- 20 
venience of experimenting, breathing out was accomplished 
through the month when testing the inspiration, and breath- 
ing in when testing the expiration, which, it was found, did 
not disturb the mercury.) 
1. Inspiration. 
a. Quick, forced inspiration. Maximum —130 millime- 
tres, reached with quick descent and oscillation of the mercury. 
b. Slow and deep inspiration. A pressure of —120 mil- 
limetres is registered for a moment, and one of from —80 to 
—40 millimetres kept up for several seconds; most of the 
time about 60 millimetres. 
2. Expiration after deep but not strained inspiration. 
a. Quick, forced expiration. Maximum obtained, 150 mil- 
limetres. 
b. Slow and powerful expiration. A pressure of 100 milli- 
metres for an instant, one of 90 for a little longer, and a vary- 
ing one from 50 to 80 millimetres for two and a half seconds 
is reached. 
C. Breathing through the mask. 
1. Inspiration. 
a. Quick, forced inspiration. Maximum —130 millime- 
tres. 
b. Slow and deep inspiration. After the negative pressure 
of 120 millimetres has been just touched, it plays about —60 
millimetres as a central point for nearly two seconds, varying 
from 10 to 15 millimetres above and below. 
2. Expiration after deep but not strained inspiration as 
before. 
a. Quick, forced expiration. Momentary maximum press- 
ure, 150 millimetres. 
b. Slow, strong expiration. The mercury, slowly descend- 
ing, marks for more than two seconds a pressure varying from 
60 to 80 millimetres. 
Pneumatometry in Disease.—We have seen that in the 
normal condition the positive or expiration pressure is greater 
than the negative or inspiration pressure. We have also seen 
that, although the latitude of variation within the limits of 
health is a very great one, we still recognize for each sex a 
certain normal average and requisite minimum of inspiratory 21 
and expiratory power. Upon these considerations Walden- 
burg based his division and classification of the pathologi- 
cal breathing revealed by the pneumatometer. He made 
two groups, each of which he subdivided into three classes, 
viz.: 
Group I.—Characterized by the inversion of the normal 
relation between expiratory and inspiratory pressure; the 
positive pressure is smaller than the negative—there is an 
insufficiency of expiration. 
Class 1.—"With the insufficiency of expiration, the inspira- 
tory pressure is normal. 
Class 2.—With the insufficiency of expiration, the inspira- 
tory pressure does not reach the normal minimum; inspira- 
tion is therefore also insufficient; nevertheless, the expiratory 
pressure is still less than the inspiratory. 
Class 3.—With the insufficiency of expiration, the in- 
spiratory pressure is larger than normal. 
Group II.—Characterized by insufficiency of inspiration, 
the normal relation between expiratory and inspiratory press- 
ure being preserved; the negative pressure is smaller than 
the positive. 
Class 4.—With the insufficiency of inspiration, the expira- 
tory pressure is normal. 
Class 5.—With the insufficiency of inspiration, the ex- 
piratory pressure, although larger than the inspiratory, does 
not reach the normal minimum; expiration is therefore also 
insufficient. 
Class 6.—With the insufficiency of inspiration, the expira- 
tory pressure is larger than normal. Walden burg has added 
this class for the sake of completeness, admitting that he has 
never seen a case in point. It is difficult to conceive of a dis- 
ease bringing about such a condition unless, perhaps, where, 
with normal inspiration, the expiratory power has become 
preternaturally strong through habits, vocation (that of 
“glass-blower, trumpeter, wwestler ”), and the like, and dis- 
ease should then interfere with inspiratory power and leave 
the expiratory at first still greatly in excess; thus Hutchinson 
reports the case of a wrestler in whom he found “ the expira- 
tory power exceed nearly four times that of the natural in- 22 
spiratory power, which vast preponderance was purely the 
effect of his favorite amusement.” 
As Waldenburg has shown, the inspiratory traction as 
well as the expiratory pressure is a product of various factors, 
some of a positive, some of a negative character. These factors 
are: 1. The muscular power. 2. The elasticity of the lungs. 
3. The obstacles presented by the walls of the chest, its contents 
and their surroundings. 
“ In inspiration, the set of muscles brought into action for 
forcibly breathing air into the lungs forms the only positive 
factor. The muscular force has, on the one hand, to work 
against the elasticity of the lung-tissue which opposes expan- 
sion ; on the other hand, it lias to overcome the obstacles to 
change in the form of the thorax. These obstacles are princi- 
pally the force of gravity of the thoracic wall which has to be 
overcome in raising the ribs; the change of form and position 
to which the thorax and its contents—lungs, heart, vessels, 
and pleura—are exposed by expansion of the chest; the elas- 
ticity of the walls of the thorax; the difference of pressure 
between the outer atmosphere and the somewhat rarefied air 
within the lungs; and, finally, the abdominal tension resisting 
the lowering of the diaphragm. 
“ The case is different in expiration. Of course, the mus- 
cles coming into action for forcibly breathing air out form the 
main factor of the pressure produced. But the obstacles to 
inspiration are also active in favor of expiration. The pul- 
monary elasticity is an aid to expiration, increasing its power. 
Gravity also, and the other obstacles, directly aid expiration, 
as the parts disturbed tend of themselves to return to their 
former position. Only in very forced expiration—when the 
thorax is compressed beyond its former or balanced condition 
—new obstacles arise, expiratory obstacles in contradistinc- 
tion to inspiratory obstacles, while the elasticity of the lungs 
still continues to act in favor. Thus, in inspiration, the 
muscular power forms the positive, the elasticity of the lungs 
and the obstacles the negative, factors • while in expiration all 
these three factors are positive ones, with only a relatively 
small negative one from expiratory obstacles.'’'’1 
1 “ Die pneumatische Behandlung,” etc., pp. 53, 54. 23 
Waldenburg has laid down the following general propo- 
sitions : 
1. By muscular atrophy or diminution of muscular strength, 
the pneumatometrical figures are reduced, the inspiratory and 
expiratory about equally if the disease of the muscles be gen- 
eral ; but the former or the latter alone, or one more than the 
other, if the disease affect only single groups of muscles, es- 
pecially subservient more to either inspiration or expiration. 
Cceteris paribus, an increase of muscular power increases in 
like manner the figures registered on the pneumatometer. 
2. A diminution of the elasticity of the lungs reduces the 
pressure of expiration and tends to increase the negative press- 
ure of inspiration. 
3. An increase of inspiratory obstacles reduces the power 
of inspiration and increases that of expiration, in case ex- 
piratory obstacles are not present at the same time. But, on 
the other hand, there may appear expiratory obstacles, while 
the inspiratory obstacles are not at all or only slightly in- 
creased. In such cases the expiratory power alone, or mainly, 
will be reduced. 
Hutchinson says, “As it is a common rule that inflam- 
mation and disease in general are attended with pain on 
pressure, these also may be perceived by the diminished 
power manifested on the instrument which measures the 
pressure exerted.” He then gives a table showing the dif- 
ference between the inspiratory power of the healthy and 
that of the diseased, and adds, “ This difference is about one- 
half, as might be anticipated, because weakness is the most 
prominent symptom of disease.” 1 
Among the individual diseases, in obscure or incipient 
cases of which pneumatometry has furnished most important 
aid in diagnosis, pulmonary emphysema and phthisis must 
first be named ; but it has already been called into requisition 
not only in other diseases of the respiratory organs, but also 
in diseases of the circulatory and other organs. 
I. Diseases of the Respiratory Organs. 1. Pulmonary Em- 
physema.—Bonders already has pointed out that vesicular 
emphysema must be accompanied witli diminution of pul- 
1 Op. cit., pp. 225, 226. 24 
monary elasticity. Waldenburg lias discovered and demon- 
strated that pneumatoinetry is a means with which we can 
detect emphysema in its incipient stage, while yet all other 
methods of examination fail; this, too, even when no actual 
subjective disturbances exist at the time; and, moreover, pneu- 
matometry enables us to distinguish with probability between 
the various forms or stages of emphysema. In all cases there 
is dilatation of the terminating vesicles of the lungs, and 
“ either an abnormal accumulation of air within the air-cells, 
or an infiltration of air into the sub-pleural and interstitial con- 
nective tissue.” 1 The various forms or rather stages come all 
under the head of Waldenburg’s first group of pathological 
breathing, viz., that characterized by the inversion of the nor- 
mal relation between expiratory and inspiratory pressure; the 
positive pressure is smaller than the negative, there is insuffi- 
ciency of expiration. The incipient stage or slightest degree 
of the disease belongs to the first class, i. e., with little or 
much insufficiency of expiration, the inspiratory pressure is 
normal; the most severe form belongs to the second class, 
when, together with the insufficiency of expiration, the inspira- 
tory pressure, also, does not reach the normal minimum, i. e., 
when inspiration is also insufficient, though nevertheless the 
expiratory pressure is still less than the inspiratory; while the 
cases belonging to the third class, where with the insufficiency 
of expiration the inspiratory pressure is larger than normal 
(which, however, is more difficult, if not impossible, to deter- 
mine, unless the patient’s inspiratory power has been exam- 
ined during health and known for comparison), constitute the 
compensatory form, and may be ranged as to severity between 
those of the first and second classes. 
I could append a large number of cases both from my 
own experience and those reported by others, but I will only 
mention, exceedingly briefly, a few illustrative cases : 
L. P., aged forty years; merchant; complains of dyspnoea 
on any unusual exertion. This has probably occurred for 
'“Lectures on Diseases of the Respiratory Organs, Heart, and Kid- 
neys.” By Alfred L. Loomis, M. D., Professor of Pathology and Practi- 
cal Medicine in the Medical Department of the University of the City of 
New York, etc., etc. New York : William Wood & Co., 1875, p. 79. 25 
years, but increased so gradually that he hardly noticed it 
until the last two or three months. No cough, no expectora- 
tion. Inspection, percussion, and auscultation, reveal noth- 
ing abnormal. Health otherwise excellent. Pneumatometer 
showed inspiration —120 millimetres, expiration 92 millime- 
tres. 
H. S., aged thirty-live years; broker. Has had a cough 
off and on for over live years; is out of breath very easily on 
walking fast, going up-stairs, etc. Lungs extend lower down 
than normally, and heart, partly covered, is pushed downward 
and toward middle line. Respiratory murmur enfeebled, 
expiration-sound prolonged, some u rustling.” Inspiratory 
power —130 millimetres, expiratory 70 millimetres. 
W. II., aged fifty-two years. Has greatly suffered from 
shortness of breath on exertion ever since he can remember, 
much worse during the last year. Dilatation of the chest 
very marked, “ barrel-shaped ; ” percussion-sound abnormally 
clear, “ vesieulo-tympanitic ; ” auscultation-sound almost sup- 
pressed, sibilant in many places. Inspiration —40 millimetres, 
expiration 30 millimetres. 
Mrs. R., aged thirty-eight years. Previously remarkably 
healthy; has suffered from dyspnoea on exertion for three 
years. Has had to give up singing. Now suffers from great 
oppression each time she walks a few steps. Heart covered, 
liver pushed down; harsh vesicular breathing. Inspiration 
— 20 millimetres, expiration 16 millimetres. 
2. Asthma.—Emphysematous persons are so liable to at- 
tacks of asthma, and asthma, when it comes itself frun 
other causes, is so apt, perhaps so certain, sooner or later to 
produce emphysema, that the results of pneumatometry in 
asthmatic patients may frequently be ascribed to the coexist- 
ence of emphysema. But, independently of the latter, there 
exists during the paroxysm an expiratory insufficiency which 
the pneumatometer registers for some time thereafter, as in a 
case of seemingly uncomplicated spasmodic asthma in a man, 
twenty-eight years old, whose inspiration measured during the 
interval —50 millimetres, expiration 34 millimetres. 
3. Bronchitis.—We can say of bronchitis—at all events, 
of chronic or frequently-recurring bronchitis—that it is very 26 
frequently associated with pulmonary emphysema, and that it 
must, then, exhibit the pneumatometrical measures peculiar to 
the latter; but in many cases where this is to be excluded, as, 
for instance, in some cases of acute bronchitis, both primary 
and secondary, we also find insufficiency of the expiration. 
Waldenburg explains this by assuming that by narrowing of the 
smallest bronchioles on the one hand and pulmonary hyperse- 
mia on the other, the expiratory pressure is in such cases inter- 
fered with, wdiile the inspiratory remains unaffected. At all 
events, he and Eichhorst report cases in point, and I will add 
the following: J. B., a middling-strong man, in somewhat 
impaired health, however, for some time, took a very severe 
cold, with the symptoms of acute bronchitis. Auscultation 
revealed rather feeble respiratory murmur and sibilant rales. 
He has a frequent, hacking cough, which gives him a sense of 
rawness in the upper portion of the chest. Inspiratory power 
— 86 millimetres, expiratory 60 millimetres. 
4. Pulmonary Phthisis. — Hutchinson, who has made 
many hundred pneumatometrical observations on persons suf- 
fering from disease, has left us the following record of what 
he found in some cases of consumption : 
Case I.—Incipient phthisis. Age, thirty years; weight, 
ten stone three pounds; height, five feet eight inches; pulse 
while sitting, 100; number of respirations per minute while 
sitting, 28; circumference of chest, 36 inches; mobility of 
chest, inch ; vital capacity, 186 cubic inches ; power of in- 
spiration 0.70, of expiration 0.80 inch = inspiratory power 
—18 millimetres, expiratory 20 millimetres. 
Case II.—Phthisis. Age, sixty years; weight, ten stone ; 
height, five feet eleven inches ; pulse while sitting, 60; respira- 
tions per minute, sitting, 40 ; circumference of chest, inch- 
es ; mobility, inch; vital capacity, 108 cubic inches; power 
of inspiration 0.75, power of expiration 0.46 inch = inspira- 
tory power 19 millimetres, expiratory 12 millimetres. 
Case III.—Phthisis. Age, thirty-six; weight, ten stone; 
height, five feet nine inches; pulse sitting, 100; respirations 
per minute, sitting, 40; circumference of chest, thirty-five 
inches; mobility, one inch; vital capacity, 80 cubic inches; 27 
power of inspiration 1.50, of expiration 2 inches = inspiratory 
power —38 millimetres, expiratory 50 millimetres. 
Case IY.—Phthisis. This is the case of Freeman the 
“ American Giant,” and in it the pneumatometer as well as the 
spirometer indicated u the commencement of the disease which 
ultimately caused his death, and that before the usual means 
availed.” I shall quote the full details which Hutchinson re- 
lates, viz.: “ This man came over to England in 1842, and in 
the November of that year trained for a prize-fight; I examined 
him immediately before his professional engagement, when he 
might be considered in the ‘ best condition.’ Ilis powers 
were as follows: vital capacity four hundred and thirty-four 
cubic inches; height 6 feet inches; weight nineteen stone 
and five pounds ; circumference of his chest forty-seven inches ; 
inspiratory power 5.0 inches; expiratory power 6.5 inches. 
In November, 1844, exactly two years afterward, he came to 
town in iil-health. I then examined him in the same way as 
before, twenty times at various intervals, during which his 
vital capacity varied from 390 down to 340, and the mean 
of all the observations was 344 cubic inches, a decrease of 
ninety, or more than twenty per cent., his respiratory power 
had decreased one-fiftli, and his weight two stone. At this 
time I took him to two physicians well skilled in auscultation, 
and they both affirmed that they could not detect any organic 
disease. After January, 1845, I lost sight of Freeman, and in 
the October following I was kindly favored with the fol- 
lowing account of him from Mr. Paul, surgeon to the County 
Hospital, Winchester: ‘Freeman was admitted into this hos- 
pital on the 8th of October, in an extreme state of debility 
and exhaustion; he was reduced almost to a skeleton, com- 
plained of cough, and was expectorating pus in large quanti- 
ties. Percussion on the anterior part of the chest, under the 
clavicles, gave on the right side a very dull sound ; on the left 
one much clearer, but still, I think, less resonant than natu- 
ral ; I made but one attempt at auscultation, but could come 
to no conclusion, from a rather singular reason : the ribs were 
so large, the intercostal spaces so wide and so sunk in from the 
extreme state of emaciation to which Freeman was reduced, that 
I could not find a level space large enough to receive the end 28 
of the stethoscope ; could not, in short, bring its whole surface 
into contact with the chest. Freeman’s great debility and the 
clearness of diagnosis from other sources prevented my re- 
peating the attempt. Freeman, after death, measured 6 feet 
inches and weighed ten stone and one pound. On opening 
the chest, tlie lungs on both sides were found adhering by 
their apices to the superior boundaries of the thorax, and 
studded throughout their substance with tubercles. The tu- 
bercles, on the whole, were much less numerous in the right 
lung than in the left; both lungs were nearly healthy at their 
base ; the tubercular matter gradually increased in quantity 
toward their upper part, and the apices of both lungs were 
almost completely occupied by large cavities, partly filled with 
pus, and capable of containing two or three ounces of fluid 
each. The heart was remarkably small. The rest of the vis- 
cera appeared healthy.’ ” 1 In this case, the inspiratory power, 
from having been 127 millimetres during health, had become 
reduced to about 100 millimetres at a time when percussion and 
auscultation did not yet reveal any change. 
In his first publication on the subject, already, Walden- 
burg stated that in phthisis the inspiratory pressure becomes 
at once diminished, while the expiratory, usually, for some 
time nearly normal, is more slowly lessened and remains 
larger than the inspiratory. The breathing of phthisical pa- 
tients belongs, therefore, to the second group, viz.: that char- 
acterized by insufficiency of inspiration, the relation between 
expiratory and inspiratory pressure being normal, the negative 
smaller than the positive. This is so entirely different from 
what the pneumatometer shows in bronchitis and emphysema 
that it is of great value for differential diagnosis in doubtful 
cases, especially of incipient phthisis. As the disease .ad- 
vances and involves more and more of the lung-tissue, the 
negative pressure becomes smaller and smaller, in extreme 
cases sinking to most insignificant values. At the same time 
the positive pressure diminishes, preserving its relation ; but, 
though continuing to preponderate, it, too, becomes very 
greatly reduced; in severe cases to 10 millimetres, and even 
1 Op. cit., p. 219. 29 
below this figure. Waldenburg and Eicbhorst have reported 
numerous cases. I have a large number in my books, from 
which I will transcribe the following, omitting all details : 
S. D., aged thirty years. Phthisis, first stage, right apex 
posteriorly. Inspiration —60, expiration 100 millimetres. 
Miss F., aged twenty-three years. Phthisis, first stage, 
both apices (haemoptysis several years ago). Inspiration —18, 
expiration 36 millimetres. 
E. B., aged forty-two years. Phthisis, evidences of soft- 
ening. Inspiration —30 millimetres, expiration 50 millime- 
tres. 
Mrs. D., aged twenty-seven years. Phthisis. Softening; 
haemorrhages. Inspiration —14 millimetres, expiration, 20 
millimetres. 
J. L. S., aged thirty-five years. Advanced phthisis. In- 
spiration — 10, expiration 20, which changed to 16 in less 
than two weeks. 
Mrs. W., aged thirty-eight years. Advanced phthisis. In- 
spiration — 8 millimetres, expiration 12 millimetres. 
5. Pvieumonia.—In pneumonia the inspiratory pressure is 
reduced, and when the inflammation is extensive the expira- 
tory also, but the latter remains always greater than the 
former. I have had no opportunity myself to test the respira- 
tory power in pneumonia, and therefore cite the following 
three cases published by Eicbhorst: 1 
Case 1.—Laboring-woman, aged fifty-nine years. Croup- 
ous pleuro-pneumonia of the left inferior lobe. Inspiratory 
power —25 millimetres; expiratory 36 millimetres. On the 
day before the crisis, inspiratory power —31 millimetres; ex- 
piratory 32 millimetres. Eleven days after the crisis, inspira- 
tory power —40 millimetres; expiratory 44 millimetres. 
Fifteen days after the crisis, inspiratory power —60 millime- 
tres ; expiratory, 63 millimetres. 
Case II.—Laborer, aged forty-three years. Croupous 
pleuro-pneumonia of the left lower lobe. Inspiratory power 
— 23 millimetres ; expiratory power 37 millimetres. Six 
days after the crisis, inspiratory power —50 millimetres; 
expiratory power 54 millimetres. 
1 Op. cit., p. 278. 30 
Case III.—Laborer, aged twenty-seven years. Croupous 
pleuro-pneumonia of the left lower lobe. Inspiratory power 
—22 millimetres ; expiratory power 24 millimetres. In the 
further course of the disease, inspiratory power —13 millime- 
tres ; expiratory power 14 millimetres. Day of the crisis, in- 
spiratory power —36 millimetres ; expiratory power 38 mil- 
limetres. Three days after the crisis, inspiratory power —43 
millimetres ; expiratory power 46 millimetres, 
6. Pleurisy.—Here, similar pneumatometrical conditions 
obtain as in pneumonia and pulmonary phthisis. Aside from 
the pain which tends to prevent deep inspiration, and there- 
fore may reduce to a minimum the inspiratory pressure and 
correspondingly also the expiratory, it is obvious that com- 
pressed or inflamed consolidated tissue, or effusion, or pleural 
adhesion, must considerably interfere with inspiration, even 
when there is no pain. In all cases of pleurisy the pneuma- 
tometer registers insufficiency of inspiration : in mild cases the 
expiration may appear nearly normal; in severe cases there is 
insufficiency of both expiration and inspiration, the positive 
pressure of the former almost always exceeding, however, the 
negative pressure of the latter. As an example, I may men- 
tion, from my own observation, the case of M. R., aged thirty- 
nine years. Has had pleurisy repeatedly in his life, “caught 
a bad cold a few days ago;” dullness over middle and lower 
portions of left lung, with feeble respiratory murmur and fric- 
tion-sounds. Inspiration —26 millimetres, expiration 34 mil- 
limetres. 
Eiclihorst reports, in the case of a laborer forty years old, 
with pleurisy of the lower portion of the right side, exactly 
the same figures, while he found three weeks later the inspira- 
tory power to be —44 millimetres, the expiratory 50 millime- 
tres. 
Eichhorst also reports an interesting case of empyema in a 
boy fifteen years old, in which, after being twice punctured, 
the pleural cavity was opened with free incision, and cleansed 
daily by injection. Three months after the incision, inspira- 
tion measured —24 millimetres, expiration 29 millimetres. 
In the course of recovery these figures increased, and in six 
weeks became about normal, thus— 31 
April 12, 1872.—Inspiration —24 millimetres, expiration 
29 millimetres. 
Uiih.—Inspiration —35 millimetres, expiration 45 millime- 
tres. 
20ith.—Inspiration —37 millimetres, expiration 43 millime- 
tres. 
25th.—Inspiration —42 millimetres, expiration 78 millime 
tres. 
May 22cl.—Inspiration —60 millimetres, expiration 84 
millimetres. 
7. Narrowing of the Upper Air-Passages.—The largest 
number of pneumatometrical observations which I have made 
concern cases of laryngeal, tracheal, and pharyngo-nasal dis- 
ease. I shall not here specify the individual affections, but 
will merely remark that whenever swelling of the mucous 
membrane, neoplasm, obstructive accumulation of phlegm, 
presence of foreign body, paralysis of the vocal bands, or con- 
striction or compression from the outside, interferes with the 
normal admission of air, the pneumatometer immediately in 
dicates the inspiratory insufficiency: the expiratory pressure 
may be normal, or even increased, or else diminished, accord- 
ing to the circumstances of the case. I shall relate no cases 
in this connection, for I would hardly know where to begin 
and still less where to stop.—In pharyngo-nasal catarrh, the 
difference of the pneumatometrical figures obtained by breath- 
ing through my nose-piece and the mask (breathing through 
the open mouth) is a significant measure of the insufficiency 
of per-nasal inspiratory power. 
II. Diseases of the Circulatory Organs.—In fatty degenera- 
tion of the heart both inspiration and expiration are consider- 
ably reduced ; in hypertrophy and dilatation, especially inspi- 
ration is. In mitral disease and stenosis of the left auriculo- 
ventricular orifice, there is mainly insufficiency of expiration, 
while in disease of the aortic valves there is insufficiency of 
both expiration and inspiration, but particularly of the latter, 
as in the following case : II. C., aged forty-two years. Aortic 
obstruction and regurgitation ; commencing mitral regurgi- 
tation ; hypertrophy of the left ventricle. Inspiration —60 
millimetres, expiration 80 millimetres. 32 
III. Abdominal Affections.—All painful processes in the 
abdomen interfere with the power of respiration, especially 
that of expiration. Pregnancy, abdominal tumors, exuda- 
tions, and adhesions, cause expiratory insufficiency ; even if 
the inspiration he also reduced, it nevertheless in these cases 
usually exceeds, instead of being less than, the expiration. 
1. Of pregnancy, Eichhorst has reported fourteen cases 1 
of which I will cite the following three. All these women 
were, of course, free from disease of the chest: 
Case I.—Servant-girl, twenty-eight years old, primipara, 
in the last month of pregnancy. Inspiration —65 millimetres, 
expiration 48 millimetres. 
Case II.—Laboring-worn an, thirty-nine years old, eight 
children previously, six months pregnant. Inspiration —6l 
millimetres, expiration 21 millimetres. 
Case III.—Laboring-woman, twenty-six years old, one 
child previously, seven months pregnant. Inspiration —36 
millimetres, expiration 11 millimetres. 
2. Of tumor, I will cite two cases from Eichhorst, and a 
third from Waldenburg.2 
Case I.—Widow, sixty-eight years old ; very painful can- 
cer of the liver occupying the greater part of the right side 
of the abdomen. Inspiration —26 millimetres, expiration 18 
millimetres. 
Case II.—Shoemaker, thirty years old. Cirrhosis of the 
liver in the first stage, with enlarged spleen. Intense icterus, 
at present no ascites. Inspiration —72 millimetres, expiration 
40 millimetres. 
Case III.—PL, machinist, fifty-seven years old, Carcino- 
ma of the liver, principally left lobe, inspiration —120 milli- 
metres, expiration 52 millimetres. 
3. Of exudation, the following two cases are reported by 
Eichhorst: 
Case I.—Laboring-woman, thirty-three years old, Pain- 
ful peritonitic exudation in the left superior inguinal region, of 
traumatic origin. Inspiration —46 millimetres, expiration 17 
1 Op. cit., p. 279. 
2 “Die pneumatische Behandlung,” etc., op. cit., p. 78. 33 
millimetres. Thirteen days later, inspiration — 23 millimetres, 
expiration IT millimetres. 
Case II.—Servant-girl, eighteen years old. Very painful 
extensive parametritic exudation. 
April 28, 1872.—Inspiration —46 millimetres, expiration 
IT millimetres. 
May 5, 18T2.—Inspiration — 4T millimetres, expiration 20 
millimetres. 
23d.—Inspiration —29 millimetres, expiration IT milli- 
metres. 
27^A.—Inspiration —47 millimetres, expiration 34 milli- 
metres. 
4. Hutchinson claims that he has “frequently detected 
hernia ” by his instrument for measuring the respiratory 
power. The case in point which he mentions is as follows: 
Age, forty years ; weight, ten stone four pounds ; height, 
five feet six inches ; pulse, while sitting, 86 ; number of respi- 
rations per minute, sitting, 16 ; circumference of chest, 34-| 
inches ; mobility, 3 inches ; vital capacity, 222 cubic inches ; 
power of inspiration, 0.50 in. = about 13 millimetres; power 
of expiration, 1.00 in. 25 millimetres.1 
IV. Muscular Atrophy and Paralysis.—“ Atrophy of all the 
muscles of the body, of course, reduces the power of both 
inspiration and expiration. Atrophy limited to certain groups 
of muscles will influence that phase of respiration in which 
the atrophied muscles act. In progressive muscular atrophy, 
the inspiration will be principally affected, as usually the 
atrophy mainly concerns the muscles of the chest. If the 
atrophy extends to muscles concerned in expiration, this too 
will be influenced, till at length respiratory insufficiency be- 
comes so great that life can no longer be sustained. 
“ An effect similar to that caused by atrophy of the muscles 
must be produced by paralysis within the range of the respira- 
tory muscles. I had an opportunity to observe, and examine 
with the pneumatometer, a striking case of bulbar paralysis 
{glosso-palato-labial paralysis) complicated with progressive 
atrophy of the muscles of the trunk and upper extremities. 
1 Op. eit., p. 245. 34 
Miss L., twenty-two years old, has had for about a year a 
gradually-increasing nasal speech, afterward growing more 
and more peculiar and unintelligible. The patient cannot 
entirely close the lips so as to whistle, blow out a light, etc. 
Expectoration also difficult. When she swallows, the food 
returns through the nose. Respiration becomes increasingly 
difficult; the trunk and upper extremities very weak ; the pa- 
tient cannot hold up the head. The velum-palati is completely 
paralyzed (the vocal bands act normally) ; the tongue is atro- 
phied, trembles continually, and does not obey the will; the 
cavity of the mouth and pharynx is covered with viscous saliva, 
the mucous membrane reddened. Pectoral muscles very much 
wasted, the left more than the right; fibrillar spasms. The 
trapezius and muscles of the trunk also emaciated, on the right 
side more than on the left. Both arms partially atrophied. 
The lower extremities appear normal.” (Death ensued about 
six weeks later from insufficient respiration.) Maximum 
power of inspiration —20 millimetres, of expiration 20 milli- 
metres. 
“ When I made the patient perform suction through the 
mouth-piece of the pneumatometer, instead of inspiration, she 
could with difficulty raise the mercury to 60 millimetres. But 
it must be stated that she could not close her lips so tightly 
around the mouth-piece as to exclude the air.” 1 
Y. Rupture of the Membrana Tympani.—As a Curiosuvi 
I will mention that Hutchinson has recorded the following 
case of rupture of the tympanic membrane : Age, twenty-nine 
years; weight, ten stone one pound; height, five feet seven 
inches; pulse, sitting, 64; number of respirations per minute, 
sitting, 21; circumference of chest, thirty-four inches; mo- 
bility, three and a quarter inches ; vital capacity, two hundred 
and sixty cubic inches; power of inspiration, 0.50 in. — 13 
millimetres ; power of expiration, 1.30 in. — 33 millimetres. 
When this man closed his ears, his respiratory power was 
manifested as nearly three times as strong.2 
Yl. Phosphorus-Poisoning and some other Morbid Conditions. 
I Waldenburg, “ Die pneumatisehe Behandlung,” etc., op. cit., p. 79. 
II Op. cit., p. 245. 35 
—With a view of learning what influence different diseases 
might have upon the elasticity of the lungs, Peris1 experi- 
mented upon one hundred dead bodies by bringing the trachea 
into air-tight connection with a manometer, and measuring 
the pressure the lungs exerted by their contraction on opening 
the thorax. From similar experiments previously made by 
Donders, as well as his own, Peris estimated the elasticity of 
healthy lungs after expiration, i. e., from the cadaveric position 
of the thorax to complete collapse, to be the same as what Don- 
ders had concluded, viz., about 80 millimetres. In the body 
of a person who had died from diphtheritic cystitis, he found 
the pulmonary elasticity, tested in this way, very much reduced, 
although there was no disease of the lungs or pleura. He 
found the same thing in other cases with healthy lungs and 
pleura; thus, in a person dead from poisoning by phosphorus, 
the elastic pressure amounted to only 11 mm.; of five cases 
of ileo-typhus, it was in one as low as 5 mm., in two 12 mm., 
in one 25 mm., and in the other 36 mm. It would be very 
interesting if the investigations which these experiments sug- 
gest, would be followed up in living patients by means of the 
pneumatometer. 
Conclusion.—“With pneumatometry, the case is the same 
as it is with the other methods of examination, especially per- 
cussion and auscultation; it does not directly point out the 
presence of a particular disease, but it reveals certain abnormal 
conditions which may be caused by various, accurately recog- 
nizable diseases, between which differential diagnosis has to 
decide.”2 By means of the pneumatometer, dyspnoea, diffi- 
culty of breathing, which could hitherto be denoted by indefi- 
nite expressions only, can be characterized with exactitude 
both qualitatively and quantitatively—the first by showing 
whether it is inspiratory or expiratory, or both combined, the 
latter by determining in figures its precise extent or degree. 
And not only can the difficulty of breathing be determined 
when it exists subjectively as well as objectively, but in the 
first beginnings of a respiratory insufficiency, before the 
1 “Ueber die Druckverhiiltnisse im Thorax bei verschiedenen Krank- 
heiten,” “Deutsches Archiv fur klinische Medicin,” Bd. vi., 1869, p. 1. 
2 Waldenbnrg, “Die pneumatische Behandlung,” etc., p. 63. 36 
patient, himself is conscious of it, except perhaps upon very 
unusual exertion, before we can discover its existence by any 
other method of examination hitherto known, the pneuma- 
tcmeter may indicate a deviation from healthy respiration. 
Again, in obscure cases of differential diagnosis, the weight of 
the evidence supplied by the pneumatometer may turn the 
scale in the right direction, when this might not be discernible 
without its revelation. The importance and value of pneu- 
matometry can, therefore, not be doubted, and, without allow- 
ing it to take the place of other means of diagnosis, to it 
should unhesitatingly be awarded a prominent place along- 
side of the recognized and not-to-be-omitted methods of physi- 
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