Floating Minute Organic Matter in the Air 
AND ITS MANAGEMENT TO PREVENT 
Disease and to Mitigate or Control it, with a new 
DEVICE FOR 
ATMOSPHERIC PURIFICATION. 
: WITH /UNORIGINAL ILLUSTRATION.: 
By David Prince, M. D., of Jacksonville, Illinois. 
As to the number of microbes in the air, some reliable infor- 
mation is to be obtained from some recent observations by M. 
Miguel in a publication reviewed by M. Hacbe in the Revue <1e 
Chirurgie lor May and June, 1884. 
By these observations, what was known before in relation 
to the influence of the weather is further confirmed. 
The spores of the mould and cryptogams are especially vari- 
able, being most prevalent in damp weather. On the other hand, 
the septic microbes are least abundant during the rainy periods 
and most abundant during the periods of drouth. 
The average number of microbes found in the air at M’t 
Souris ( near Paris) was 84 to the cubic metre of air. In ap- 
proaching the centre of the city, the number was found to in- 
crease, being ten times that outside of the city. 
A series of observations was made at the top of the Pantheon, 
250 feet high, which showed that the air was more pure there 
than at M’t Souris, and ten times less charged with microbes 
than that on the surface in the centre of the city. 
In the interior of the well-kept habitations, the microbes in- 
crease during cold weather at the same time that they diminish 
in the free atmosphere. 
To give an example of the enormous accumulation in appar- 
ently well-kept houses in populous centres, observations were 
made in tho fourth story of a house recently built, in a bed- 
Reprinted from the St. Louis Medical and Surgical Journal, February, 1885. 2 
room occupied only twelve hours of the twenty-four, and there 
was found to be the large number of 526 microbes to the cubic 
metre of air, while in a room similarly situated at M’t Souris 
there were only 325. 
In hospitals, microbes have been found by M. Miguel to the 
number of 6,300 to the cubic metre. At the Hotel Dieu, 5,123 
in the summer and at the Hopital de la Pitie an average, by 
the year, of 11,100. 
The microbes found in surgical wards abound especially in 
the form of micrococcus. The microbes cultivated and inoculated 
into animals generally proved harmless, but in some rabbits and 
guinea pigs, grave affections were produced. 
The dust deposited upon objects was found to contain mi- 
crobes to the number of 750,000 to 1,300,000 to the cubic metre. 
The question is discussed by the author and his reviewer, 
whether the different forms of microbes are originally of differ- 
ent species and varieties, or whether they are capable of develop- 
ing or degenerating from one form and character into another. 
M. Miguel, M. Cohn and M. Noegali are quoted as having 
investigated the subject, the latter of whom is quoted thus: 
‘‘I am well convinced that too many species have been dis- 
tinguished among the schismocetes. It seems to me, on the 
other hand, somewhat probable that all the schismocetes consti- 
tute one natural species. There may exist among them a small 
number of genera or species now recognized of which each 
passes through a cycle of forms. ” 
M. Hache goes on to say, that successive cultures can pro- 
foundly modify the mode of their physiological activity. 
Examples are quoted of the metamorphosis of the compara- 
tively innocent hay bacillus (or bacillus subtilis) into the microbe 
of anthrax or splenic fever, which is one of the most virulent of 
the pathogenic forms. 
Finally, the cultivations of Pasteur are referred to as a proof 
of this position. On the other hand, Klein, in a series of articles 
in recent numbers of the Practitioner, which have been published 
also by McMillan in book form, claims that in those cultures in 
which septic microbes seem to have been converted into pathoge- 
nic microbes, and vice versa, there has not been sufficient care to 
secure purity of culture; that the kinds have become mixed to 
such an extent as to destroy the value of the observations. 
Many carefully made observations and somo diagrams are 3 
presented in the article by M. Miguel to show that, in the main, 
the amount of disease prevailing among people is proportionate 
to the number of minute organisms floating in the air; the 
greater amount of mortality in the centre of large cities corres- 
ponding with the greater number of floating microbes. 
One reason for this may be that cities furnish in decaying 
organic substances, the culture media, for the propagation of 
the dangerous forms of microbes, while in the country the decay- 
ing material is chiefly vegetable and fitted for the development 
of the zymotic and septic varieties, and equally unfitted for the 
development of those microbes which are known to produce 
specific diseases, the most common of which is erysipelas. 
According to present knowledge, the organic objects floating 
in the air may be classified as: 
1. The spores of objects many of which are to be seen with 
low powers. These became familiar to the earliest observers 
with the microscope, as the yeast plant.—Zymotic Agents. 
2. The spores and sometimes the developed forms of a class 
requiring higher and sometimes the highest powers to see them, 
which produce in nitrogenized organic material the phenomena 
of putrefaction but have no power of attacking living tissue. As, 
bacterium termo, hay bacillus—Septic Agents. 
3. The spores and sometimes the developed objects of a class 
generally requiring high powers for their observation, which pro- 
duce, when introduced into living tissues, or their fluids, changes 
characterized by the phenomena of special disorders, as erysipe- 
las, hospital gangrene, anthrax, tuberculosis, etc.—Pathogenic 
Microbes. 
In the following named diseases, this contagium has been 
proved to be particulate and vital, capable of mutiplying and 
perpetuating its kind when temperature and sustenance render 
it possible. 
These are, various septic developments, and erysipelas, hos- 
pital gangrene, small-pox, diphtheria, gonorrhoea, Koch’s septi- 
caemia of mice, Davaine’s septicaemia, chicken cholera, swine 
cholera, leprosy, Koch’s malignant oedema, anthrax, actinomy- 
cosis, tuberculosis, relapsing fever and Asiatic cholera. The 
last lacks the proof of successful inoculations after a series of 
cultivations. 
From this it is probable that all other contagious and in fee- 4 
tious diseases are originated and repeated by the action of simi- 
lar particulate vital agencies. 
DIGESTION. 
Dr. G. V. Black, in his book on “The Development of Poi- 
sons through Micro-Organisms ” has helped to generalize the 
conception of the manner in which living things appropriate nu- 
triment from surrounding food material. The amoeba converts a 
portion of its exterior into a temporary stomach by investing 
an object sufficiently small and digesting it, so that the nutritive 
elements of it may be absorbed. In accordance with the same 
idea, an object smaller than a blood cell comes in contact with 
the tissues of the body. If the vital condition of the tissue is 
sufficiently strong, the minute object may be digested. If, on the 
other hand, the vital force is weak, the cell, with which the 
invader comes in contact, is digested and the invader by natural 
increase becomes a spreading colon}', appropriating more and 
more of the adjacent substance. If several individual invaders 
gain entrance at ttie same time, the conquest is more rapid. It 
appears from the researches of Pasteur, Koch and others, that 
different microbes have different degrees of power in the attack. 
The septic micrococci, bacteria, and bacilli being only capable of 
attacking material destitute of present vitality, while they are in- 
capable of invading living substance. 
There are minute living objects, most commonly floating in 
the air, of many species or varieties and capable of living upon 
albuminoid material. In accordance with this idea, a blood clot 
exposed to the air and left in the wound may become the seat of 
septic changes, while the lips of the same wound brought together 
without any intermediate clot, though exposed to the same germ- 
hearing atmospheric contact, may digest the invading organ- 
isms and heal by the fir at intention. The blood clot, however, 
having no such vital power of resistance, may go into a state of 
putrefaction and become a source of irritation and infection to 
the adjacent living surface. Again, if the supposed blood clot is 
secluded from air containing organisms, or if the vitality of these 
invaders is neutralized by some antiseptic agent, as carbolic acid 
or mercuric bichloride, the clot fails to go into putrefaction and 
becomes penetrated by a living projecting growth, secreting a 
soluble ferment, by which the clot is digested and brought into a 
condition of solution to he absorbed and carried away. In this 5 
view, the question of the innocence of a blood clot turns upon 
the fact of its exposure to the atmospheric organisms in a condi- 
tion in which they can appropriate its nutritive material and 
thrive upon it. If, in a peritoneal cavity, a clot has had such an 
exposure it will probably go into a condition of putrefaction. Il, 
on tho other hand, through the absence of organisms brought by 
the air, or through their neutralization by antiseptic agents, the 
seeds of putrefaction are absent or inactive, the clot will become 
ultimately permeated by leucocytes, digested and absorbed. 
The same thing happens with catgut ligatures, with sponge, or 
other substance which the tissues have the power of dissolving 
by the production of an appropi’iate digestive fluid. Catgut may 
be said to be easy of digestion, so that it disappears in a few days. 
Silk is more difficult of digestion and is, therefore, more liable to 
result in an abscess for its ultimate expulsion. Linen is more 
difficult still of digestion and, therefore, more liable than silk to 
the formation of an abscess. Silver is again absolutely indiges- 
tible, while it is unirritating and may innocently remain any 
length of timo in contact with living tissue. 
A catgut ligature or a blood clot containing septic germs, is 
almost certain to proceed to putrefaction, unless from the small- 
ness of volume, the living tissues may be capable of surrounding 
tho germs and infiltrating the clot, catgut or other substance con- 
taining them, with a digesting agent capable of destroying tho 
vitality of the microbes j of dissolving and carrying away both 
them and their store of food. 
As these agents, either in their developed or in their germ 
state, float everywhere in the air without the possibility, by any 
means hitherto practiced, of completely excluding them, except 
on a very small scale, their entrance to some extent into every 
open wound is a matter of course. 
This consideration points to the importance of the employ- 
ment of local antiseptics during the progress of operations atten- 
ded by incisions and as long afterwards as the wound remains 
open. The antiseptics are employed in the form of spray or of 
a continuously flowing stream. 
The danger is greater when the invaders are not simply the 
agents of sepsis, but are the pathogenic microbes of erysipelas, 
hospital gangrene or other infectious disease. 
These are proved to have a capability of attacking living tis- 
sues and of nroducing by the employment of a stronger diges- 6 
tivo agent, the destruction and appropriation of live cells and 
fixed tissue, without any other natural limit than the whole extent 
of the body attacked. 
If tho invading agent be very small in amount and the vital 
condition of the patient be perfect, the invaders, if not repulsed 
or destroyed in the very entrance, may be limited to the forma- 
tion of an abscess, while, if the vitality of the patient be feeble, 
the smallest invasion may end in tho complete destruction of the 
system. This may be the reason why a dissecting wound pro- 
duces a minute abscess in one person, an abscess with a slight 
fever in a second, and a fatal blood-poisoning in a third. The 
difference lies in the power of resistance, and not in the nature of 
the invaders. 
Tho use of medicinal agents taken by the mouth or injected 
into the tissues and vessels has for its object the increase of the 
power of resistance, as when we combat erysipelas by the inter- 
nal employment of chloride of iron. 
The local applications, on the other hand, generally have for 
their object the destruction of the invading agents. 
The local agent applied in anticipation may, however, have a 
two-fold effect; first to destroy or render inactive the atmosphe- 
ric living agents, and next to preserve tho vitality of the incised 
or lacerated surfaces, so that the invaders may be destroyed by 
the defensive fluid secreted by the living surfaces. 
A stream of the aqueous solution of carbolic acid of the 
strength of 1 to 100, of mercuric bichloride of a strength of 1 
to 1,000, or 1 to 10,000 does not necessarily destroy the spores 
of septic and pathogenic microbes, but it destroys the present 
activity of those which are in a developed and active condition. 
It at the same time preserves the moisture and the unimpaired 
condition of the exposed surfaces, so that the invading germs are 
immediately surrounded by a secretion of a strong character 
which invests the invading germs and digests them. A stream 
of pure water would have the same effect upon the incised or 
lacerated surface, only to be sure of its freedom from organic life 
it must have been recently boiled for more then thirty miuufes. 
Klein in his little book recently published,* states that distilled 
water becomes in a few hours full of septic microbes in an active 
developed state, ready to multiply and flourish when introduced 
* Micro-organisms and Disease. McMillan. 1884. 7 
into any substance furnishing oxygen, nitrogon, and hydrogen, 
i. e. any natural animal or vegetable substance. 
There are numerous illustrations of the power of resistance 
of living tissues against organisms which are simply septic in 
their character. 
It is probabl}r rare that a hypodermic injection of any sub 
stance is made without introducing at the same time a bubble ol 
air containing a colony of micro-organisms, either as germs or in 
a developed condition; yet the formation of an abscess or a 
more severe general septic poisoning is an exceedingly rare oc- 
currence. These agents must be devoured as they are surrounded 
by a stronger vitality. 
The introduction of air on a very large scale occurs after 
wounds connecting the respiratory passages with the surround- 
ing connective tissue, and yet the air is generally absorbed with- 
out evil consequences. 
However, if instead of common air it be loaded with the 
floating products of erysipelas, puerperal or other septic fever 
or hospital gangrene, the hypodermic injection might introduce 
an enemy of greater destructive force, capable of appropriating 
and living upon the surrounding cells and fixed tissues, the vi- 
tality of which it overmasters. 
Again, if the patient is in a condition of very feeble vitality, 
the minute blood clot occasioned by the point of the needle may 
afford an insufficient resistance to the relatively superior vital 
force of the invading microbes, though only of the septic class. 
In view of these facts and reasons, the most important consi- 
deration in relation to surgical (or accidental) wounds is the 
purity of the atmosphere, or its freedom from microbes, especi- 
ally those of a pathogenic nature. The latter are very apt to be 
present in houses which have been contaminated by erysipelas 
and by those septic fevers which are attended by the presence of 
pus in a putrefactive condition, while the out-door air or the air 
of an apartment not used for dwelling purposes, is likely to have 
only those microbes which are capable of starting putrefaction 
in non-vital animal and vegetable substances. 
The second most important consideration is the health of the 
patient, or his power of resistance to the ordinary septic influ- 
ences which are almost everywhere present. 
The power of medicines to increase the resistance is not here 
paroper subject to consider; suffice it to say, that a great eonsid- 8 
oration is the neutralization of the latent malarial poison ready 
to develop on any occasion of depressed vitality. 
The management of diet is of equal importance, but not in 
the scope of consideration to be entertained here. The diet which 
for the time secures the best state of health, or the management 
which secures a demand for nutriment and a capability of diges- 
tion and assimilation, are expressive of the end to be secured. 
The third consideration is that of the local management of a 
wound—There are three things; (1.) to protect the surface from 
drying and the consequent tendency to die and become the seat 
of septic changes. This is done by a spray or by irrigation, or 
by the presence of a clot which should not needlessly be wiped 
off until the time for the final dressing. 
(2.) The presence, in the fluid of the spray or irrigation, of 
some agent which destroys or temporarily neutralizes the float- 
ing organic substances in the atmosphere. It is probable that 
the best agent yet tried for the purpose, is an aqueous solution 
of mercuric bichloride, and, as the result of experience, a strength 
of 1 to 10,000 for a prolonged contact. 
The agent can be applied without injury to the vitality of 
the exposed wound surfaces, and while too weak to destroy the 
vitality of the spores of pathogenic microbes, it is sufficiently 
strong to nullify their present activity and prevent the immediate 
production of their digestive soluble ferment. The substances to 
be applied to wounds to prevent subsequent septic development 
are boric acid and iodoform. The latter is capable of being intro- 
duced into a wound without interfering with union of the sur- 
faces by the first intention. 
The iodoform is ultimately disposed of along with the mate- 
rial of the coagulum which envelops it. The investment of the 
wound with borated cotton affords a material which retards or 
prevents putrefaction in the effusions and exudations escaping 
from the wounds by openings or through drainage tubes. 
The borated cotton receives these products and prevents their 
putrefaction, thus affording a material for a dry dressing which 
makes it practicable to subject a wound to dressings at infrequent 
times. The baking slowly of borated or sublimated cotton un- 
til it assumes a light brown color, is found to afford a dressing 
in which the exudations which have escaped from a wound and 
become dry do not putrefy. 
For a wet dressing, there is nothing yet known superior to a 9 
drip of carbolic acid of one per cent, strength, applied constantly 
or at times not more than 20 minutes apart, in order that the pres- 
ence of the agent may be perpetual. This is incapable of destroy- 
ing spores, but is yet strong enough to prevent the activity or 
vital manifestation of the septic microbes, and is probably capable 
of suppressing the vital manifestations of those of a pathogenic 
character, or those having the power of producing specific dis- 
eases, as those of erysipelas, hospital gangrene and other dis- 
eases, many of which have not yet been carefully studied, while 
yet the applications are weak enough not to injure the surfaces 
to which they are applied. 
It is not the purpose of this paper to go much into detail, but 
to indicate in a brief way, the advance of thought upon the sub- 
ject, based upon tho careful investigations which have proved 
beyond dispute the dependence of many diseased manifestations 
upon the presence of micro-organisms. 
The conception of digestion, as the means by which micro- 
organisms are enabled to attack and live upon substances that 
go into decomposition in connection with their growth and mul- 
tiplication, is further developed by Dr. Black in his book,* pp 
50 & 85. 
Quoting from Lister,f he states that this observer found that a 
few germs, of the species of bacterium found in the hydrant water 
of London, contained in a single drop of water, could not start 
decomposition, but a larger amount could. At the same time, the 
smallest amount of putrid material would start decomposition. 
The explanation approached by Lister and clearly stated by Dr. 
Black, is that in the detached state, a bacterium is not able to 
develop a ferment in sufficient amount or intensity to overcome 
the chemical union of the serum, but when introduced in sufficient 
number to unite their digestive products, or in a condition in 
which the individual organisms are already surrounded by their 
ferment, they are able to attack the serum, living upon it and 
multiplying in it. 
This consideration has an important surgical relation. In this 
view, it is not necessary that an agent acting as an antiseptic 
should be capable of destroying the micro-organism. If it is 
capable of neutralizing the digestive ferment produced by the 
* Formation of Poisons by Micro-Organisms. Preslev Blakiston, 
8ion & Co., 1884. 
f Transactions of the International Medical Congress, Lon Ion, 1881. 10 
attacking micro-organism, the development and multiplication of 
the microbe may be held in check until destroyed by the diges- 
tive action of the cells of the surface of the wound invaded. 
The fact that spores will live in alcohol, and afterward thrive 
when planted in a good field, does not militate against tho uselul- 
ness of alcohol as an antiseptic, however poor a disinfectant it 
may be. By way of reference to the alphabot of tho subject, tho 
facts known of the nature of the poisons evolved by micro-or- 
ganisms imply that by their nature and their modes of action 
they may be arranged in three classes. 
1. The local effects of a digestive fluid by which the cells 
attacked are paralyzed and then destroyed. When the invad- 
ing organisms are circulating in the blood, they infiitrato tho 
white blood corpuscles and destroy them. A period of incuba- 
tion elapses between the invasion and a sufficient multiplication 
of the microbes to produce a manifest local disease or to affect 
the general health. 
The superior vital force of the blood or tissues may arrest or 
destroy the invading agents. When unable to do this, the forces of 
resistance may yet establish a wall of limitation so that thero may 
be only a local inflammation or a small abscess; and when tho 
localization is less complete, the lymphatics going from the spot 
affected may become inflamed. 
2. The production of a poisonous waste product, which, being 
taken up into the circulation, poisons in analogy with morphia 
and Btrychnia, which alkaloids in this view, may bo classed as 
alkaloid waste products of the poppy and the strychnos. 
The inoculation of such a poisonous waste product produces 
immediate disease without an intervening period of incubation. 
Sepsin, the waste product of septic action, when filtered out 
from the microbes which produce it, produces gen- 
eral disease when inoculated, though there is nothing living in it 
by which it can be multiplied or reproduced by the processes of 
cultivation. This impossibility of cultivation shows that the poi- 
son has been separated from the vital agents which have pro- 
duced it. 
The entrance of sepsin in sufficient quantity, whether gener- 
ated in a wound or ulcer, or injected artificially, destroys life, but 
if insufficient for this, recovery takes place as in the case of other 
poisons. 
3. Pathogenic poisons are those of special diseases which are 11 
supposed to arise from microbes of peculiar species on one theory, 
or on another theory, such rs are profoundly modified by the 
temperature and the food-media with which their growth and 
multiplication have been circumstanced. 
These microbes are called by Klein pathogenic to distinguish 
them from microbes which produce only Septic effects and which 
are called septic microbes. All these pathogenic microbes have 
a period of incubation, some longer and some shorter. 
During this period of incubation, the invaders are living upon 
the tissues at the point of entrance, multiplying and extending, 
or if floating in the blood, they are attacking the white blood 
corpuscles in greater and greater number. According to their 
nature they produce different diseases. 
Some cause a gangrene as they travel and are very local, until 
the system becomes attacked by septic poisoning from the septic 
decomposition of whatever is destroyed, while others diffuse 
themselves in the blood. Others, like the bacillus of tuberculosis 
and of actinomycosis, lodge upon particular spots, multiplying 
and destroying the tissues. 
The mode of poisoning by atmospheric micro-organisms which 
is most to be feared in surgery, is that of erysipelas, because the 
agents of this infection are more abundant in dwelling houses 
and hospitals and most difficult to eradicate. The micrococcus 
of erysipelas is extremely minute. 
As quoted by Klein (p. of Micro-Organisms) Feheleisen cul- 
tivated the micrococcus of erysipelas through fourteen genera- 
tions, and with the last generation produced erysipelas on the 
ears of rabbits, and on some tumors and lupus ulcers of human 
patients, the application being made for the purpose of curing the 
local diseases. 
Feheleisen found that at! weeper cent, solution of carbolic acid 
and a cent, solution of mercuric bichloride destroyed the 
vitality of this micrococcus. 
It thus appears why a spray or irrigation of either of these 
agents upon a wound during the progress of its formation in 
the course of a surgical operation, is a protection against an ery- 
sipelatous contamination. 
The treatment of microbes in order to destroy them or render 
them inactive is (1) by heat not less than 150° F. (71° C), and 
some of them require 300° F. (148° C), prolonged and repeated ; 
(2) by disinfectants which destroy the germs of the dangerous 12 
microbes, and by antiseptics which hold their development and 
activity in check without destroying them. An interesting illus 
tration of this distinction is given by Dr. W. J. Miller, of Dundee, 
Scotland, in an article on contagium in the London Practitioner 
for Sept., 1884. 
Dr. Dougal suspended the action of vaccine lymph by the 
incorporation of carbolic acid, but when, by exposure to the open 
air, the antiseptic had evaporated the lymph was found to have 
been preserved unimpaired. According to this and some other 
observations “ Carbolic acid is not a disinfectant, not a destroyer 
of organic matter, but rather an antiseptic or preserver of organic 
matter, arresting and preventing putrescent and fermentive 
change, and suspending zymotic action for a time, leaving such 
matter unchanged after the volatilization of the antiseptic.’’ 
This distinction may be criticised, by saying that a strength 
of carbolic acid of sufficient intensity to hold back and paralyze 
the invaders, may be weak enough not to injure the organisms 
to be preserved. In the case of vaccine virus, it is not injured 
by a strength of 2} per cent, though the putrefactive microbes arc 
held in check. These microbes would quickly destroy the spec- 
ial contagium if not opposed by this or some other antiseptic. A 
stronger preparation of carbolic acid would destroy both inva- 
ders and defenders and be a disinfectant. A strength of i per 
cent, preserves bread pulp and J per cent, preserves broth and milk. 
Washing the hands in a 5 per cent, solution is thought to be the 
weakest solution capable of protecting the hands against receiv- 
ing and imparting contagium, and this is far inferior to a solution 
of sulphurous acid. In the form of vapor, however, it is doubt- 
ful whether carbolic acid has any effect whatever on account of 
its great dilution. 
All the experiments which have been made with carbolic acid 
vapor are negative. 
Among the disinfectants, Dr. Miller (above quoted) considers 
sulphurous acid (from burning sulphur) the most valuable of all. 
Its vapor destroys every microbe, whether zymotic, septic or 
pathogenic. 
Its gas permeates every crack in the walls of a room, and its 
solution is easily applicable to the surfaces of solid bodies. Its 
only objectionable feature is the difficulty of employing it in 
rooms while people are in them. 
It is not necessary here to enumerate and compare even the 13 
principal antiseptics and disinfectants. Chlorine, hydro-chloric 
acid, iodine and bromine are powerful but difficult to manage. 
Salicylic acid, boric acid, iodoform and mercuric oxides and 
salts are excellent antiseptics for local application in the solid 
form, the choice among them being determined by circum- 
stance and convenience. 
AIR PURIFICATION. 
Wo como now to another method of managing the subject. 
Taking a hint from the observations recently made in Paris, and 
quoted in the beginning of this paper upon the effect of rainy 
weather upon the number of microbes floating in the atmosphere, 
it occurs to ask, whether or not it is practicable to subject the 
air entering an operating room to the influence of artificial 
showers in order to precipitate to the ground the whole or the 
greater part of these enemies of surgery. 
They are known to be heavier than the air because they en- 
tirely disappear from the air within a tight box which has been 
for several months in one position. This principle of rest is of 
no use to us, for the purification of the air of an operating room 
by this means is impracticable. 
The dry filtration by means of cotton or other substances to 
entangle and arrest the particulate substances floating in the air, is 
not practicable on account of the rapidity necessary in the entrance 
and exit of the air in order to displace the agents entering from 
without during the progress of an operation, and those emanating 
from the occupants of the room. If, however, we can cause the 
air entering the room to pass though several showers of water, 
we have an expedient which may entangle these objects and carry 
them to the ground. 
The following is a description of such a device. 
1. Basement.—On the right hand is an entrance ventilator, twenty- 
inches in diameter, in which a steam jet is made to play in order to infil- 
trate the entering air witli very tine globules of water. (2) (3) 
2. The air thus moistened passes in the direction of the arrows under 
a curtain or diaphragm reaching within fifteen inches of the floor. Under 
this curtain lies an iron pipe with numerous small holes drilled in the 
upper side.furnishing an interrupted spray under the curtain, and making 
it necessary for all the moving air to pass through this artificial shower 
near to the floor and into the next room warmed by the stove seen on 
the left hand of the diaphragm or screen. (5) 
3. The air, thus warmed, passes through a filter, composed of shelves 
of thin muslin through which water is dripping. The warmed air 14 
first passes over the top of a vertical screen to avoid the entrance of 
cold air, then under another vertical screen, and then hack and forth 
between horizontal screens fifteen inches apart, dripping with water and 
finally through the spray which supplies this water. (C>) 
Thus there are three liltrations of the air, one by steam and two by 
water. 
4. The air thus filtered three times, emerges through an opening in 
the floor and goes to the top of the operating room above. [7] 
Fig. 1. 
5. Operating Room.—The exit ventilation is seen on the 
opposite, or right hand side of the room, in the direction of the 
gurrows.) This is effected by a movablo shaft or box, made by 
Basement below and Operating Boom above—Scale, o?ie to sixty. 15 
tacking muslin upon a frame, so that it can be set up against a 
window, with the upper sash pulled down to the necessary degree. 
The shaft can bo shifted from one window to another to be free 
from the pressure of the wind, or on the opposite side, or from 
the wind. The arrangement thus far, is to get an atmosphere 
more pure than that outside, and through the frequent change of 
the air in the operating room, to get rid, to the greatest possible 
degree, of the contamination of the air (during the progress of 
an operation) by the emanations from surgeons, assistants, spec- 
tators, and the patient himself. This change is secured by the- 
entrance offiltered air from the basement and the exit, from the 
floor of the operating room, of the air which has been the longest 
in the room, having descended gradually from the ceiling where 
the air is hottest, after having entered from the warming cham- 
ber below. 
6. The floor of the operating room is made of yellow pine, 
and filled with paraffin to as great a depth as heated smoothing 
irons can drive it. By this means, all cracks are filled so as to 
be non-absorbing. Under this, lies a layer of tarred paper upon 
a common floor upon the joists. Between the joists, lies a layer 
of tarred paper upon the ceiling, the underside of which ceiling 
is painted, and lined with muslin while the paint is fresh. The 
muslin is again painted on the under side. The floor thus has 
seven layers, including the joists. 
7. The operating room is free from closets where anything 
unclean can be hidden, and all wood work is either paraffined or 
painted. 
8. There is no opening into any other room; about six feet 
of space intervening between the door of entrance and the near- 
est wall of the main building. 
9. Before the use of the room for an operation involving 
the opening of a joint or the peritoneal cavity, it is intended that 
the rooms above and below shall be fumigated by sulphur burn- 
ing in the basement. An iron pan for this purpose is figured in 
the cut(8) resting over a Bunsen burner for the combustion of 
sulphur. This is to be done for the destruction of any floating 
material of an organic character which may have gained en- 
trance while the room may have been out of use. 
It is found by trial that when the different sprays of water 
are going, one can remain very comfortably in the room above 
while sulphur is burning in the room below ; the fumes being first 16 
absorbed by the steam and having then to pass through the two 
different showers of water become thoroughly percipitated. 
10. This building is the execution of a theory of combining 
the best known expedients for securing the best possible atmos- 
phere for surgical operations, by excluding noxious agents and 
by destroying or expelling those which may have stolen in, or 
which may be introduced by the patients, or by the surgeon and 
his assistants and guests. It is supposed that enough air will 
enter and escape to change the whole volume of the air once in 
fifteen minutes. The exit draft coming from the floor will carry 
away most of the floating material. 
11. The employment of a spray or douche of carbolic acid 
of the strength of 4 to 100, or of mercuric bichloride of 1 to 10, 
000, or other antiseptics, locally applied, though less necessary 
than in an ordinary room, may yet be resorted to in order not 
to omit any useful precaution. 
12. The employment of solutions of carbolic acid, mercuric 
bichloride or permanganate of potash with the nail brush for 
cleaning the hands should be supplemental to the fixed provi- 
sions against septic and pathogenic particulate infection. 
13. The bathing of the instruments incarbolized water, while 
this proceeding is incapable of disinfecting or destroying any 
germs which may adhere to them, may yet be useful in an antisep- 
tic sense i. e. by destroying microbes in a developed state or free- 
ing them from the supposed secretion by which they may bo sur- 
rounded, and which may serve as their weapon of attack by 
which they digest or destroy the surfaces with which they come 
directly in contact. 
14. A useful precaution on the part of the operator may be 
a bath and a change of clothing, the hair and head being dam- 
pened so that dust will not escape from them ; and yet another 
precaution may be the wearing of gowns which will oblige all 
dust escaping from the clothing of the operator and his assistants 
to fall to the floor whence it may escape with the draft which 
carries out the lowest stratum of the air. 
Note. The construction of an operating room on the principles 
here explained in a Hospital already built, without erecting a detached 
building, would require that two rooms should be taken one above the 
other and if the upper one can have a skylight it will be of great advan- 
tage. The lower room might be in the basement with a shaft not less 
than (3) three feet in diameter extending to the upper room which might 
be under the roof for the advantage of a skylight. All communications 
must be closed by brick and mortar and an entrance opening made in the 
outer wall, the approach being secured by means of a platform on the out- 
side of the building, so that it must be unavoidable to go into the open 
air for entrance and exit. The lower room should be enuallv shut off from 
communiation with other rooms of the building. GEA