PILOCARPINE: 
ITS PHYSIOLOGICAL ACTION AND THERAPEUTIC 
USES. 
WITH EXHIBITION OF SPECIMENS SHOWING CHANGE 
IN THE COLOR OF THE HAIR. 
Read before the New York Academy of Medicine by Invitation, 
April 3, 1893. 
BY 
D. W. PRENTISS, M.D, 
WASHINGTON, D. C. 
REPRINTED FROM THE THERAPEUTIC GAZETTE, OCTOBER 16,1893. 
DETROIT, MICH. : 
GEORGE S. DAVIS, PUBLISHER. 
1893. Pilocarpine: Its Physiological Action 
and Therapeutic Uses, with Exhibi- 
tion of Specimens showing 
Change in the Color 
of the Hair. 
THE drug which I have selected to bring 
to your attention this evening is the 
most important addition to the Pharmacopoeia 
of 1880, and is one that has interested me for 
several years past. 
In one particular its action is unique, and is 
confined, so far as I know, to my own experi- 
ence. I refer to the action of pilocarpine in 
changing the color of the hair. 
This action of the drug alone, however, is 
too limited for general interest, and the title of 
the paper is made to read "Pilocarpine: Its 
Physiological Action and Therapeutic Uses. 
With Exhibition of Specimens showing Change 
in the Color of the Hair." 
I am warned that this essay must not be too 
long, and therefore shall try to condense it as 
much as possible. 2 
Division of the Subject. 
1. Brief Statement of Natural History. 
2. Physiological Action. 
1. As a sudorific. 
2. As a stimulant to accommodation of 
eye and contraction of pupil, and 
as stimulant to the hearing appa- 
ratus. 
3. As a stimulant to the growth of the 
hair,-action in changing color 
of hair. 
j. Therapeutic Uses. 
1. Most important as a sweat pro- 
ducer. 
2. In diseases of the eye and ear. 
3. Use in promoting growth of the 
hair. 
1. Natural History. - (Pharmacographia), 
Pilocarptis pennatifolius, Lemaire. 
A shrub, growing to height of ten feet; 
native of the eastern provinces of Brazil. 
(For plate, see Bentley and Trimen, Part 
XXXII., 1878.) 
There are other species included under the 
general name of jaborandi, but the pennati- 
folius is the most active and the one recog- 
nized by the U. S. Pharmacopoeia. 
The principal constituents of the leaves are: * 
1. Pilocarpine, the active principle. 
2. Jaborine. 
3. An essential oil, which shows in the pel- 
lucid spots of the leaves and belongs to the 
terebene series. 
* Through the kindness of Merck & Co., of New 
York, specimens of the pure alkaloids and their salts 
were exhibited. 3 
Pilocarpine is an amorphous soft amber- 
colored mass, discovered in 1875 by Hardy, 
and makes crystallizable salts with acids. 
Leaves contain one-half of one per cent. 
Jaborine has the same chemical constituents, 
but differently arranged, and gives just the op- 
posite physiological action to pilocarpine. 
The action of jaborine is identical with atro- 
pine. 
Hence the importance that the pilocarpine 
be pure and free from admixture. This ad- 
mixture probably explains the different re- 
sults obtained by different investigators as to 
physiological action. 4 
The essential oil is inert. 
2. Physiological Action. 
i. As a sudorific. 
Perhaps the shortest and least tiresome 
method of describing its physiological action 
will be to mention an actual case,* and as 
this is the case in which the change in the 
color of the hair occurred, it will be the more 
appropriate. It also illustrates the use of the 
drug in uraemia. 
The patient, female, aged twenty-five years, 
was suffering from pyelo-nephritis with pro- 
longed anuria. For ten weeks the amount of 
urine did not average two ounces daily, and 
this contained offensive pus. At one time- 
from December 16 to 23, seven days-not a 
drop was passed, although the catheter was 
used twice daily. 
Again, from January 22 to February 2- 
eleven days-not a drop was excreted, the 
catheter still being introduced twice daily; 
and from January 22 to February 12-twenty- 
one days-a total of but little over two ounces 
in all were passed. Twenty-one days of almost 
total anuria. 
Previous to December 16 the hot bath 
and hot packing were several times resorted 
to to produce diaphoresis, without effect. 
Extreme uraemic symptoms had developed,- 
no itching, but incessant vomiting, nervous 
restlessness, twitchings of the muscles, flushed 
face, severe headache, confusion of vision, and 
delirium. 
An attempt was made to give infusion of 
jaborandi by the stomach, but it was re- 
* Philadelphia Medical Times, July 2, 1881. 5 
jected, as was also the solid extract in gelatin- 
coated pills. 
Finally, December 16, hydrochlorate of 
pilocarpine, i centigramme, was administered 
hypodermically, the patient being wrapped in 
a warm blanket, with bottles of hot water 
around her. 
On two or three occasions later, when the 
blanket and hot bottles were omitted, there 
was less sweating. 
From December 16 to February 22 twenty- 
two sweats were administered, requiring thirty- 
five or forty centigrammes of pilocarpine. As 
the patient became accustomed to the medi- 
cine, it was found necessary to increase the 
dose to two centigrammes. 
An analysis of the phenomena following the 
use of the drug in one of these "sweats," it 
seems to me, will be more graphic than a gen- 
eral description of the physiological action. If 
it is tiresome, I crave pardon. It shall, at least, 
be brief. 
A Pilocarpine Sweat, 1 Centigramme Hypo- 
dermically.-The action of the drug was care- 
fully noted. Immediately, almost before the 
needle was withdrawn, the face and neck 
would flush bright red, and dimness of vision 
be noticed ; then palpitation. In three min- 
utes, slight nausea; eyes, nose, and mouth be- 
ginning to water and skin showing moisture. 
In seven minutes, free vomiting, profuse sweat- 
ing, and salivation. 
Analysis of Separate Symptoms. 
Perspiration.-First noticed on forehead and 
neck, then the skin of the whole body, which 
had been previously dry and harsh, became 6 
moist. When sweating was fully established, 
the water ran in little streams over all parts of 
the body. In the face it was with difficulty 
kept out of the eyes. In five minutes the hair 
would be saturated, and though wiped as dry 
as possible, it would be again soaked in a few 
minutes. In odor the perspiration was offen- 
sive, and on several occasions had a distinctly 
urinous smell. 
Salivary Glands.-In the beginning of the 
ordeal water flowed freely from the eyes and 
nose, as well as from the mouth, but when 
salivation was fully established, the eyes and 
nose ceased to discharge. The saliva was vis- 
cid and tenacious, so that to clear the mouth 
it was necessary to use a handkerchief. Its 
flow was so profuse that, after thus clearing the 
mouth, she would not have time to get a drink 
to quench thirst before the mouth would again 
be filled. So, also, talking connectedly was 
prevented by the same cause. The water 
drank during a sweat at no time exceeded a 
gobletful. 
Vomiting.--The vomiting continued through- 
out, almost without intermission, and was the 
most distressing symptom of the ordeal. After 
a spell of vomiting, the patient would lay back 
on the pillow exhausted, hoping for a rest, but 
it would immediately return. The odor of the 
ejecta during February was very offensive, like 
decayed vegetable matter. 
The amount discharged in this way, which 
included saliva, was never less than two quarts, 
and often a gallon. The patient stated that 
she did not swallow the saliva, and insisted 
that the material vomited came from the 
stomach. This would indicate that pilocar- 7 
pine also causes a fluid discharge from the gas- 
tric mucous membrane. Nausea and vomiting 
ceased as soon as the effect of the medicine 
passed off. Food was then taken and retained, 
although previously the stomach rejected every- 
thing. 
Bowels.-Just as soon as perspiration was 
fully established the bowels moved,-always a 
large action, and sometimes more than once. 
This action on the bowels is twofold : (i) from 
an increased amount of liquid in the intestines 
and (2) from increase of peristaltic action. 
There were seldom more than two or three 
movements. 
Action on Heart.-Pulse became rapid in a 
few minutes, and when the action of the drug 
was fully established, a thumping palpitation 
added to the distress occasioned by the vomit- 
ing. This "thumping" could be heard at a 
distance of six feet, and continued with de- 
creasing violence until the close of the parox- 
ysm. The pulse ranged from 120 to 136, and 
was weak and compressible. 
Eyes.-Pupils contracted to a small point. 
Sight became impaired at the first rush of 
blood to the face, and the dimness continued 
until it was impossible to distinguish objects 
beyond the foot of the bed. 
As the effects wore off the exhaustion was 
extreme ; pulse 130 and feeble. But there was 
a grateful sense of relief, and a disposition to 
sleep even before the sweating ceased. The 
head was no longer dizzy, pain less, stomach 
free from nausea, and tongue free from coating. 
A quiet sleep followed, lasting several hours, 
from which the patient awakened refreshed 
and hungry. 8 
Amount of Fluid discharged during a Sweat. 
-Of course, this could only be estimated. 
The fluids from acts of vomiting were caught 
in a basin and emptied three or four times, 
and each time contained not less than a quart. 
The blanket in which the patient was wrapped 
was saturated, as was also a folded sheet under 
the blanket. The pillow was saturated and 
the bolster beneath wet. 
An experiment was made of saturating the 
blanket to as near as possible the same extent, 
and five pints of water were required. 
Putting these together, then, we have the 
following calculation : 
Pints. 
By vomiting and saliva 7 
By saturated blanket 5 
By sheet, pillow, and body-clothing 2 
14 
This seems almost incredible, but I believe 
the amount is strictly within the truth. The 
patient and her attendants thought the amount 
understated rather than exaggerated. 
It is unnecessary to record further the details 
of this case, as I have used it in illustration of 
the action of pilocarpine. 
Suffice it to say, the patient recovered, and is 
alive to-day. 
It only remains in this case to record the re- 
markable change in the color of the hair which 
took place under the influence of the pilo- 
carpine. 
All of the patient's life (she was twenty-five 
years old) up to the beginning of the treat- 
ment her hair was light blonde with a yellow 
tinge. Twelve days after beginning the injec- 9 
tions it was noticed to be darker, and from that 
time the change of color was rapid until, two 
months later, it was black.* 
The hair also became coarser and thicker in 
its growth. The eyebrows and eyelashes, be- 
fore almost invisible, came out beautifully pen- 
cilled. The hair on other portions of the body 
participated in the change. 
Modus Operandi of Pilocarpine. 
Upon sweat and salivary glands : 
1. Stimulates nerve-centres of these glands. 
2. Stimulates efferent nerves to the glands. 
3. Stimulates glandular structure itself to 
increase the secretion. 
In brief, pilocarpine is a specific diaphoretic 
and sialagogue by its elective action on these 
glands. 
It increases also the secretions from the 
mucous membranes of the 
Bronchial tubes, 
Stomach, 
Intestines and kidneys, 
But does not increase the flow of bile. 
As to the discharge from the bronchi, 
stomach, and intestines, it is difficult to say 
how much of the liquid is swallowed saliva. 
There is not time in this paper to go into de- 
tails of the experiments made to show the man- 
ner of the action of this drug, nor is it neces- 
sary, since they are fully discussed in the works 
of H. C. Wood, Lauder Brunton, Ringer, and 
others. 
Brunton speaks of the enormous secretion 
* Specimens were exhibited showing changes as above 
described. 10 
from the sweat-glands, and states that it 
amounts to from one to two pounds, and, to- 
gether with the salivary secretion, often as 
much as eight pounds. 
In the case which I have mentioned above I 
have estimated the amount, including the vom- 
iting, at fourteen pounds. 
I expect to have this statement challenged, 
and admit that it appears incredible that a girl 
weighing ninety or one hundred pounds could 
thus lose one-fifth of her weight in six hours 
without serious consequences. But the estimate 
was honestly made, and I stand by it. 
Landois and Sterling give the amount of 
blood in the body at one-thirteenth of the 
body-weight, and the total proportion of water 
to the weight of the body at 58.5 per cent. 
It is not to be supposed that all the water 
excreted during a pilocarpine sweat comes 
from the blood at one time. As it is taken 
out of the blood it is replaced from other 
tissues by reabsorption. 
One important point in the diaphoretic 
action of pilocarpine is the fact that the 
amount of urea excreted by the skin is greatly 
increased. This amount is stated to be not 
less than one gramme (fifteen grains) for each 
"sweat," which is five times more than in 
normal perspiration (H. C. Wood). 
The importance of this fact is recognized 
in the usefulness of pilocarpine in uraemia, 
and is markedly illustrated in the above case. 
After three or four days of anuria, uraemic 
symptoms became intense, and were relieved 
by pilocarpine. 
The discharge from the bronchial mucous 
membrane is largely increased. This also has 11 
an important clinical significance in two 
ways: 
1. It is this effect that makes it useful in the 
treatment of diphtheria, in which disease it de- 
taches and softens the membranes by the liquid 
exudation beneath them, so that they can be ex- 
pelled. This statement is not theoretical, but 
is a clinical fact, and were it not for the depress- 
ing action of the drug on the heart, it would 
undoubtedly be of great value in that disease. 
2. The second clinical significance of this 
action on the bronchial mucous membrane is 
that it points out a contraindication, as in 
cases where bronchitis or oedema of the lungs 
exists there is danger of drowning the patient 
in his own secretions. 
But whatever may be the physiological 
action, as shown by experiments on animals, 
the clinical effect on the heart constitutes the 
main contraindication and principal danger of 
its use in disease. Many cases have occurred 
where fatal results from cardiac failure have 
followed its use in disease. 
One notable case occurred in Dublin, Ire- 
land, some years since, where a physician ad- 
ministered pilocarpine in malignant scarlatina. 
The patient promptly died, and the doctor was 
called upon to defend an action at law for 
having killed the child. 
A similar case came under my own observa- 
tion, without, however, the unpleasant sequel. 
So, also, in dropsy with weak heart, espe- 
cially dropsy due to heart-disease, care must 
be taken, in the use of the remedy, to admin- 
ister stimulants freely at the same time. 
Action on respiration follows that on the 
heart, dyspnoea accompanying the intense pal- 12 
pitation, and later there may be embarrass- 
ment from accumulation of mucus in the 
bronchial tubes. Temperature falls 0.90 during 
sweating stage (Brunton). 
Another action of pilocarpine, which is men- 
tioned only as a caution, is its effect in pro- 
ducing abortion. This is a frequent result 
where given in full dose during pregnancy. 
In like manner, also, it may produce prema- 
ture menstruation or precipitate menorrhagia. 
Bartholow mentions four cases in which 
labor was induced by three hypodermic injec- 
tions of two centigrammes each ; and out of nine 
cases where it was used for this purpose, it was 
successful in six. 
General Diseases in which Pilocarpine 
is Useful. 
Of renal origin. 
Of cardiac origin. 
Local dropsies,-e.g., hydro- 
thorax. 
Hydropericardium and ascites. 
i. Dropsies. 
Anuria from various causes. 
In Bright's disease. 
Puerperal convulsions. 
2. Urcemia. 
Especially such as are at- 
tended by dry, itching 
skin. 
Prurigo, pruritus senilis. 
Chronic urticaria, chronic 
eczema. 
j>. Diseases of 
the skin. 
4- Diphtheria. 
g. Diabetes insipidus. 
6. Galactagogue. 
7. To stimulate the growth of the hait 
8. As an antidote to serpent venom. 13 
1. In dropsies its value is evident from the 
amount of liquid excreted from the system. 
In renal dropsy and in local dropsy, such as 
hydrothorax, its value is particularly marked. 
In renal dropsy it relieves not only by taking 
water out of the system, thus causing its ab- 
sorption, but also by the large excretion of 
urea it causes, thus relieving the uraemia, as in 
the case before quoted. Another effect, es- 
pecially in acute nephritis, is to relieve con- 
gestion of the kidneys and restore them to 
action. 
It is desirable in administering the drug to 
wrap the patient in blankets and surround him 
with hot bottles, to increase the diaphoresis, 
and if he is exhausted, give a stimulant. 
In hydrothorax, hydropericardium, and as- 
cites the same method is to be employed. In the 
former the results have been especially satis- 
factory. In dropsies due to heart-disease, 
special care must be taken to guard against 
the depressing action. 
2. Urcemia.-Enough has already been said 
of its use in uraemia due to anztria, in the case 
quoted, to indicate its usefulness. In puerperal 
convulsions it has proved of great value. 
j. In diseases of the skin, particularly those 
attended by itching and in which the skin is 
dry. 
In one of the cases where it caused change 
of the color of the hair it was given suc- 
cessfully for the itching attending chronic 
Bright's disease, in dose of 20 to 30 drops of 
the fluid extract several times daily, for a year 
and a half. 
It caused moisture of the skin and relieved 
the itching. 14 
I have seen it give prompt relief in a case of 
obstinate urticaria after the usual remedies had ' 
failed. In this latter case there was a gouty 
rheumatic affection of the finger-joints, which 
disappeared while under its use. 
In another case of rheumatic gout of the fin- 
gers it was given successfully. So, also, in sub- 
acute and chronic rheumatism of other joints 
that resist ordinary treatment, pilocarpine is 
worth a trial on the basis of aiding the excre- 
tion of effete material from the system. 
In these cases it is given by the mouth, 
either in form of the fluid extract or of the 
alkaloid, just sufficient to cause moisture of 
the skin and slightly increased flow of saliva, 
and must be continued sufficiently long to 
get decided excretory action. 
4. In Diphtheria.-Dr. Guttman, of Cron- 
stadt, was the first to insist on the value of 
pilocarpine in this disease, and he claimed 
favorable results in a large number of cases. 
His observation was, not that it exerted any 
specific action in the disease, but that it 
loosened and softened the false membrane by 
its action on the mucous membrane beneath, so 
that the former was easily expelled. 
Following his report, Lax reported ten cases 
treated by pilocarpine alone, all of which re- 
covered. 
Later, Dr. E. C. Wendt (Med. Record, April 
9, 1881) reported three cases which recovered 
under pilocarpine after other reme'dies had 
failed. On the other hand, Neumeister pub- 
lished twenty-eight cases thus treated, with un- 
favorable results. Five cases were adults, 
twenty-three children. 
The adults appeared to be influenced favor- 15 
ably, but with the children, thirteen out of the 
twenty-three died, and in eight bad effects of 
the drug were observed. 
Neumeister's conclusion was that pilocarpine 
is a dangerous drug with children, and that its 
value in diphtheria is not sufficient to justify 
its use. 
In a disease so fatal as diphtheria, espe- 
cially the laryngeal form, any remedy which 
promises to avert the usual termination is wel- 
comed with avidity. 
The following case illustrates the most favor- 
able action of the remedy in this disease. It 
occurred in my practice shortly after Guttman 
published his cases. 
I give only a synopsis of the case. Charles 
S., aged fourteen months, strong, healthy child 
of German parentage. Had been ailing for sev- 
eral days previous to July 9, 1881, with hoarse 
cough. On this date I saw him, when voice 
was lost, and he was restless. 
July 10.-Breathing loudly stridulous ; voice 
entirely suppressed ; entire fauces were covered 
with ashy-white membrane. 
July 11, a.m.-Worse; dyspnoea and rest- 
lessness increased. Pilocarpine, 2 milligrammes, 
ordered to be given every hour, milk-punch 
ad lib. 
July 11, p.m.-No worse. 
July 12, a.m.-No worse. Turpeth mineral 
emetic given during night; dose of pilocarpine 
doubled. 
July 12, p.m.-Better; slept most of the 
day; stridulous breathing less marked; more 
cough and cough looser; sweating and saliva- 
tion very free; dose of pilocarpine reduced to 
original amount. 16 
July zj>, a.m.-Still better; passed comfort- 
able night, sleeping; stridulous breathing 
gone; false membrane has disappeared from 
the fauces. 
Jtily 13, p.m.-Still improving; cough 
troublesome, but loose; aphonia still present. 
July iy.-Still improving; slight return of 
voice; some appetite. 
July 18.-Diphtheria well; slight diarrhoea. 
When I first saw this case I considered it 
hopeless in the light of previous experience. 
It illustrates the most favorable action of pilo- 
carpine in diphtheria. 
I have tried it in many cases since, but with- 
out so favorable a result. 
The form of diphtheria in which pilocarpine 
is most useful is that known as membranous 
croup, in which the danger is from the local 
obstruction to respiration rather than from 
septic infection and exhaustion. In these cases 
it favors the separation of the membrane and 
consequent expulsion. 
y. Diabetes Insipidus.-In this disease it 
acts as a revulsive by attracting away from the 
kidneys the excessive secretion of water and 
directing it to the skin and salivary glands; 
and the habit once broken, it may not 
return. 
One case under my observation, a German 
blacksmith, aged about fifty years, had a sun- 
stroke in July, which was followed in October 
by diabetes insipidus. 
The amount of urine passed was very great, 
a large bucket being filled during the night, 
and as much more passed during the day,- 
about four gallons in twenty-four hours. 
The amount of water drunk was in proper- 17 
tion. The skin was dry and scaly, though in 
health he had always sweated freely. 
After trying other remedies without relief, he 
was ordered 4 grammes of the powdered leaves 
in infusion, the powder to be stirred up and 
drunk with the infusion at bedtime; at the 
same time the man was wrapped in hot blankets. 
The following morning I found him much 
exhausted, unable to rise from weakness. He 
had sweated and salivated all night. The 
blankets were soaked, the mattress soaked, 
and there was a puddle of water on the floor 
under the bed. But it was the end of the 
polyuria; the latter never returned. 
This case occurred over twenty years ago. 
There has been no return of the disease, and 
the man is still in good health for his age. 
6. As a Galactagogue.--Its action upon the 
mammary gland is analogous to its action upon 
the salivary and sweat glands, but in a much 
less degree. 
Many cases have been reported of its success- 
ful use when there was insufficient secretion of 
milk. 
For this purpose it is administered internally 
in doses just sufficient to produce its physio- 
logical action without excessive sweating and 
salivation. 
7. To stimulate the Growth of the Hair.- 
This it does by increasing its nutrition through 
the hair bulb. There are two methods of ad- 
ministration for this purpose,-one, the slow 
method, by small doses given by the stomach 
through a long period, in just sufficient amount 
to cause slight sweating and salivation ; the 
other, the rapid method by hypodermic injec- 
tions of one centigramme two or three times 18 
a week. (See reports by Schmitz, Scholler, 
Simon, and Pick, farther on in this paper, 
pp. 24 and 25.) 
8. The Action of Pilocarpus as an Antidote to 
Serpent Venom.-For the knowledge of this 
property of the drug, we are indebted to Dr. 
H. C. Yarrow, of Washington, D. C., and late 
herpetologist to the United States National 
Museum. 
The following letter from Dr. Yarrow ex- 
plains itself: 
" My dear Dr. Prentiss,-In answer to your 
inquiry as to the influence of extract of jabo- 
randi as an antidote to serpent venom, I. will 
state that my experiments at the United States 
National Museum at Washington, D. C., upon 
the venom of the rattlesnake, led me to believe 
that jaborandi has decided antidotal value, and 
its active principle, pilocarpine, doubtless 
would be even more efficacious. These ex- 
periments were carefully made upon dogs, rab- 
bits, and chickens, and it was conclusively 
shown that jaborandi, administered hypodermi- 
cally after the application of the venom, pro- 
tected against an otherwise lethal dose. So, 
also, did the administration of the drug inter- 
nally immediately after the poisoning. The 
details of these experiments were published in 
Forest and Stream for the year 1888. 
11 Very sincerely yours, 
" H. C. Yarrow, M.D." 
Action on the Eye. 
Brunton divides myotics (pupil contractors) 
into two classes : 
1. Those which act by stimulating the end- 
ings of the oculo-motor nerve, which supply 19 
the circular fibres of the iris,-viz., pilocarpine, 
muscarine, nicotine. 
2. Those which act directly on the circular 
fibres themselves,-viz., eserine. 
Pilocarpine contracts pupil and causes spasm 
of accommodation by stimulating the oculo- 
motor nerve-endings of circular fibres of the 
iris, and those to the ciliary muscle. 
Action upon accommodation begins after, 
and passes away before, that upon the iris. 
The effect on the eye, when applied locally, 
lasts about one hour and a half. 
Atropine, on the contrary, dilates the pupil 
and paralyzes the accommodation by para- 
lyzing nerve-endings of the oculo-motor, and 
stimulating the radiating fibres of the iris. 
The importance of these physiological actions 
is in their relation to intraocular pressure. 
I hope I may be pardoned a reference to the 
therapeutics of certain eye-diseases in this 
presence, where so many are already familiar 
with the subject in their daily work. But all 
of us are not specialists, and the reference is in 
the line of pilocarpine. 
Intraocular pressure is increased by the in- 
crease of fluid in the anterior chamber. As,- 
x. An increase in the amount secreted by 
the ciliary processes (aquus capsulitis). 
2. Interference with its exit through the 
canal of Schlemm into the perichoroidal spaces 
(glaucoma). 
3. Hyperaemia of the iris. 
Intraocular pressure is diminished by oppo- 
site causes. Pilocarpine and eserine diminish 
intraocular pressure by drawing backward 
and flattening the iris, so as to allow the fluid 
of the anterior chamber to escape through the 20 
spaces of Fontana and the canal of Schlemm 
into the perichoroidal spaces. 
An examination of the drawing, which shows 
both the normal and the glaucomatous eye, 
indicates the modus operandi of myotics in 
diminishing intraocular pressure. 21 
The diseases of the eye in which pilocarpine 
and other myotics are useful I will merely enu- 
merate : 
Diseases of Eye and Ear in which Pilo- 
carpine is Useful. 
Glaucoma. 
Hemorrhage into vitreous and 
retina. 
Detachment of retina. 
Floating bodies in vitreous. 
Vitreous opacities. 
Commencing atrophy of optic 
nerve. 
White atrophy (a specific, ac- 
cording to Gillet de Grand- 
mont). 
Paralysis of accommodation. 
Amblyopia from tobacco- or 
alcohol-poisoning {par ex- 
cellence). 
Chronic rheumatic affections 
of eyeball. 
Photophobia. 
To break up adhesions of iris 
to lens or cornea. 
Diseases of 
Eye. 
Diseases of 
Ear. 
Labyrinthine deafness. 
Aural vertigo. 
I have mentioned glaucoma first because it is 
a matter of so much importance to the general 
practitioner that he should be able to recog- 
nize it, and at least do no harm if a case comes 
to him. 
The majority of cases of glaucoma come first 
to the general practitioner, and the two symp- 
toms-hardness of the eyeball and rainbow 22 
colors around a light-should put him on his 
guard. If these symptoms are present, with 
dimness of vision and pain, better send the 
case to a specialist. 
But, of all things, do not put atropine in the 
eye. This last, unfortunately, is too often done, 
the case being mistaken for iritis, the result of 
which it is unnecessary to state to this audience. 
In all of these diseases the pilocarpine is use- 
ful, from one or all of its properties, in (i) re- 
ducing intraocular pressure, or (2) contracting 
the pupils, or (3) stimulating the muscle of 
accommodation. 
In commencing atrophy of the optic nerve, 
according to Gillet de Grandmont, it is almost 
a specific (Brunton's " Therapeutics"). 
In amblyopia from tobacco and alcohol also, 
it is credited with being a most valuable remedy. 
When used only to contract the pupil and 
stimulate accommodation, it may be dropped 
into the eye in solution. 
But when used in the graver internal dis- 
eases of the eye, it must be pushed to its full 
physiological action, and had best be adminis- 
tered hypodermically in dose of 1 centigramme, 
this being given once daily, or once in two or 
three days, according to the effect. 
In labyrinthine deafness and aural vertigo, 
success has been claimed in several cases. It 
is administered as above. He does not explain 
the manner in which it acts. 
Antagonism between Pilocarpine and 
Atropine. 
This is so well known that it needs but to be 
mentioned. 
Pilocarpine causes sweating and salivation 23 
and increases secretion of mucous membranes; 
contracts pupil and stimulates accommodation ; 
diminishes intraocular pressure. 
Atropine and jaborine are the opposite in 
every particular. 
The two are, therefore, physiological anti- 
dotes of each other. 
A pilocarpine sweat can be stopped by a 
hypodermic injection of atropine. In experi- 
ments on frogs, where the action of the heart 
has been stopped by pilocarpine, it can be re- 
stored by atropine. 
So, also, poisoning by belladonna, stramo- 
nium, or hyoscyamus can be, and has been, 
successfully treated by pilocarpine. Such cases 
have been mentioned by several writers. 
A case is reported in the Australia Medical 
Gazette (February 15, 1892, by Dr. Cortis) of 
a child, eighteen months old, who took four 
grains of sulphate of atropine and six grains of 
cocaine. Pilocarpine, ona-seventh of a grain, 
was injected, and shortly after repeated. 
There was immediate improvement and prompt 
recovery. 
The amount required*to antagonize a given 
dose of atropine is stated to be four times as 
much of pilocarpine. 
In the three following respects pilocarpine 
and atropine agree in action : 
1. In producing frontal pain. 
2. In producing pain in bladder. 
3. In affecting children less than adults in 
proportion. 
But these have no importance from a thera- 
peutic stand-point. 
We consider next the change in the color of 
the hair. 24 
One case I have above referred to. 
In another, a case of diphtheria in a very 
light-haired child, specimens taken before and 
after treatment show a decided change for the 
darker; but after a time the color appeared to 
fade. In this case the drug was only adminis- 
tered a few days. 
A third case was reported in a paper read by 
myself before the American Medical Associa- 
tion, June, 1889, which I draw upon largely for 
the following facts: 
Mrs. L., aged seventy-two years, suffering 
from Bright's disease, contracted kidney. Hair 
and eyebrows had been snow-white for twenty 
years. Suffered greatly from itching of the 
skin, due to the uraemia of the kidney-disease. 
Skin harsh and dry. For this symptom fluid 
extract of jaborandi was prescribed, with the 
effect of relieving the itching. It was taken in 
doses of 20 or 30 drops, several times a day, 
from October, 1886, to February, 1888. 
During the fall of 1887 it was noticed by 
the nurse that the eyebrows were growing 
darker, and that the hair of the head was 
darker in patches. These patches and the eye- 
brows continued to become darker, until, at 
the time of her death, they were quite black, 
the black tufts on the head presenting a very 
curious appearance among the silver-white hair 
surrounding them. A new growth of black 
hair also appeared on the scalp under the old 
hair. 
These are the only cases thus far recorded 
in which pilocarpine has been supposed to 
change the color of the hair. 
In 1879, Dr. G. Schmitz (Aerliner Klinische 
Wochenschriff, No. 4, 1879 1 Medical Bulletin, 25 
Philadelphia, 1882), of Cologne, reported two 
cases in which pilocarpine stimulated the growth 
of the hair in alopecia. One patient, aged sixty, 
completely bald. Pilocarpine subcutaneously 
for disease of the eye. After three injections, 
within a fortnight, the head became covered 
with a thick down, which grew rapidly, so 
that in four months no trace of the baldness 
was left. No mention is made of the color. 
In the second case, the patient, aged thirty- 
four, had a bald patch on top of the head the 
size of a playing-card. Total restoration of 
the hair after two injections, in a short 
time. 
Scholler {Klebs's Archiv, tells of simi- 
lar results in animals in which alopecia had 
been produced by injections of bacteria. 
Oscar Simon {Berliner Klinische Wochen- 
schrift, 1879) relates the case of a woman, aged 
thirty. General alopecia,-head, eyebrows, 
eyelashes, axillae, and pudenda. In a few 
weeks, after twenty injections of pilocarpine, 
the lanugo of the whole body was restored. 
In other cases so treated there was no effect 
whatever. 
Professor Pick {VierteljahrschriftfiirDermat. 
und Syphil., 1880) relates the case of a man 
who was afflicted with alopecia areolata. Two 
weeks after pilocarpine injections followed a 
fine colorless lanugo, and in twelve weeks 
restoration of the hair. 
Ten cases of alopecia pityrodes; favorable 
results from same treatment. Color of hair 
not mentioned. 
Landesberg {Medical Bulletin, Philadelphia, 
1882), of Philadelphia, says that in more than 
one hundred cases of eye-disease treated by 26 
pilocarpine he observed no effect whatever 
upon the growth of the hair. Dose and mode 
of administration not mentioned. 
In 1882, Julius Pohlman, of Buffalo, experi- 
mented on white rabbits by hypodermic injec- 
tions of pilocarpine. The dose used was large, 
-1 grain three times a day. No change in 
color was noted in pure white rabbits. In 
parti-colored animals,-white and brown,-in 
one a brown spot on back of head deepened 
and spread to a remarkable degree down the 
back and sides of the animal to the legs. In 
other individuals no change was noticed. Post- 
mortems on these animals showed enlarged 
spleen and altered suprarenal capsules. 
The question of change of color of the hair 
is an interesting one, both from a physiologi- 
cal point of view and from the practical one of 
pathology. 
The physiological aspect embraces the ques- 
tion of how a change of color takes place,- 
whether in existing hairs, or produced by 
shedding of the hair and a new growth taking 
its place of a different color. 
It has been doubted by good authority- 
Hebra and Kaposi-if the hair, after being 
once developed, can change except by a very 
gradual process. This doubt is based upon the 
theory that the hair has no vascular or nerve- 
connection with the general system, and must, 
therefore, be independent of nervous or sys- 
temic influence. This position is, however, 
not tenable. The clinical evidence is positive 
that the hair does change color under systemic 
influences, sometimes gradually and sometimes 
suddenly. 
We hear frequently of the hair turning white 27 
in a night from violent emotions, as fright, 
great grief, or great joy, and it has come to be 
a method of expressing extreme emotion to say, 
" It was enough to turn one's hair white." 
I say it is not an uncommon thing to see 
mention of such cases in popular literature, 
but well-authenticated cases are not so often 
found. It is recorded in history that the hair 
of Marie Antoinette and Mary Queen of Scots 
became white suddenly from the horrors to 
which they were subjected. 
A short time since, in conversation with an 
eminent microscopist and pathologist,* I asked 
how he would explain, from the basis of minute 
anatomy, the sudden change in color of the 
hair. He replied that he did not explain it; 
that he did not believe it happened; that the 
reported cases were not authenticated. He 
further said that, from the structure of the hair 
and its relation to the skin, he considered it 
impossible. 
Duhring (third edition) is authority for the 
statement that Hebra and Kaposi discredit 
sudden canities. There is, nevertheless, no 
doubt of the fact that such change does some- 
times occur, and to set the matter definitely at 
rest, I looked up the subject in the library of 
the Surgeon-General's office. The following 
are some of the references found : 
Dr. Wm. P. Dewees (" Phila. Med. Mus.," 
1807, vol. iii. p. 219), of Philadelphia, reports 
a case of puerperal convulsions under his care. 
From 10 a.m. to 4 p.m. fifty ounces of blood 
were taken. Between the times of Dr. Dewees's 
visits-not more than an hour-the hair anterior 
* Dr. William M. Gray, Army Medical Museum. 28 
to the coronal suture turned white. The next 
day it was less light, and in four or five days 
was nearly its natural color. 
He also reports two cases of sudden blanch- 
ing from fright. 
Dr. Robert Fowler (London Lancet, 1853, 
p. 556) reports the case of a girl sixteen years 
of age, apparently in good health, hair black; 
found one morning, in combing her hair, that 
a strip the whole length of the back hair was 
white, starting from a surface two inches square 
around the occipital protuberance. Two weeks 
later she had patches of ephelis over the whole 
body. 
In the Canada Journal of Medical Science, 
1882, p. 113, is reported a case of sudden 
canities due to business worry. Microscope 
showed a great many air-vesicles both in the 
medullary substance and between the medullary 
and cortical substances. 
Dr. Graves says most authors are of the opin- 
ion that the hair, once formed, is independent 
of the organism, with which opinion he dis- 
agrees, instancing Plica Polonica as opposed to 
such a theory. He states five cases sustaining 
his Views. (See Dublin Quarterly Journal, 
of Med. Sci., 1847.) 
In the Boston Med. and Surg. Journ., 1851, 
is reported a case of a man, thirty years old; 
hair scared white in a day by a grizzly bear. 
Was sick in a mining-camp ; was left alone, and 
fell asleep. On waking found a grizzly bear 
standing over him. 
A second case. Man of twenty-three years 
was gambling in California. Placed his entire 
savings of eleven hundred dollars on the turn 
of a card; was under tremendous nervous ex- 29 
citement while the cards were being dealt. 
He won. The next day his hair was perfectly 
white. 
In the same article is the statement that the 
jet-black hair of the Pacific islanders does not 
turn gray gradually; but when it does turn, it 
is sudden, usually the result of fright or sudden 
emotions. 
The following cases are of change of color 
from white to black : 
Dr. Bruley (Boston Med. and Surg. Journ., 
1852, p. 406), physician to the Fontainebleau, 
reported to the Societe Medicale, Paris, in 1798, 
the case of a woman, sixty years old, whose 
hair, naturally white and transparent as glass, 
became jet black four days before her death 
(phthisis). On examination after death the 
bulbs of the black hairs were of immense size 
and engorged with dark pigment. The roots 
of white hairs that remained were dried up and 
two-thirds smaller in size (Wilson, " Skin- 
Diseases," p. 377). 
Dr. Alanson Abbe (loc. citj mentions the 
case of Dr. Capen, who had become gray ; but, 
on recovery from disease, his hair became quite 
dark. 
In the St. Louis Med. andSurg. Journ., 1845, 
p. 310, there is reported the case of an old man, 
eighty-one years of age, robust and hale. Hair, 
from being perfectly white, became black ; same 
of the beard. This man also presented the 
phenomena of second sight; could read readily 
without glasses. 
The text-books on skin-diseases also mention 
cases. Several cases of sudden canities are re- 
ferred to in Ziemssen. 
Brown-Sequard, in his own person, noticed 30 
one day a white hair in his beard where there 
was none the day previous. He pulled it out, 
and the next day others appeared. 
This was observed repeatedly, and there was 
no doubt that the hair in its entire length 
turned white in one night. Under the micro- 
scope these white hairs showed small air-bub- 
bles in place of the normal pigment. 
In a case of hemiplegia, the hair became 
white on the paralyzed side. The same has 
been reported in cases of neuralgia. 
Other anomalous cases have been noted 
where the hair became white in patches, and 
where individual hairs have been seen alter- 
nately white and black at different stages of 
its growth, to which condition Karsh and 
Landois have given the name of ''ringed 
hair," and ascribed it to an intermittent 
trophic disease affecting the hair-follicle. 
Wilson mentions a case where the hair was 
gray in winter and regained its normal color 
in summer. 
Alibert (foe. citP) and Beizel relate cases of 
women with blonde hair which all came out after 
severe fever, and when new hair grew, it was 
black. Alibert also relates the case of a young 
man who lost brown hair during illness, and 
that which replaced it was red. In the case of 
an epileptic girl of idiotic type, with alternating 
phases of stupidity and excitement, during 
the stage of stupidity the hair was blonde; 
during excitement it was red. This change of 
color took place in two or three days, the 
change always beginning at the end of the 
hairs. Pale hairs showed an increased number 
of air-spaces. 
It has been frequently observed that when 31 
the hair changes color gradually, the change 
begins in the end and extends towards the 
bulb. 
In conversation with an eminent ornithol- 
ogist* on the change of color in the plumage of 
birds, he said, "I have lately been watching 
hairs in my moustache turn gray, and it al- 
ways begins at the ends and extends to the 
roots." 
Speaking on the subject with a lady (the 
one who furnished the specimens here shown), 
she mentioned the case of the physician who 
attended her at the sea-shore some years ago, 
The doctor's hair was long and quite gray. 
One day he came in to see her after having his 
hair cut, dnd she was surprised to notice that 
the gray hair had given place to black. Ex- 
amination showed that his hair towards the ends 
had been white, and that nearer to the skin 
black. The white portion had been removed 
by the cutting. This phenomenon may fre- 
quently be noticed, attention having once been 
called to it. 
The cases here collected are only a few in 
comparison to what might be found, but they 
are sufficient to prove beyond all reasonable 
doubt that the hair does suddenly change color 
under certain circumstances, and that the change 
takes place in existing hairs. 
Analogous to changes in the color of the hair 
in man are the changes which occur in the lower 
animals. In animals and birds such changes 
are often periodical, as in their summer and 
winter coats. This occurs to a very marked 
degree in a great many species. Thus, the 
* Professor Robert Ridgway, Smithsonian Institution. 32 
ermine in summer is dark brown, in winter 
pure white, with only the black tip to the 
tail. 
Among birds, the ptarmigan is white in win- 
ter and brown in summer. So with our famil- 
iar bobolink: yellow in fall, in spring black 
and buff. 
As to the question whether, in birds and 
animals, this change takes place in individual 
feathers and hairs, or whether all the old 
plumage and fur is shed by moulting, recent 
investigations favor the view that it is due to 
both. Dr. Elliott Coues Fur-Bearing Ani- 
mals") says it may be either or both. Mr. 
Robert Ridgeway (Smithsonian Institution) in- 
clines to the opinion that in birds it is accom- 
plished by moulting. 
Dr. Louis Stejneger (Smithsonian Institution) 
was formerly of the same opinion, but recent 
studies have inclined him to the belief that 
there is also a change in the color of existing 
feathers. He was led to this change of belief 
by a critical study of the changes in color of 
the black and white fly-catcher of Europe, and 
especially from an examination of a series of 
twenty-seven specimens of the narcissus fly- 
catcher {Xanthophygalia narcissincp) of Japan. 
His studies in full appear in the " Proceedings 
of the United States National Museum, 1889." 
Dr. C. Hart Merriam, Ornithologist of the 
Agricultural Department, in a letter dated 
June 12, 1889, says, "The change from fall 
to spring plumage in birds is due to moult, 
without exception, as far as I am aware. In 
the case of mammals the matter is now in dis- 
pute. Probably in the majority of cases it is 
due in part to moult and in part to actual 33 
change in the color of existing hairs. . . . 
The change in color from immaturity to ma- 
turity is always due to the growth of new hairs 
or feathers." 
That the change in birds and mammals is 
due, in part at least, to change of existing 
coats seems established. Sometimes this change 
is almost sudden, as where the change of season 
is very abrupt. In such case, of course, there 
would not be time for the growth of new hair 
or plumage. 
In the golden plover (Charadrius doniinicus'), 
the black belly of summer changes to white in 
winter. While this change is taking place, in- 
dividual feathers, part black and part white, 
may be seen. 
In Bonaparte's gull, a common gull of our 
coast (Larus Philadelphia'), the black of the 
head of summer changes to white in winter, 
principally by change in color of existing 
feathers (Ridgway). 
Another interesting feature of this question, 
as bearing on the change in the color of the 
hair by drugs, is the influence of certain sub- 
stances administered as food, in changing the 
color of tissues in some of the lower orders. 
In orange canaries it has come to be an 
established fact that, by feeding the parent 
birds with a certain kind of food, the active 
ingredient of which is cayenne pepper, the off- 
spring will be of an orange color, and orange- 
colored canaries may be seen in the stores of 
most bird-fanciers. A food for producing 
orange canaries is extensively advertised by a 
bird-dealer in Baltimore (Bishop). It is re- 
ported that the Indians of the Amazon cause 
green parrots to change to yellow and red by 34 
feeding them upon the fat of a certain fish 
allied to the shad (Wallace's "Amazon"). 
Dr. Merriam, in the letter previously quoted, 
says, "It is well known that food affects the 
color in birds. Red purple finches and pine 
grosbeaks invariably turn yellow when caged. 
This is due undoubtedly to the absence of some 
important food element. 
"In some of the zoological gardens of 
Europe it is the custom to send roseate spoon- 
bills and flamingoes to Amsterdam Garden to be 
recolored. The particular food by which Mr. 
Westermann accomplishes this end is a secret, 
but it is believed to be a kind of shrimp or 
small crustacean which has a quantity of red 
pigment in its shell." 
In the same direction are the changes of 
color in other tissues by particular foods. It 
has long been known that when pigs are fed on 
madder, their bones become red. This fact 
has been taken advantage of by physiologists in 
studying the structure and development of bone. 
The phosphate of lime acts on the coloring- 
matter of madder as a mordant. When given 
intermittently to a growing animal, the bone 
presents alternate rings of red and white. 
Darwin (" Origin of Species") mentions that 
pigs in Virginia eat the paint-root (JLachnanthes 
tinctorial) and their bones are colored pink, and 
it causes the hoofs of all but the black varieties 
to drop off. " From facts collected by Heu- 
singer it appears that white sheep and pigs are 
injured by certain plants, wrhile dark-colored 
individuals escaped. . . . On asking some 
farmers in Virginia how it was that all their 
pigs were black, he was informed that the 
black members of a litter were selected for 35 
raising, as they only had a chance of living." 
Any one travelling through Virginia can verify 
this statement by noticing the preponderance 
of black pigs in that State. 
Fleurens (1824) made use of madder for 
coloring the semicircular canals of pigeons, to 
outline the canals more distinctly. (See, also, 
Ferrier on "Functions of the Brain," and the 
writings of Vulpin, the French physiologist.) 
Mr. Lucas, osteologist of the National Mu- 
seum, informs me that the bones of the crow 
are made purple by feeding on pokeberries. 
Ridgway says the bones of the Western fox 
squirrel are red, while those of its Eastern 
brother are white. No cause has been assigned 
for the difference. 
See, also, experiments by Marci Paolini in 
1141. ("Specimen quorundam experimento- 
rum de vi Rubise ad ossa ovorumque Gallina- 
rium putamina calcariae coloranda. " No. 1 of 
" Miscellani Medichi," pamphlet vol. 1149.) 
He gives a very good plate of the colored 
skeleton of a fowl, and also of its colored egg 
after four months' feeding Rubia tinctorium. 
He also gives references to other authorities, 
the most satisfactory of which is Belchior 
("Philosophical Transactions," vol. ix., 1732), 
who gives an account of feeding hogs and 
fowls with madder-root and wheat-meal. A 
rooster so fed died in sixteen days, and showed 
the condition admirably. Other writers take 
up the subject after him in the same pub- 
lication. 
It is reported that among workers in cobalt 
and indigo the hair becomes blue; also in 
artisans working with copper the hair takes a 
greenish hue. 36 
The color of butterflies can be changed ac- 
cording to the food upon which the caterpillars 
are fed. More remarkable still, perhaps, is the 
change of color in the chameleon and in many 
insects, according to the color of the substance 
with which they are in contact. 
The environment undoubtedly has a power- 
ful influence upon the coloring of animals 
and birds. This is clearly illustrated in every 
museum of natural history. Specimens from 
arid desert regions are uniformly of a dull, 
faded appearance compared with those from 
regions of luxuriant foliage. 
M. G. Touchet (" Transactions of British 
Association for the Advancement of Science," 
1872, p. 152), in his work entitled " Mechanism 
of Change of Color in Fishes," says that it is 
due to the size of contractile color-cells placed 
in the skin. These are under the influence of 
the nerves. The author found that the par- 
ticular nerves controlling them (in the turbot) 
were nerves of the sympathetic system. By 
cutting the nerve supplying a particular area 
of the skin he had been able to retain that 
area unchanged in color, while the rest changed 
as the fish found itself on a dark or light sur- 
face. 
That the eye is the means by which this 
change in its condition is communicated to the 
fish or crustacean, and that reflex action then 
takes place through the sympathetic nerves on 
the color-cells of the chromatophors, is proved 
by the fact that when the animal experimented 
on is blinded, no further change of color occurs 
when it is removed from light to dark, or the 
opposite. 
See, also, the Monthly Microscopical Journal, 37 
1871, vol. vi., M. G. Pouchet, on "Study of 
Connection of Nerves and Chromoblasts" 
(principally in fishes and batrachians). 
The reasons assigned by naturalists for peri- 
odical change in color of plumage or fur are 
twofold : 
1. Sexual selection. 
2. As a protection against enemies. 
1. Sexual Selection.-The male takes on a 
brighter and more attractive appearance to 
facilitate the business of courtship and the 
securing of a mate. 
2. As a Protection against Enemies.-In 
Arctic regions birds and mammals are usually 
white in winter, the color of the snow, so that 
they are with more difficulty found by their 
enemies. 
Darwin supposes that originally only a few 
individuals took on this change, and these 
being better protected, gradually, by a process 
of natural selection, only the white variety was 
left. 
It is apparent from what has been said that 
there is very much concerning the changes of 
color of the hair and other appendages of the 
skin in man and the lower animals that is not 
understood. In its normal condition the color 
of the hair is dependent upon the hair-bulb. 
It is here that the melanine is secreted from 
the coloring-matter of the blood, and from this 
point, as the hair grows, it permeates its cells, 
the intensity and shades, from black to blonde, 
depending principally upon the amount of the 
coloring-matter. 
In black hair the hair-bulb is larger, con- 
tains a greater amount of melanine, and the 
hair itself is coarser and of more vigorous 38 
growth. In those cases where the hair has 
turned from white to black, and minute exam- 
ination has been made, this has been found true. 
In the case reported by Bruley, already re- 
ferred to*, of a woman, aged sixty, whose hair, 
previously white, became jet black four days 
before her death, the bulbs of the black hairs 
are described as being of immense size and en- 
gorged with dark pigment, while the roots of 
the white hairs that remained were dried up 
and two-thirds smaller in size. 
So, on the other hand, in change from dark 
to white, the hair is finer in texture, less vigorous 
in growth, and the hair-bulbs smaller. 
The sudden change in canities, when due to 
violent emotions, can be explained in no other 
way than through the bulb. It is true that 
there is no direct vascular or nerve connection 
between the bulb and its hair after it emerges 
from the skin; but it is also undoubtedly true 
that there is communication by osmosis be- 
tween the cells of the papilla and those of the 
shaft and different layers of the hair. 
Wilson (" Lecture on the Skin") ascribes the 
cause of sudden whitening of hair to insuffi- 
cient nutritive power of the skin ; also suggests 
that there may generate a gaseous fluid in the 
hair in place of its normal constituents. 
He says, further, that the fluids from the 
blood-vessels of the skin permeate the hair, 
and thus change in fluids may alter color. 
In all of the cases of sudden change to white, 
where the hair has been examined, the coloring- 
matter has disappeared, and in its place is 
found an accumulation of minute air-globules. 
The same is true of gray hair of advancing 
age. How the air gets into the capillary struct- 39 
ure has never been explained. Two possible 
explanations are offered: 
One is that in the destruction of the color- 
ing-matter a gaseous substance may be de- 
veloped. This hypothesis has received no sup- 
port from observation. The other is that air 
finds entrance from without through the sides 
or end of the hair. 
It is possible to suppose a condition of the 
bulb producing a vacuum in the hair-shaft that 
shall cause, by suction, a drawing in of air. 
This theory, which is proposed for the first 
time by the writer, I believe to be the true 
one, as explaining not only sudden canities, 
but also the gradual senile change to gray hair. 
The view that the air finds entrance through 
the end of the hair is supported by the fact that 
the change of color begins at the extremity, 
and also by the observation that in all cases of 
change to white from dark hair the coloring- 
matter has been found to be replaced by air- 
vesicles. 
The erector pili muscle has an important 
influence on pathological changes which take 
place in the hair-bulb. 
This minute muscle has its origin in the true 
skin, and, passing downward, is inserted into 
the base of the hair-bulb, so that when it con- 
tracts it lifts the hair outward and compresses 
its papilla. 
The effect of sudden fright causes the hair to 
"stand on end" by contracting this muscle. 
Temperature has its influence with animals and 
birds. In cold weather (winter) the change is 
to white, in summer to black. 
Cold, we know, contracts the skin, and thus 
probably causes pressure on the hair-bulb. 40 
That the hair is easily influenced by external 
causes, as well as those which come through its 
bulb, is fully demonstrated. The mere fact 
that it can be so readily dyed and bleached 
artificially shows that the agents used for this 
purpose penetrate its substance. 
Bleaching agents, such as chlorine, per- 
oxide of hydrogen, and strong alkalies, act by 
removing the coloring-matter and not by add- 
ing any whiteness of their own. 
It remains to say a few words upon the sub- 
ject of changing the color of the hair by sub- 
stances taken internally, and as this paper has 
already exceeded the limit I had set for it, I 
shall be brief. 
1. In the human subject the only agent, so 
far as I am aware, which has been charged 
with changing the color of the hair, when 
taken internally, is jaborandi. Of this suffi- 
cient has already been said. 
2. Cayenne pepper in changing the color of 
canary-birds to orange. 
This is a well-known fact to bird-fanciers. 
I tried in Washington to get a specimen to 
show you, but was told it was not the season 
for them,-that they came in the autumn; also 
that they soon relapsed to their original color 
unless the Cayenne pepper food was kept up. 
3. The change of color in parrots by the 
Indians of the Amazon, from green to yellow 
or red, by feeding the fat of a certain kind of 
fish (Wallace's "Amazon"). 
4. The restoration of certain birds to their 
original brilliant colors at the zoological gar- 
den, Amsterdam, by feeding a kind of shrimp 
or small crustacean. 
5. As analogous to the above, the effect of 41 
madder in staining the bones of pigs red and 
of pokeberries coloring crows' bones purple. 
It might be of interest, did time admit, to 
study the influence of diet and habit upon the 
color of hair in different nations of men, as, 
for instance, why the Saxons have light hair 
and the Gauls black hair. 
It is within the bounds of possibility also 
that discoveries may be made in the future by 
which the color of the hair in the human race 
may be modified by judicious treatment of the 
parents. 
Some colors of hair are not popular, espe- 
cially with ladies, and it is not likely that 
Cayenne pepper will ever become a favorite to 
produce the orange hue. JANUARY 16, 1893. 
WHOLE SERIES, VOL. XVII. No. I. THIRD SERIES, VOL. IX. 
THE 
Therapeutic Gazette 
A MONTHLY JOURNAL 
- OF- 
General, Special, and Physiological Therapeutics. 
GENERAL THERAPEUTICS, 
H. A. HARE, M.D., 
. OPHTHALMIC ANO AURAL THERAPEUTICS. SURGICAL m GENITO-URINARV THERAPEUTICS, |l 
: 'i O. E. DE SCHWEIN1TZ, M.D., EDWARD MARTIN. M.D., 
| Clinical Professor of Ophthalmology tn the Clinical Professor of Genl to Urinary Diseases, University of I 
Jefferson Medial CoUegc. Peonaylvama. 
EDITORIAL OFFICE, 222 South Fifteenth St., Philadelphia, U.S.A, 
GEORGE S. DAVIS,. DETROIT, MICH., V.S.AM 
714 Filbert Street. Philadelphia. Pa. 
Published on the Fifteenth Day of Every Month. 
SUBSCRIPTION PRICE, TWO DOLLARS A YEAR. 
! Agent for Great Britain: Mr. H K. LEWIS, Medical Publisher and Bookseller, 136 Gower Street, London, W. C. I 
co,in,ic,<T't893, Cs°ro,: s- d*v"- I