Vol. XXIV. No. lo.] 
POPULAR SCIENCE NEWS. 
159 
nearer the blue — lying between E and F. 
When all these various characteristic spectra are 
given, the presence of hemoglobin and its deriva- 
tives, and hence of blood, is proven beyond 
question. Thus we see that the spectroscope tells 
us whether a given stain is or is not blood, but 
it will not differentiate between the blood of the 
various animals, or between the blood of these and 
that of man. But by means of the microscope we 
can tell by the red corpuscles whether the blood 
is that of a mammal or not, and this is of some 
importance in medico-legal cases; for, if a prisoner 
asserts that a stain found on a weapon or garment is 
from the blood of a fish or bird which he has been 
cleaning or otherwise come in contact with, it may, 
perhaps, be shown by means of the microscope that 
the man has lied, — if it be a stain from the blood 
of man or other mammal, — and, while such a cir- 
cumstance could not convict of murder, etc., still it 
would convict of falsehood, which in such a case 
would have some burden of evidence. 
When garments containing blood-stains have 
been boiled, the hiemoglobin is broken up, and a 
stain may remain which is insoluble in water, alco- 
hol, and ether; and yet it is possible for such a stain 
to be shown to have been caused by blood, by the 
formation of hamin crystals. Scrape off a portion 
of the stained fabric and place it on a glass slide, 
together with a few crystals of common salt; cover 
these with a cover-glass and apply glacial acetic acid 
under it. Heat the slide and carefully evaporate the 
acid mixture to dryness, after it has boiled. If the 
stain has been blood, a number of small, dark-red, 
rhombic crystals may be seen, with the microscope, 
to have been produced. Ilitmin crystals are char- 
acteristic, and when obtained are sufficient to 
identify a stain as blood. This is a most certain 
and delicate test for the determination of the 
presence of blood. II;emin crystals may be ob- 
tained in large numbers for examination and study 
by substituting a drop of blood for the stained 
fabric in the test just described. J. H. E. 
THE TENTH INTERNATIONAL MEDICAL 
CONGRESS. 
Of the Ninth International Congress, held at 
Washington, three years ago, the News gave an 
extended account prepared on the spot by a special 
correspondent. For a report of the Tenth, held at 
Berlin from August 4 until August 9, it must depend 
upon various sources of information. All accounts 
are agreed that it was in most, if not in all respects, 
an unqualified success. For one thing, it was the 
largest ever held, exceeding the very large gathering 
in London six years ago. 
The official register of names states that there 
were 5.737 members. These were accompanied by 
more than 1,000 ladies; while, in addition, 143 
persons were registered as taking part in the Con- 
gress, although not as actual members. Berlin 
opened its doors to this large assemblage of stran- 
gers, and the citizens received into their homes those 
whom the hotels could not admit. Of the foreign 
members of the Congress, the largest number, 659, 
came from the United States; 429 were from Russia, 
358 from Great Britain, and 179 from France. It 
was feared, until the last moment, thatr the French 
would find it impossible to so far forget national 
strifes as to join in the amicable pursuit of science. 
The president of the Congress was Prof. Rudolf 
Virchow, among the foremost medical men of the 
world, perhaps the foremost living pathologist. He 
delivered a very cordial address of welcome, in 
which he referred to American physicians as 
follows: "We, in Germany, have great admiration 
for the American medical world, which today excels 
in surgery, midwifery, and dentistry. I can say for 
myself and colleagues, that the American contingent 
will be honored and heartily welcomed. We admire 
their scientific zeal, and begrudge them their extra- 
ordinary skill, and shall try to imitate their push and 
energy. I find these latter virtues in the American 
student as well as in the finished scientist. My 
German students generally spend a few semesters 
deciding what line of medicine they shall follow, 
while the American student walks into the arena 
with a fixed purpose, and an indomitable determina- 
tion to accomplish it. This is why your men secure 
the laurels before their hair turns gray." 
A great number of papers were read in the 
various sections, some few being of considerable 
interest. The section meetings were, for the most 
part, held in the Exhibition building, where venti- 
lation was defective and much suffering was caused 
by the heat. The halls opened one into another, 
and much confusion was created by the passing 
of persons to and fro through the building, the 
noise sometimes being so great that it was impos- 
sible lo hear the speaker when sitting at a little dis- 
tance. 
Unfavorable comment was made by some that 
papers in the German language only were listened 
to with attention. During the reading in French 
or English, the German members left the meeting or 
walked about and conversed, thus causing great 
annoyance to the speaker and to those who desired 
to listen. In one section the member appointed to 
read a paper in English refused, saying it would not 
be listened to, and he did not wish to waste his time. 
The paper was therefore read by title. 
On Thursd.iy evening balls were given in honor 
of the Congress. On account of the large number 
of guests it was found impos-ible to entertain all 
in one place, so five different balls were given, in the 
Central Hotel, Kaiserhof, Imperial Hotel, the Phil- 
harmonic and the Zoological Garden, all being well 
attended. 
Friday aflernoon there was a court reception given 
to about 500 selected guests, and several sections 
made excursions to Potsdam and the lakes of Havel. 
Friday evening, as also every evening during the 
week, various private dinners and receptions were 
given by Berlin physicians to specially invited 
guests. Many sections were also entertained by 
resident chairmen or special medical societies 
of Berlin. 
The Empress Frederick visited the Exhibition 
Saturday morning, accompanied by a maid of 
honor, and was escorted through by the committee. 
It is well understood, of course, by men conver- 
sant with such things, that mere size does not mean 
success, more likely sound. To all gatherings 
of this sort are drawn scientific adventurers, men 
who have axes to grind and trumpets to blow, hon- 
est bores and dishonest pretenders, in addition to 
the vast array of ordinary men and the far smaller 
number of able ones. It is, perhaps, only in the 
way of the cultivation of a spirit of kinship and 
cordiality that much is accomplished by monster 
conventions of this kind. Still there were certain 
notable papers read, among which was one by the 
world-famous Dr. Koch, the discoverer of the bacil- 
lus tuberculosis. He stated, among other things, 
that he had been able, by appropriate treatment, 
to prevent the death of guinea-pigs and rabbits 
after inoculating them with pure cultures of tubercle 
bacilli. He gave no detailed statement of the nature 
of his experiments or of the medicines employed, 
as his work was not entirely completed ; but it is 
whispered that the drug that he has found so 
efficient is a salt of cobalt. When it is considered 
that guinea-pigs, are, perhaps, the most susceptible 
of all animals lo the ravages of the bacillus tuber- 
culosis, and that Koch is one of the most cautious 
of all investigators, — one who may be said to have 
never made a mistake nor been obliged to retract a 
word of his statements, — the significance of this pre- 
liminary communication may be appreciated. If 
there are germicide agents capable of arresting 
tuberculosis in dumb animals, there is, of course, 
some reason to hope for the discovery of the means 
of arresting or preventing tuberculosis in man, 
which m.ty fairly be said to be the one over-shadow- 
ing medical desideratum of the present time. 
Sir Joseph Lister, of London, the exponent, if not 
the discoverer of so-called Listerism, or antiseptic 
septic surgery, delivered an address upon the present 
position of antiseptic surgery. He dwelt at some 
length upon the theories of immunity developed 
from results of bacteriological studies, referring 
especially to Metshnikoff's hypothesis that patho- 
genic micro-organisms are destroyed by certain cells 
called phagocytes. He then gave a review of the 
origin and development of antiseptic surgery, tak- 
ing occasion to declare himself a firm upholder 
of antiseptic in contrast to aseptic methods, although 
the latter were not without their uses. He main- 
tained, however, that strict cleanliness, as insisted 
upon by Lawson Tail, and the use of boiled water 
were really antiseptic measures. The speaker had 
modified in many w.-iys his original methods, had 
wholly abandoned the spray, and fell ashamed that 
he had tried, and advised others to try, to destroy 
the microbes in the air. He was a believer in the 
efficacy of sublimate solutions and used them in 
strengths ranging, according to circumstances, from 
one In five hundred to one in ten thousand. He 
then referred to special indications in the antiseptic 
treatment of thoracic fistulas, contused wounds, 
joint injuries, etc., and closed with the reaffirmation 
of his belief in the necessity of antiseptic as opposed 
to so-called aseptic surgery. 
Another important paper was that read by Dr. H. 
C. Wood, of Philadelphia, upon aniesthesia, doubly 
important for its delivery upon the Continent, where 
chloroform still is the favorite surgical aniesthetic. 
Prof. Wood claimed that the following facts in re- 
gard to aniEsthesia muet be regarded as established : 
First, the use of any anaesthetic is attended with 
appreciable risk, and no care will prevent occasional 
loss of life; second, chloroform acts much more 
promptly and powerfully than ether, both upon the 
respiratory center and upon the heart ; third, the 
action of chloroform is more permanent than that 
of ether; fourth, chloroform is capable of arresting 
primarily either respiration or cardiac action, but 
usually abolishes both functions at about the same 
lime; fifth, ether usually acts more powerfully upon 
the respiration than upon the circulation, but 
occasionally is a cardiac paralyzant, and may cause 
death by cardiac arrest while yet respirations are 
fully maintained. 
The most remarkable surgical performance shown 
in the whole Congress was that of Prof. Gluck, 
of Berlin, who presented several patients whose 
knee and elbow he had excised, and thereafter sub- 
stituted ivory joints instead. The patient upon 
whom this singular essay had been longest under 
trial was one upon whom the operation dated three 
months back. In two instances the professor had 
succeeded in giving the patients moderately movable 
joints, but in no case were the wounds fully healed 
and free from suppuration. And in one from whom 
he had subsequently removed one of his ivory 
joints after it had been worn for some time, on 
account of local trouble to which it gave rise, the 
ivory was seen to be partly eroded, as though begin- 
ning to be absorbed. This surgical experiment was 
viewed with decided scepticism as to its ultimate suc- 
cess by the majority of those who saw it, while, never- 
theless, they appreciated the cleverness of the feat. 
