June 1, 1899] 
NATURE 
109 
lationship of external surroundings to the spread of 
tubercular disease. The author pointed out the un- 
satisfactory nature of statistics upon this subject, owing 
to the complexity of apparently simple factors. Constant 
attendance upon phthisical patients in badly ventilated 
rooms, and certain occupations giving rise to irritation of 
respiratory tract from dust, metallic or otherwise, were 
however, according to the lecturer, potent factors in the 
spread of tuberculosis. Papers followed upon tuber- 
cular disease among various employés, notably knife and 
sword makers, bookbinders, compositors, and cigar 
makers. 
Section II.—Aetiology.—This Section was opened by 
Prof. Fliigge (Breslau), who read a well-appreciated 
paper upon the relation of the tubercle bacillus to tuber- 
culosis. Recent work has not in this connection modified 
to any extent the dicta originally enunciated by Koch. 
The tubercle bacillus is the immediate cause of tuber- 
culosis, and arises in practically all cases from a 
tuberculous animal. Its parasitic nature is obligatory, 
g.e. except in the case of artificial cultures the bacillus 
cannot develop outside the animal organism. By 
means of artificial cultures it is possible to modify the 
tubercle bacillus in certain ways, notably with regard 
to its morphological character, and its virulence. Prof. 
C. Frankel (Halle) discoursed eloquently upon the 
nature and #odus operandi of tubercular infection. He 
pointed out that outside the animal body tubercle bacilli 
die in from six to seven months, the important factors in 
killing them being light, and the fact that they lose 
their water by evaporation, and with it their life. As 
a result of this it is, as a rule, only the immediate 
neighbourhood of the patient, from 1 to 1} metre, that is 
infective.. Infection usually takes place through the in- 
fected person inhaling freshand moist tubercle bacilli which 
(“infected drops”) have been ejected usually during a 
coughing fit, also by the inhalation of dust contaminated 
with dried sputum. He further pointed out that man 
was relatively unsusceptible to tubercular infection, and 
that, as a rule, it was only by repeated and continued 
inhalation, &c., of tubercle bacilli that infection occurred. 
A subject of great interest to physicians was considered 
at some length by Prof. Pfeiffer (Berlin), viz. “mixed 
infection.” Consumption, as we know it, is rarely due 
simply to the tubercle bacillus, but to the superadded 
action of other infective organisms. As many as twenty- 
four different varieties of bacilli have been obtained from 
the sputum. of a phthisical patient. An important 
practical point brought out by the lecturer was that 
cases of mixed infection ought to be recognised in con- 
sumptive hospitals, and isolated, as they may bea source 
of danger to phthisical patients ; that is, these latter may 
get a mixed infection superadded to their other troubles. 
Prof. Loffler read ashort paper upon heredity, immunity 
and disposition in their relation to tuberculosis. Here- 
ditary tuberculosis in the sense, for instance, of congenital 
syphilis, is unknown. In this disease hereditary influences 
probably play a relatively small part as such. Tuber- 
culosis occurs in members of the same family, mostly 
because by living together the members infect each 
other. Prof. Loffler quoted one family as an instance 
of this. The father and mother, two daughters and 
seven sons, all died of phthisis. The family consisted 
of fifty-eight other members, not one of whom was 
tuberculous. The infection was entirely confined to the 
members of the family living together. The lecturer 
emphasised the fact that no natural immunity to tuber- 
culosis exists. Dr. von Zander gave some aetiological 
Statistics of tuberculosis. Out of 312 cases investigated, 
116 were communicated from man to man; amongst 
these infection between sisters occurred the most 
often. ' 
Section III.—Prophylaxis.—Dr. Roth (Potsdam) dis- 
cussed certain rules for the prevention of tubercular infec- 
NO. 1544, VOL. 60] 
tion. These mostly consisted of measures directed to the 
disposal of the sputum, and the use of a cloth in front of the 
mouth during coughing fits, to limit the area of “infective 
drop ” dispersion. Prof. vy. Leube (Wurzburg) considered 
the prophylactive methods against tuberculosis in 
hospitals. If measures such as those mentioned above 
are thoroughly carried out, tubercular patients need not 
be isolated from the general hospital inmates. Care 
should be taken by attendants and nurses especially in 
dusting rooms, when it would be advisable for them to 
have their mouth and nose protected by a mask. 
All members of the Congress listened most attentively 
to a short paper, by Prof. Virchow, upon the prevention 
of tuberculosis in so far as concerns food. Prof. Virchow 
considered four articles of diet: (1) beef, (2) pork, (3) 
poultry, (4) milk. Of these he regarded milk as far the 
most important. He advised a more careful and 
systematic exclusion (under central control) of tubercular 
meat and cattle, and the rejection of milk from all cows 
which reacted to the tuberculin list. Even these measures 
the author described as palliative, the only curative 
measure being the killing of all animals that reacted to 
the tubercular list. In this connection, Dr. Schumburg 
(Hannover) gave the result of his researches as to whether 
ordinary butcher’s meat contained tubercle bacilli. The 
result of twenty-four inoculations (intra-peritoneal) of 
guinea-pigs with the juice of twelve different meat samples, 
was that two animals died of purulent peritonitis, two 
greatly diminished in weight, the remaining twenty 
remained well. Dr. Baer (Berlin) discussed the much- 
vexed question of alcohol and tuberculosis. He concludes, 
upon apparently very insufficient grounds, that alcohol 
in the consumptive sanatoria should only be used as 
medicine under the most urgent circumstances. Dr. 
Ritter read a paper upon the protection of children from 
tuberculosis. An interesting communication upon the 
diminution in the total death-rate from consumption due 
to modern methods of treatment was made by Dr. Julius 
Lehmann (Copenhagen). Dr. Kuno Obermiiller discussed 
some interesting investigations upon the presence of 
the tubercle bacillus in ordinary market milk and butter. 
He centrifugalised the milk, and injected less than °5 cc. 
of the sediment into the peritoneal cavity of guinea- 
pigs. The milk was taken from a dairy which supplies 
Berlin with 80,000 litres daily. The result was that 30 per 
cent. of the injected animals died in from eleven to thirteen 
weeks of tuberculosis. The milk used was the best and 
most costly infant milk. According to the author, Berlin 
butter is also largely infected with virulent tubercle 
bacilli, which are quite distinct from the so-called butter 
bacillus. Dr. Hambleton, President of the Polytechnic 
Physical Development Society, was the author of a com- 
munication on the prevention of pulmonary tuberculosis. 
One of the most potent factors to this end is, according 
to the author, chest development, and he took this oppor- 
tunity of bringing before the notice of the Congress the 
work of the Society in this direction. This method had, 
according to the author, been most successful in pre- 
venting and even arresting tuberculosis among the 
employés of trades having an injurious effect upon the 
respiratory organs. F, W. TUNNICLIFFE: 
THE JUBILEE OF SIR’ GEORGE GABRIELE 
STOKES. 
A(uane celebrations in connection with the jubilee of 
Sir George Gabriel Stokes, who has occupied the 
Lucasian Chair of Mathematics at Cambridge University 
since 1849, begin this afternoon (Thursday) with the 
delivery by Prof. Cornu, of the Ecole Polytechnique, 
Paris, of the Rede Lecture. Prof. Cornu has chosen 
| as his subject, “The Wave Theory of Light and its 
Influence on Moder Physics.” 
