648 
in the course prepared for them by the 
earlier investigations. In several compre- 
hensive and valuable papers on the his- 
tology and physiology of the intestine the 
inadequacy of osmotic forces to accomplish 
the work of absorption under many condi- 
tions is experimentally shown, the methods 
of the newer physical chemistry being 
drawn upon to yield results in a new field. 
Simple physical forces were supplemented 
by ‘physiological’ processes and the seat of 
these was assigned to the living epithelial 
cells. The researches on the formation of 
lymph which have appeared from the Bres- 
lau institute in recent years have opened 
up a broad field of inquiry that, together 
with the problems of absorption and transu- 
dation, is interesting physiologists to-day 
as perhaps few otherthemes are. Nowhere 
in Heidenhain’s hypotheses have simple 
physical factors been excluded ; but the dif- 
ficulty or inadequacy of the latter in ac- 
counting for all the facts known is made 
~ipparent. And remembering the many dif- 
ferences of opinion that have arisen, let me 
quote the words of Professor Michael Fos- 
ter: ‘In the controversy thus arisen, the 
last word has, perhaps, not yet been said, 
but whether we tend at present to side 
with Heidenhain, who has continued into 
the past thirteen years the brilliant labours 
which were, perhaps, the distinguishing fea- 
tures of physiological progress in preced- 
ing periods * * * or whether we are 
inclined to join those who hold different 
views, we may all agree in saying that we 
have, in 1897, distinctly clearer ideas of why 
secretion gathers in an alveolus or lymph 
in a lymph space than we had in 1884.’* 
The preceding must suffice in this place 
to indicate some of the advances which 
physiology owesto Heidenhain. If to these 
is added the mention of his researches on 
* Address to the Physiological Section, British As- 
sociation for the Advancement of Science, Toronto, 
1897. 
SCIENCE. 
[N. 8. Vou. VI. No. 148. 
the tonic contractions of sphincter muscles, 
on the heart and the nervous system, on 
hypnotism, etc., one cannot fail to be im- 
pressed by the broadness ofthe man. Asa 
scientific writer his style is interesting and 
convincingly logical. His two monographs 
in defence of vivisection * have been widely 
circulated. As a teacher Heidenhain en- 
joyed unusual success. His lectures were 
remarkable for the lucid treatment of every 
department of physiology and _ histology, 
and few physiologists, I venture to add, 
were so liberal in their demonstrations. 
With every chapter at once made historical 
as well as critical, and giving evidence of a 
very wide acquaintance at first hands with 
the literature of the subject, these lectures 
would form an admirable text-book with 
which few of those now used on the Conti- 
tinent could favorably compare. The mod- 
est equipment of the old laboratory formed: 
a striking contrast to the splendid results it 
yielded at the hands of a master. 
Heidenhain’s home life was charming 
and the reception within the family circle: 
always cordial. To one associated with 
him in his work, nothing was more impress- 
ive than the man’s intense devotion to his. 
science. The indifferent student could ex- 
pect little sympathy from Heidenhain ; but. 
no attention was spared, no effort too great 
in behalf of the individuals who won favor 
in the Breslau institute. Logical argu- 
ment and unbiased observation character- 
ized Heidenhain’s presence in the labora- 
tory. His thoughts continually wandered 
into the realm of unanswered problems, 
and more than once in recent years did 
he express the regret that the days still 
left must be brief, at most, for the tasks 
awaiting completion. These fruitful labors. 
have, indeed, been ended too soon. 
LAFAYETTE B, MENDEL. 
YALE UNIVERSITY. 
* Die Vivisection im Dienste der Heilkunde,’ 1879, 
and ‘Die Vivisection,’ 1884. 
