Dec. 9, 1869] 
NATURE 
159 
The whole staff directs the laboratory ; and over and above these 
are the two professors of physiological and agricultural chemistry, 
who conduct their own laboratories. 
In Physics, Professor Weber and his assistants, Professors 
Listing and Kohlrausch, conduct an excellent physical laboratory, 
and lecture on the several branches of physics—systematic phy- 
sics, optics, electricity, &c., light and heat, meteorology. Pro- 
fessor Ulrich treats of hydrostatics and hydraulics. 
In Natural History, Professor Keferstein lectures on compara- 
tive anatomy, and performs zootomical demonstrations in the 
Zoological Museum during eight hours weekly to the students ; 
for four hours weekly the Museum is open to the public, when 
the same Professor is present to conduct demonstrations. Two 
professors lecture on Botany (each six hours weekly), and com- 
bine with their lectures excursions and demonstrations in the 
Botanical Garden ; there is also a third assistant professor. Pro- 
fessors Sartorius Von Waltershausen and Von Seebach lecture 
each four or five hours weekly on Mineralogy and Geology, and 
conduct practical demonstrations in the Museums. 
In Heidelberg, as in Berlin and Géttingen, and in 
some respects even in a more perfect measure, large 
provision is made for the study of physical science. 
The Physical Laboratory, conducted by Professor Kirch- 
hoff, is very successful. Once weekly Professor Kirchhoff 
lectures, with experiments, on a given subject; in the 
following week each student in the laboratory goes 
through the experiments for himself, and in this consists 
the essence of the course. Students can also pro- 
secute independent research for several days in the 
week. 
The Chemical School of Heidelberg has always been a 
celebrated one, and since the appointment of Bunsen to 
the university its renown has greatly increased. In no 
other European laboratory, with the single exception of 
that of Liebig at Giessen, have so many promising scien- 
tific chemists been trained, and this has been wholly due 
to the untiring interest shown in each student by the 
illustrious Professor, who, devoted heart and soul to his 
science, imparts to his students a portion of that interest 
in, and zeal for, original investigation, which are the real 
marks of ascientific spirit. Many of the chemical students 
at Heidelberg come, as with us, to study the science for 
the sake of its subsequent applications to manufactures, 
medicine, or pharmacy (for all the German druggists and 
pharmaceutical chemists are wisely compelled to attend a 
regular university course), but many, probably a large frac- 
tion of the number, study the science for its own sake, 
most of these students intending to qualify themselves 
for the higher posts of scientific instruction in various 
countries. Amongst the companions of those who studied 
at Heidelberg with the writer were men who are now 
making rising reputations in most of the German univer- 
sities, or in the various institutions of France, Russia, 
Portugal, Great Britain, and America. 
The Physiological Laboratory, conducted by the cele- 
brated philosopher Helmholtz, is a novel and important 
feature in the Science Department in Heidelberg. A 
handsome and spacious building has recently been erected 
for the use of the Professors of Physics and Physiology. 
This embraces lecture-rooms, laboratories, rooms for 
apparatus and instruments, and for conducting special 
scientific investigations, besides dwelling-houses for the 
professors and their families. 
In another article I propose to inquire more closely 
into the cost of establishing and working the Science 
Department of the German universities. 
HENRY E, ROSCOE 
A POINT IN MUSCULAR PHYSICS 
(Sau Physiologists abound in statements touching 
the correlation of forces in living things, and are 
very fond of repeating the old parallel between a muscle 
and a steam-engine. We have no desire to deny the 
aptness of the illustration, but it is as well to bear in mind 
that, in actual point of fact, the exact correlation of heat 
and mechanical force has not, as far as muscle is con- 
cerned, yet been made fully out. The point of failure 
is this—suppose we have two muscles: let one muscle 
when it contracts have to pull against a weight and so pro- 
duce a decided mechanical effect ; let the other muscle 
have no such weight to pull against, and so in contracting 
produce no mechanical effect (the trifling weight of the 
muscle itself we may disregard). According to the 
doctrine of the correlation of forces, the heat ‘given out in 
the first case ought to be less than that given out in the 
second, by reason of the total force produced by the com- 
bustion of the muscle going out partly as mechanical force 
instead of wholly as heat. We suppose of course that ex- 
actly same amount of contraction takes place in both 
cases, and indeed that the muscles are perfectly identical 
in circumstances, except so far as their load is concerned. 
Heidenhain some few years ago, however, found out that 
there was, strange to say, more heat given out in the first 
case. He also discovered the reason of it, which is that 
when a muscle is put on the stretch, as, for instance, when 
a muscle has in contracting to pull against a weight, a// 
the chemical changes in the muscle are augmented, and 
that roughly in proportion to the amount of strain. 
This observation by Heidenhain seems to us one of 
very far-reaching and often-recurring importance, though 
apparently it has hardly as yet gained the attention it 
deserves. At all events it put a stop for a while to any 
satisfactory settlement of the question we are considering. 
Quite recently, however, Fick has devised an experiment 
which seemed to him to avoid the difficulty that had 
discomfited Heidenhain. The gist of it is simply this. He 
has two muscles in every way treated alike except in the 
following point. One muscle he allows to pull a weight 
up by the force of its contraction, and then lets the weight, 
when the contraction has passed over, pull the muscle 
down again. The other muscle pulls up the same weight 
in the same way, but at the moment that the contraction 
is at its maximum the weight is slipped off. The muscle 
then by virtue of its elasticity returns to the length natural 
to it when unloaded ; directly it has reached this point 
the weight is slipped on again, and the muscle is again 
ready for a contraction. 
It is obvious that in the first case the muscle does no 
actual work at all; after the contraction the weight 
undoes what the contraction did. In the second case, on 
the other hand, the weight is lifted up to a certain point 
and left there ; real work is done, 
Such being the case, the temperature of the first muscle 
ought to rise higher than the second; and when each 
muscle has been made to contract a good many times 
this rise ought to be appreciable. Fick finds in fact 
that it is so. And so we seem here to have what we 
desired; for both muscles during contraction are subject 
to the same strain; and hence Heidenhain’s objection is 
obviated. 
