30 
MEMOIR OP BARON HALLER. 
of motion. Comparative anatomy likewise informs 
us that this membrane is simply a true cover for 
the brain, for in some animals, as in the tortoise, it 
is found of a cartilaginous consistence.” 
There were other points of controversy in which 
Haller found himself early engaged. One of the 
most important of these regarded the respiration in 
man and the mammalia, and especially the instru- 
mentality by which this vital function is effected. 
M. Hamberger, an eminent professor at Jena, had in 
1727 published an account of the mechanism of respi- 
ration. According to his view, which was in unison 
with the prevailing and established notions, there 
was a permanent collection of air within the chest, 
between the ribs and lungs, as occurs in birds ; and 
this air exerted an influence in compressing the 
lungs, which compression was, moreover, assisted 
by the action of the internal intercostal muscles. 
These opinions had, about the same time, been 
advocated also by M. Bayle of Toulouse. In re- 
ference to them, we shall allow Haller to speak for 
himself : — “ The commentaries which in 1739 I 
commenced to give upon the Institutes of my 
illustrious master Boerhaave, led me to the subject 
of the mechanism of respiration, the thoracic air, 
and the use of the intercostal muscles. I could not 
agree with the views of M. Hamberger, with whom 
I was on terms of intimacy. Accordingly, I spoke 
of him with commendation, and endeavoured to 
treat him with politeness while commenting on his 
hypothesis; I cherished every feeling of delicacy 
