AN ESSAY ON FAT AND MUSCLE. 
671 
production of fat. Many physiologists conceive that the secretion 
of bile is by no means the sole function performed by the liver, 
and look upon it as a supplementary organ of the lungs, assisting 
that organ in the depuration of the blood, and, like it, eliminating 
from the blood its superfluous hydrogen and carbon. The same 
will apply also to the spleen, its functions being, we believe, also 
subsidiary to the lungs as a purifier of the blood. It is a very 
common occurrence to find stall-fed animals with diseased livers, 
and yet this does not interfere with the power of accumulating fat ; 
on the contrary, if our theory be correct, it must materially assist 
in accelerating this process. We have witnessed the same in the 
livers of horses in many instances. The animals will continue to 
do fair ordinary work in either coaching or posting, and always 
look healthy, when, should they be attacked with some prevailing 
epidemic or a severe catarrhal affection, the veterinary practitioner, 
and especially the young one, will be surprised to find that the re- 
medies that, in similar cases, had proved successful, may fail here ; 
and he does not get at the truth until a post-mortem examination 
reveals to him that there are extensive lesions of the structure of 
the liver, it having the same appearance as if it had been boiled. 
Professor Playfair was the first who directed the public attention 
to the fact just related, that an animal having small offal was more 
disposed to fatten, and to come quicker to maturity, than an animal 
with large lungs, liver, &c. We believe we are correct in stating 
that this discovery was never brought before the public until he 
delivered his two lectures before the Royal Agricultural Society 
on December 27, 1842 ; and it was in consequence of some in- 
quiries which we made to ascertain the truth of the Professor’s 
statement, that we also became acquainted with another singular 
and important fact , — that in proportion as an animal fattened, so 
in proportion did the organs which are chiefly connected with 
nutrition become diminished in size . This fact we shall find to 
be intimately connected with the breeding, rearing, and feeding of 
animals. We draw our conclusions from examining a great 
number of stall-fed animals, chiefly of the Devon breed, averaging 
from 5 cwt. to 9 cwt. of meat. We have seen them slaughtered at 
all stages of feeding, from the comparatively lean to the fatted ox ; 
and the result of our observations has been, that in proportion as 
the fattening process went on, the lungs, stomachs, intestines, liver, 
&c., were reducing in size. It has already been stated that a 
constant change of particles is going on in the tissues of the living 
body ; and it has been computed by physiologists that the human 
body, including the skeleton, is taken down and rebuilt about every 
seven years : so that we may safely say that it is being taken down 
and rebuilt at the same time ; and that the processes of destruction 
