DE. TAYY ON STJGAE EOEMATION IN THE LIVEE. 
601 
and a production of sugar takes place on the temperature being raised to a moderate 
extent. The object, therefore, is to apply the heat rapidly, so as to coagulate the albu- 
minous principles and thus destroy the ferment. The decoction that is obtained gives 
none, or at the most the merest trace of reaction. It abounds in the sugar-forming 
substance, and on being treated with a little saliva and exposed to a moderate heat, a 
transformation is with an astonishing rapidity effected. The remainder of the liver that 
has been left in the animal is now submitted to the ordinary process of preparation, and 
tested, to show that it gives the usual reaction that was formerly thought to belong to it 
during life. 
The rabbit is a more favourable animal for this experiment than the dog, because, on 
account of its size and the thinness of its abdominal parietes, the liver can be more 
quickly reached and a piece of it sliced off. Again, the liver of the rabbit is not so thick 
as that of the dog, and thus is more rapidly acted on throughout by the freezing mix- 
tui'e. I have often, in the case of the dog, found the moderately thick outside parings 
of a piece of frozen liver free, or almost completely free, from sugar, whilst the centre 
has given a tolerable saccharine reaction. The centre of a thick piece of liver may be 
found, even after immersion for some minutes, in a soft or unfrozen state ; and when 
the abstraction of heat is only gradual, time is given for the production of a certain 
amount of sugar. 
Whether the animal, either rabbit or dog, is at a period of digestion or not, makes 
no difference, that I have perceived, in the result. Usually my experiment has been 
made a few hours after food has been taken. A piece of healthy frozen liver that is 
free from sugar, on being raised for a few minutes to a temperatru’e of 90° or 100°, 
gives a most copious saccharine reaction. A piece of saccharine liver plunged into a 
freezing mixture loses none of its saccharine qualities. 
The result produced by boiling water on the liver is similar to that of a freezing 
mixture. It coagulates or destroys the materials capable of acting as ferments, and so 
prevents the ordinary post-inortem transformation from occurring. Its action, perhaps, 
is not quite so perfect as that of freezing, but still, especially with the liver of the rabbit, 
specimens are easily obtained yielding only the faintest indication of sugar. On testing 
tlie decoction, there is no change on boiling with the blue liquid, but after some time 
a few particles of red precipitate may subside. The animal is suddenly killed, and a 
piece of the liver as rapidly as is possible removed and thrown into a large quantity of 
boiling water. It need not remain more than two or three minutes. Pounded in a 
mortar with water and boiled, a liquid is furnished on filtration for testing. 
It has been noticed by Beexaed, that after division of the spinal cord just below the 
phrenic nerves, the liver is found free from sugar upon being ordinarily examined at the 
period of death, whilst it becomes strongly saccharine afterwards. Various suggestions 
have been made in explanation of this phenomenon. The fact itself is a most striking 
one, and has frequently been corroborated in my laboratory. It fully agrees with the 
experiments I have been mentioning, and receives from them, I consider, a satisfactory 
MDCCCLX. 4 K 
