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DE. PAYY OX SrOAE rOE:MATIOX IX THE LmiE. 
the presence of this principle might be due to some jpost-^mortem change. Acting upon 
this idea, I resolved to see if I could not alight upon the organ in the state actually 
belonging to life, by placing it in a condition at the instant of death that would prevent 
any subsequent production of sugar. 
The researches of Beexaed ha'sing disclosed the existence of a material in the liver 
which passes with great rapidity into sugar under the influence of ferments, I looked 
for an agent that might possess the power of preventing this transformation, without 
destroying the material or its product. Saliva is an exceedingly energetic ferment 
towards this substance, but I found that it ceased to exert any catalj-tic effect in the 
presence of an alkali. I therefore injected a strong solution of potash into the portal 
vein instantaneously after the destruction of life, with the view of preserving the liver 
in its natural state. After this operation, I have failed to detect any, or more than a 
mere trace of sugar in the substance of the organ; and it has been proved, by after- 
wards submitting a liver in which saccharine matter has existed, to a precisely similar 
process, that the injection has no efiect towards leading to a decomposition of this prin- 
ciple. A saccharine liver injected with potash gives as copious a reaction as if the 
injection had not been practised. 
Acids, like alkalies, check the action of ferments on this substance belonging to the 
liver, and a strong solution of citric acid injected into the portal vein has been observed 
to be followed by a similar effect to the injection of potash. 
Although I believe that these experiments may be relied on as affording accimate 
information regarding the physiological state of the liver, yet a feeling of hesitation 
might possibly arise in accepting the results derived from the employment of a caustic 
alkali, when the subsequent recognition of an organic substance like sugar is concerned. 
There are other means, however, that enable us to display the condition of the liver 
belonging to life. The mere alteration of temperature is sufiicient to effect the object 
that is deshed. Processes of the nature of fermentation are checked by cold ; and as 
the formation of sugar in the liver is of this character, the rapid abstraction of heat 
instantaneously after the destruction of life prevents any post-mortem change taking 
place, and presents us with the organ in a natural or physiological state. 
The experiment showing the effect of reduction of temperature is thus performed. 
An animal is killed as quickly as possible by pithing the medulla oblongata. The abdo- 
men is instantly opened by a free incision through its parietes, and a piece of the liver 
sliced off and plunged into a freezing mixture of ice and salt, which has stood sufii- 
ciently long to have become liquefled. If the ice and salt are used immediately after 
being mixed, and whilst still in a solid state, their cooling effects are not nearly so 
intense, and not sufficiently so for our purpose. The piece of liver in the course of a 
few minutes is frozen quite hard. It is taken out, cut up into thin slices, pounded to a 
pulp in a mortar, and placed, a little at a time, in a rather small quantity of water, which 
is kept thoroughly boiling during the process. The cold has merely checked the action 
of the ferment existing in the liver. The materials are there in an imdestroyed state. 
