METAMORPHOSIS OF SACCHARINE MATTER, 
103 
lactic acid (C 6 H 6 O s ). We also find that sugar is not sus- 
ceptible of oxidation except under the influence of strong 
chemical reagents. Chemical analogy, therefore, would lead 
us to look upon the secondary action of oxygen as the more 
probable process of physiological destruction ; especially 
when we take into consideration, that nowhere do we meet 
with such a constant series of molecular changes taking 
place as amongst the azotized constituents of a living animal. 
In the above-mentioned experiment of injecting fibrinated 
and defibrinated blood through an artificially inflated lung, 
when the blood is capable of undergoing the molecular 
changes of assimilation on contact with oxygen as in the 
living animal, the sugar in great part disappears, but so 
soon as the fibrine is separated by spontaneous coagulation, 
and the blood has thus lost its vital characteristics, oxygen 
is no longer capable of exerting any metamorphosing influ- 
ence on its saccharine ingredients. 
If the molecular changes occurring during the decomposi- 
tion of an azotized substance be capable of converting sugar 
into lactic acid, why should not the molecular changes 
occurring during the building-up or elaboration of this same 
nitrogenized compound effect the same ? Indeed, we have 
seen that the process of destruction is carried on to a certain 
extent in the systemic capillaries, and more especially in those 
of the chylo-poietic viscera, where the molecular changes of 
nutrition are also correspondingly carried on with greater 
activity than elsewhere. So that analogy and experiment 
would tend to show that the physiological destruction of 
sugar is owing to a process similar to fermentation induced 
by the molecular changes occurring in the nitrogenized con- 
stituents of the animal during life ; and, in accordance with 
this, we find lactic acid present in the system, and largely 
separated from arterial blood by the muscular tissue, and the 
secerning follicles of the stomach. 
As regards the lactic acid fermentation, it is well known 
that the presence of an alkali favours, whilst that of an acid 
retards the process. In two experiments on animals, the 
author injected carbonate of soda and phosphoric acid into 
the circulating current, and observed in the case of the latter 
that sugar immediately accumulated in the blood. 
The preceding observations refer more especially to the 
changes that take place in the saccharine ingredient of the 
blood during life ; and the author next proceeds to notice 
some interesting phenomena observable during the decom- 
position, and even the spontaneous coagulation of blood con- 
taining sugar. 
