7 
102 Memoir on the Saccharine. Diabetes. 
ture of 18° (64° Fahr.), and to remark attentively all the 
phenomena produced by this mixture. Fermentation soon 
began: it was brisk at first, but it soon. decreased ; and in 
two days it ended. The liquor had nevertheless. a very 
strong vinous smell; but far from being alcoholic, it was, 
on the contrary, very saccharine, aud deposited upon, eva- 
poration, in the form of crystals, almost all the, matier em- 
ployed, deprived of the fermenting faculty. 
Although convinced by these veanlts that manna copiained 
only a very small quantity of sugar, we ought nevertheless 
to compare it in all its properties with this substance, in 
order to place the fact beyond a doubt, and thus to discover 
all the characters peculiar to the particular principle of which 
it, appeared. almost entirely formed: we therefore tried its 
action on spirit’ of wine, which did not attack. the saccha-. 
rine principle, and upon the nitric acid, which did not con- 
vert any portion of that principle. into mucous acid, . 
The former of these reagents, at the temperature of 60° 
(140° Fahr.), dissolved so, greata quantity of manna, that, 
upon cooling, the liquor was a mass composed of a crowd 
of crystalliné heaps, every crystal in each heap springing 
from a common centre. The second reagent produced, after 
a long ebullition, so, great a deposit of mucous,acid, that 
it was almost half the weight of the manna employed. 
Here therefore, there are two characters which are striking 
ly different; sugar properly so called, and the particular prin+ 
ciple of manna. 
New researches will doubtless present many other diffe- 
rences more or Jess prominent ; but those above related being 
sufficient to occasion these bodies to be regarded as very di- 
stinct from each other, we did not think it necessary to 
enter more deeply into the subject. 
It follows from hence, that it would be always easy to 
recognize and separate manna, or rather the peculiar prin- 
ciple of manna, whatever may be the substances with which 
it is mixed. It is only necessary to treat with warm alcohol 
the matter which contains this peculiar principle of manna, 
and it will be almost entirely precipitated upon cooling. In 
truth, there are other yegetable substances which possess 
this 
