276 
ORIGINAL COMMUNICATIONS. 
U m teguments, interior tissue, { 
Biot & Persoz, teguments, $ substance aria ; dextrine. 
G ' £ logous to inulm, 
Guerin, {imiaTn, ntary soluble amidin > a midine. 
Payen & Persoz, teguments, amidone 
. >v_ 
\ 
substance analogous dextrine or gum. 
to inulin. 
By scrutinizing the foregoing remarks, we will observe a 
great confusion of names, indeed almost as many sets of 
names as we have experimenters on the subject. There is 
evidently an analogy between some of the results, and the pro- 
bability is, (hat the amidine and soluble amidin of Guerin, 
taken together, constitute the amidone of Payen and Persoz, as 
both amidine and amidone, color blue with iodine, and both 
are obtained without the use of any other agent but water 
and temperature. The matter of amidone which causes it to 
swell, may be a tissue-like substance, which, when separated 
by ebullition, etc., constitutes the soluble amidin held in solu- 
tion by amidine of Guerin. 
I think we may safely differ from Raspail, who considers 
the dextrine by sulphuric acid of Biot, to be the soluble sub- 
stance of fecula. Dextrine when obtained in that way, as well 
as by diastase, gives a vinous red or purple hue with iodine, 
while the subtances which are derived directly from fecula by 
water give a sky blue. 
Raspail says, that all, save the teguments of fecula, is solu- 
ble substance, an assertion which is not borne out by fact, for 
we find that amidone is not soluble. 
He also asserts, that diastase is soluble gluten, or gluten held 
in solution by acetic acid. Wishing to test the truth of this 
assertion, some gluten was prepared and dissolved in acetic 
acid. This, then, should possess the power of diastase. Two 
drams of fecula were mixed with two ounces of water, and as 
much solution of gluten as equalled two or three grains of 
the undissolved substance was introduced along with it, and 
