ON DEXTRINE AND DIASTASE. 
271 
and that the sum of the weights of the sugar, and gum, or 
dextrine, equals the weight of the amidone. 
11th. That in the preparation of beer, it is important to ef- 
fect the entire transformation of the amidone, into dextrine 
and sugar; so that the transparency of the fluid will not be 
troubled afterwards, which would be the case if amidone was 
present. 
12th. That in the first developement of certain plants, the 
diastase is placed precisely at the point where the fecula ought 
to be rendered assimilable so as to transform the insoluble 
fecula into two soluble substances, capable of being absorbed 
by the plant. 
13th. That diastase only transforms amidone, as it is with- 
out action on gum, (properly so called,) inulin, albumen, gluten, 
teguments, and lignin. 
14th. That during the process of germination, the propor- 
tion of the diastase increases with the developement of the 
gemmule. 
15th. That amidone forms about .995 of fecula, while the 
teguments deprived of all amidone make up the remainder. 
Finally, that diastase has become an importantagent in the 
chemical analysis of fecula, and forms an easy means of making 
commercial dextrine. 
M. Guerin says, that he followed M. Chevreul in nam- 
ing the principles which he has described,* that is to say, 
amidine to the portion of fecula soluble in cold water; tegu- 
menlary amidin to the part insoluble in either cold, or boil- 
ing water; and soluble amidin, to prevent all confusion, to 
the part which is held in solution by amidine, and which is 
identical in chemical composition with tegumentary amidin. 
The amidine of Guerin, is made by boiling fecula in a 
large quantity of water for a short time, allowing it to stand 
until the teguments precipitate, filtering, and evaporating the 
filtered liquor to a syrupy consistence, when a precipitate 
gradually forms, which is to be separated by a cloth, and the 
*Annales de Chim. et de Physique, tome Ivi. 
