107 
v closer study of the metabolism in this direction might throw light 
n the process of tion; for mere determination of carbonic acid - 
without considering em conditions cannot naturally explain it. 
Finally, I must point to the constitution of citrie acid as having an 
important bearing on the theory of these fermentative processes. It is 
clear that it cannot be regarded as a direct product of sugar-oxidation. 
[ Published June 22.] 
Tt is an interesting coincidence that the Sugar-cane for Februar 
discusses (pp. 67-70) the occurrence of “ Citric Acid in Cane Juice." 
The acid appears r some circums appea in 
the process of sugar manufacture grr give (ee is the most important 
portion of the account of the matte . 69) in a letter from 
p 
Mr. Edmund C. Shorey, of Kohala Hikoia Islands). 
“An examination of the organic matter showed that - keen 
constituent was citric acid, and this combined with lime caleium 
citrate formed the body of the seale. 1 have by dione iin scale 
with sulphurie acid, forming sulphate of lime and setting free the citric 
acid, filtering and vbi ciens A aere quite large ery: stals of citric acid. 
ere are several other organie acids present t, the) nature of which I have 
not yet amenities, but the itea acid predominates and is the one that 
gives most trouble “owing to the property of calcium citrate being more 
soluble in cold than in hot water, and consequently of being precipi- 
tated from a boiling solution. Unless most of the calcium “citrate is 
r. 
shows itself as a fine grain or cloud, much like “ false enin" i in appear- 
ance, and having the same effect in ari pe RA preventing the 
purging of molasses. A strike of No. 2, which cannot be d 
the presence of calcium citrate, will generally dry pone cold, enough of 
MAL AULA P VY ake 
vim the pum “of ‘ime will meatier to I gena as a fine white 
powder. 
Citric acid also makes its appearance in the manufacture of Sorghum 
cn (pp. 69, 70). 
r. Oma Carr, of the United States Department of Agriculture, has 
reali examined a scale or deposit from the Sorghum sugar house at 
Medicine Lodge. " é 
* Except in the Prepestines of lime and magnesia aui is not unlike 
the scale I have been considering, and the similarity extends to the 
organie matter, Mr. Carr havi ng found that in this case citrie acid was 
the predominant organic acid. 
“I do not consider citric acid a normal constituent of cane juice as 
ordinarily found in Hawaii, and whether in this case its presence is due 
to the extremely dry weather or to the fact that the cane is green I 
cannot tell. An examination of green cane juice during a wet season~ 
would throw some light on the question. 
'There are two possi ible explanations of this interesting observation. 
One is, that the citric acid ferment, which is probably ubiquitous, may 
