SACCHARINE AND ASTRINGENT EXUDATIONS OF GREY GuM. 183. 
reducing an alkaline copper soluti lily than the ordinary 
white Eucalyptus manna from JF. viminalis, etc. The only 
mention that I can find of manna from this tree, is, that the Rev, 
Dr. Woolls noticed that occasionally melitose manna dropped 
from Z. punctata.! 
Previous work on Melitose and Raffinose. 
Attention was called to the peculiar saccharine substance 
obtained from Eucalyptus viminalis, and known as “manna,” by 
Thomson’ early in this century, and by Virey’® in 1832. In 1843 
Johnston‘ chemically examined this manna, and distinguished it 
from the Ornus-manna or manna of commerce. In 1855 it was 
further examined by Berthelot,’ who named the sugar it contained 
“melitose,” and who found that its aqueous solution was dextro- 
rotatory, and that when heated with dilute sulphuric acid it was 
altered into two sugars, one of which was fermentable, while the 
other was not; to this latter he gave the name of “eucalyn” with 
the formula C,H,,0, It was not until 1884 that the sugar 
melitose (raffinose) was found existing in any other substance 
except the manna from the Eucalypts of Australia, although 
Loiseau® had discovered a sugar in 1876 in molasses to which he 
gave the name of “raffinose.” Melitose (raffinose) was then found 
by H. Ritthausen’ to exist in the residues from pressed cotton 
seeds. In 1885 B. Tollens® described a sugar which he had 
obtained from molasses, and then indicates that raffinose and 
tmelitose may be identical, although he was not satisfied on the 
point at that time, but expresses a doubt whether his sugar and 
the raffinose prepared by Loiseau from molasses were identical. 
In 1885 H. Ritthausen with others? again further describe the 
Sugar from cotton-seed cake and prove it identical with “plus- 
Sugar” from molasses, and also with Béhm’s “gossypore,”” and 
1 Eucaly yptographia, art. E. viminalis. 
2 Organic Chemistry, Vegetables, 642. 3 Journ. de dame [2] 18, 705. 
* Mem. of the Chem. Soc. 1., 159. 5 Compt. Rend. xx1., 392. 
6 Compt. Rend. pexxr:; 1058. 7 Journ. Prakt. Chem. it xxIx., 351. 
8 Ber. 1885, p. 26. 9 Bied. Centr. xrv., 132. 
10 Journ. Prakt. Chem. [2] xxx., 37. 
