Chemistry and Physics. 463 
gave a brilliant mirror. Saturated with hydrogen sulphide, it 
became a magma of crystals of methyl sulph-aldehyde. Estimated 
by its reducing power, however, the liquid a magi but a little 
more than ‘5 of one per cent. of aldehyde. The author subse- 
quently prepared methyl formate, by distilling methyl alcohol 
recently saturated with hydrochloric gas, from calcium formate, 
r 
ale ote: ‘carbonic ‘eee jarhauke acid, ‘and marsh gas, the two 
latter in small proportion. —Liebig’s Annalen, elxxvi, 128, Feb., 
1875. . Be 
4, Composition of oe mh Pte —Gmavp hasmadea minute 
oe of the chemical characters of gum cee e 
on the water bath for tw enty-four hours, with fifty times its sep 
water, much of it is transformed into a soluble e gum, which no 
ayia swells after drying; this new substance is pectin; (3) 
that under the action of water containing one per cent of acid, the 
production of pectin takes place in two or three hours. It be- 
comes entirely soluble, and abe pr dolrlitates pectin, not arabin, 
from the oa Alkalie s change it into Ash and meta- 
ectates. Hence gum tragacanth consists for the most part of a pec- 
tic principle tipi ble in water, apparently identical ‘with Fremy’s 
pectose, From it, by precipitating the pectin solution by barium 
emitinipiale ater’ Sotastatbiee te sat. April 875 
4 , 
has sought to throw some light upon it by carefully examining 
malted barley for both these Ayes ces. Five kilograms of 
d barley 
grams ninety-five per cent alcohol, ne e wid oth liquid mixed 
nana pe 
than one-fourth its weight of water. “The ower aqueous layer, 
treated with a little barium hydrate, was ened filtered, and 
polarized. It rotated to the right, but contained two sugars, one 
reducing the ~~ er test, the other not. Upon evaporation to 
? 
dryness and extraction with alcohol, the two sugars were sepa- 
rated by fra oak phonies: In this way 0°6 of one 
- of hphiveert ir wa ined from the ma 
