74 STUDIES ON APPLES. 
iment the time of boiling was seven hours, and the reaction product 
was examined as follows: It was filtered and the insoluble residue on 
the filter weighed. Sulphuric acid was removed from the filtrate with 
barium carbonate, and sugar and soluble solids were determined. 
They found 28.3 per cent of nonhydrolyzed material, 39.8 per cent of 
sugar (calculated as dextrose), and 46.36 per cent of gum; in all, 114.46 
per cent. 
Reichardt“ prepared from carrots pararabin, a body somewhat dif- 
ferent from Scheibler’s arabie acid, but readily converted into it, and 
showing a carbohydrate percentage composition of C,,H,,O,,. 
Barfoed’ studied changes of various arabic acids from soluble into 
insoluble form by standing in alcohol or on drying. 
Scheibler* found that beet marc, previously extracted with alcohol, 
yielded to water a body which could be obtained ash free, and which 
possessed a rotatory power of over +200°. 
Von Lippman“ described a body, y-galactan, of high rotatory power 
from the scums of sugar manufactured from unripe beets, possibly 
very similar to the metapectic acid obtained by Scheibler. 
Muntz* suggested that the galactose complexes so widely distributed 
in plants were probably the sources of the galactose radical in lactose 
in milk. 
Battut,’ Chevron,’ and Pellet” discussed the influence on the polari- 
zation of sugar of the dextrorotatory pectin dissolyed on boiling 
sugar-free beet mare with water. Basie lead acetate precipitates it 
completely, thus disposing of the question of its interference with 
polarimetric measurements. 
Weisberg ‘ confirms the view of Scheibler that gelatinous hot water 
extract from beet mare exhausted by alcohol was a pectin. On heat- 
ing with water the acidity of the solution gradually increased. By 
sulphuric acid hydrolysis of the pectin, he also obtained a furfurol 
yielding sugar (arabinose). 
Wohl and Van Niessen“ discuss the work of Scheibler. Pectins of 
beet mare were considered to be insoluble in water, unless rendered 
soluble by hydrolysis, and to be slowly changed to soluble forms by 
hot water, and much more rapidly by acids and alkalis. For example, 
@ Ber. d. chem. Ges., 1875, 8: 807. 
bJ. prak. Chem., 1875, [2] 11: 186. 
¢ Neue Zts. f. Riibenz., 1879, 3: 341. 
d Ber. d. chem. Ges., 1887, 20: 1001. 
Ann. chim, phys., 1887 [6], 10: 566. 
J Suere indigéne, 1888, 32: 285, 311, 333, 357, 415, 456. 
9 Neue Ztg. f. Rubenz., 1588, 20: 169. Sucre belge, 1888, 13: through Chem. 
Ztg. R., 1888, 12: 82. 
/ Sucre indigéne, 1888, $2: 390. 
t Neue Zts. f. Riibenz., 1888, 21: 325. 
k Zts. Ver. d. Zucker-Ind., 1889, 39: 924. 
Pee Meo. 
