130 APPENDIX 
found to be Pararabin. The gum contained 16-6 per cent. water, 
and yielded 5°83 per cent. ash, 
aiden draws attention to the fact that Pararabin is the 
chief constituent of the vegetable jellies known as Agar-agar, a 
Ceylon moss, both of which are used by the natives of India as an 
article of diet like Stereulia gum, and are supposed to be very 
strengthening. 
sample of gum said to be from Cochlospermum gossypium was 
found by him to be similar to that of Sterculia, but as it had pieces 
of lace bark attached to it, it was probably Sterculia gum, 
LINEAL. 
Linamarin. 
A, Jorissen and B. Hairs (Acad, roy. de Belgique (3) 21 (1891), 
529) have isolated a glucoside, linamarin, from the germs of Linum 
usitatissimum. The germs, coarsely powdered, were treated repeated- 
ly with boiling 94 per cent. alcohol, the latter recovered and the 
residue taken up with warm water. The resin and fat are 
separated, and the aqueous solution treated with a slight excess of 
lead acetate, After filtration and precipitating the lead with H?8 the 
liquid is evaporated to a syrupy consistency, This residue is extract- 
ed with boiling alcohol, the solvent recovered for the greatest part, and 
the remaining liquid mixed with ten times its volume of ether under 
constant agitation. The residue remaining on distilling off the ether 
istaken up with water and this solution concentrated. Standing over 
sulphuric acid for some time, the concentrated solution is converted 
into a crystalline mass of linamarin. For purification it is again 
treated with ether and alechol as above. Lastly, the principle is 
dissolved in two parts of warm absolute alcohol, and the solution 
cooled under agitation. The germs yield about 1°5 per cent. of 
the glucoside, which forms colourless needles possessing a refreshing 
but very bitter taste, is soluble in water and alcohol, but almost in- 
solubleinether, Concentrated sulphuric acid does not colour it ; dilute 
mineral acids decompose the glucoside into hydrocyanic acid, a fer- 
mentable sugar reducing Fehling’s test, and a volatile paras 
possessing some characters of ketones, and giving with iodine an 
potassium hydrate the iodoform reaction. Boilin g barium a. 
liberates ammonia. Linamarin contains C 47:88 per -cent., H 6°68 
per cent., N 5°55 per Soh y 39: ‘89 per cent. (Am, Journ, Pharm,, 
Dec, 1891 a 
