46 
:\IE. ^Y. DE LA EUE AXD M. H. MULLEE OX 
It will be observed from the preceding numbers, that the resin, which has the propeidy 
of agglutinating on being masticated, is richer in carhon than that first thro^wi down by 
water from their alcoholic solution. The peculiar characters of these substances did 
not, however, permit of any formulae being determined for them. 
Sycoretin is almost white ; it is very brittle. It melts in boiling water to a thick 
liquid, floating on the surface, and when powdered it becomes so electric that it flies out 
of the mortar. In water, dilute acids, alkaline solutions, or ammonia, it is insoluble ; but 
it is readily soluble in alcohol, ether, chloroform, oil of turpentine, &c. 
In order to ascertain whether sycoretin v/as allied to that class of bodies called gluco- 
sides (for example, jalap ine), the following experiments were made : — 
Action of Suljylmric Acid on Sycoretin. 
A portion of the sycoretin, prepared as stated above by fractional precipitation, was 
added to concentrated sulphuric acid; it was readily dissolved, formmg a fine deep 
red solution, wdiich gave off only a faint odour of sulphurous acid when kept for several 
days. By exposure to the air, or on addition of water, a brownish precipitate deposited, 
which differed from the original solution by its lesser solubility; the aqueous liquid con- 
tained a trace of a sulpho-copulate acid, but no saccharine substance could be discoA’ered. 
Treated with a concentrated solution of potash, analogous results were obtained. These 
experiments show that sycoretin cannot be classed with the glucosides; moreover, all 
attempts to place this substance in connexion with some of the classified organic com- 
pounds were unsuccessful, and we are therefore constrained to leave it for the present 
among the so-called resins, under which term are comprised all sorts of bodies, acid and 
neutral, which have nothing in common except some physical resemblance. 
Action of nitric Acid on Sycoretin. 
It appears that the only products of the action of concentrated nitric acid are a pecu- 
liar nitro-compound and a small quantity of oxalic acid, no picric acid being formed. 
On submitting sycoretin to the action of nitric acid, the powdered resin w^as introduced 
in small quantities into the acid at the ordinary temperature, and when the action had 
somewhat subsided, the acid was boiled for some time, when every particle of resin dis- 
appeared. The resulting yellow liquid was mixed with water, when a copious precipi- 
tate of a pale yellow colour was formed. The precipitate was filtered off, and washed 
with water. The filtrate, when freed from nitric acid by evaporation, gave an addi- 
tional precipitate of the nitro-compound on admixture ■with water. The nitro-compound 
has slightly acid properties, and is readily soluble in solutions of potash and ammonia. 
Carbonate of potash also dissolves it, but there is no evolution of carbonic acid, even 
when the solution is warmed. All the solutions in alkalies are dark yellowish brown, 
and leave on evaporation an amorphous residue. Lead and other metallic salts give 
coloured precipitates with its solution, but, as might be expected, no definite compounds 
