454 M. Keller on Scammony. 



time, it solidifies to a white crystalline mass, which is bitartrate 

 of potash, without any admixtme of saccharate of potash. 



In a paper by Keller* on the constitution of scammony, which 

 he had already recognized as a glucoside, this chemist obtained 

 the following resv;lts, which are partially corrective of those he 

 had formerly obtained. 



A solution of purified scammony is digested for some days 

 with sulphuric acid, or saturated with hydrochloric acid. On 

 mixing this solution with water, fatty crystalline lamina? sepa- 

 rate, and the solution, on continued standing, deposits well- 

 formed crystals. On being purified and fused, they present the 

 appearance of a radiating mass. This substance is insoluble in 

 water, but dissolves in alcohol, and is neutral to test-paper. It 

 fuses at 37° to 38° C. It gave, on analysis, numbers which 

 correspond to the formula C^^ H^^ 0*. 



This neutral body is decomposed by treatment with alcoholic 

 potash. On the addition of sulphuric acid to the potash solu- 

 tion, a substance separates in white flakes, which melt under 

 water to oily drops, and solidify to a radiant crystalline mass. 

 Its fusing-point is 60^ to 61° C.; it is soluble in alcohol, with 

 an acid reaction. Its formula, deduced from that of its silver 

 salt, is C30 H28 0«. 



The other product of the action of alcoholic potash is a neu- 

 tral body which appears to be an alcohol. It is a fatty substance, 

 fusing at 40°, and has the composition C^^ H^^ 0^. 



The above neutral substance hence appears to be a compound 

 ether, and its formula would be C^^ H^^ 0^, according to which 

 its decomposition by potash is thus expressed : — 



C56 HS6 QS ^ C30 IpS 0^ + C26 H^S 02. 



Neutral body. New acid. New alcohol. 

 The acid and the alcohol are also obtained by directly treating 

 the resin with potash. 



When the sulphuric acid solution is agitated with ether, a 

 wine-yellow etherial solution is formed, which, on evaporation, 

 leaves a body presenting the reactions of an aldehyde, apparently 

 valerianic aldehyde. It is not improbable that formic acid or its 

 aldehyde is present. Besides the aldehyde, a substance is pre- 

 sent in the etherial solution which has many of the reactions of 

 a sugar. Its nature has not been satisfactorily determined. 



Keller also found that when an alcoholic solution of scammony 

 is mixed with ammonia and saturated with sulphurous acid, a 

 compound crystallizing in laminae is obtained, which appears to 

 be a combination of an aldehyde with bisulphite of ammonia. 



* Liebig's Annalen, Februai-y 1859. 



