312 



a gi'anular or of a crystalline form, is collected in a funnel, the 

 neck of which is loosely covered by a glass stopper. Wash the 

 sediment, after the liquid has run off, with a little cold water, and 

 submit it to a series of experiments comprising its basic as well as 

 its acid constituents. It will prove most probably a salt, and 

 perhaps acetate of ammonia, the two constituents of which have 

 been supplied by the testing chemicals. 



C. — Examinati(y>i of the solid mass. 



It may contain wax, resin, fat, chloropliyll. After the water 

 has been removed by gently heating for some time, determine its 

 weight and note down its external characters. Next let three 

 times its weight alcohol of 70 °/q act on it warm for half an hour, 

 keep cold for one day, filter and wash the remaining part with a 

 little alcohol of the same strength as before. 



(a) Shake a sample of the filtrate, which may be possibly 

 coloured by chlorophyll, with animal charcoal for some time and 

 treat, if the coloiir has become lighter, the whole filtrate in the 

 same way, filter and evaporate. The remnant is a resin, and has 

 to be tested as indicated on page 296. 



(6) Free the undissolved portion of C from alcohol at a gentle 

 heat, weigh again (to ascertain the weight of the dissolved resin), 

 and treat with ten times its weight alcohol of 90 °l^ hot. Usually 

 a complete solution will be effected ; any remaining body is fat — 

 ya^o?!^— -which is rinsed repeatedly with small quantities of warm 

 alcohol of 90 7^. 



a. The undissolved fat-oil is generally of little amount, and 

 allows only a few experiments concerning its taste and smell, its 

 capability of drying when exposed in thin layers to the air, and 

 its solubility in different solvents. If an oil has been obtained 

 already under Ä, the oil of C is always identical with it and 

 needs no further examination. 



ß. The hot filtered alcoholic solution of the substance C 

 deposits most of the wax on cooling. Let the whole stand in the 

 cold for one day, collect the deposit on a weighed filter, wash 

 with cold alcohol of 907o? tlry at a mean temperature, weigh and 

 determine, as far as possible, its physical properties including 

 fusing-point. Generally, the quantity obtained is insufiicient for a 

 thorough investigation, but if there be a sufiiciency of the wax, 

 the latter is purified by repeatedly dissolving in hot alcohol; 

 afterwards its constitution is determined by treating with potash- 

 ley, or if necessary, by fusing it with caustic potash, and by 

 examining the products obtained. 



7. The alcoholic liquid, left after the separation of the wax, 

 may retain only tii\ces of fat and wax, and deserves no further 

 consideration. 



