316 



diffei'ent plants, the latter has been found as yet only in the order 

 of Compositse, at least to any considerable extent. 



Starch or inulin having been observed in the substance left after 

 filtering and washing, this substance is tied up in ga\ize and 

 kneaded. Collect the white powder deposited from the united 

 liquid on a filter, dry at 110°, and weigh it. The liquid is thrown 

 away, as the substance before kneaded had been exhausted already 

 by cold water. 



In order to find out the form and size of the starch or inulin 

 obtained, they have to be examined under a microscope magnifying 

 at least 400 diameters; after this, try their behaviour to warm 

 water in order to determine their solubility or the temperature 

 required for forming a paste. Any heterogeneous substance that 

 has been kneaded out together with starch or inulin will remain 

 on dissolving in water; as, for instance, oxalate of lime, which, on 

 burning, yields carbonate of lime, the weight of which gives the 

 weight of the oxalate of lime according to 625 (Ca O + CO2) 

 = 1025 (Ca O + C2 O3 + 2HO). The weight of the oxalate of 

 lime found in this way must be subtracted from that of the starch 

 or inulin. 



After the substance has been exhausted in the above manner by 

 cold and lukewarm water, and eventually by kneading, determine 

 its weight whilst still moist. Now take 5 grams of it, dry at 

 100°, weigh, calculate from it the weight of the whole residue, 

 conceived dry, and subtract the latter weight from that of the 

 substance, exhausted by ether and alcohol. The rest represents 

 the weight of the substances including eventually starch or inulin; 

 the weight of which, as found above, has to be subtracted from 

 the rest in order to give the weight of the matters soluble in water. 



Heat the aqueous solution, obtained clear by filtering and sub- 

 siding, in a porcelain dish to the boiling-point; boil for about a 

 quarter of an hour and allow to cool. Any turbidness or flocky 

 precipitate is produced by albumin. Let subside, collect on a 

 weighed filter, dry at 110°, and weigh. The albumin obtained 

 is mostly of a dark colour, and, consequently, impure; but the 

 colouring matter is hardly removable and is of too little amount 

 to impair the numerical result. 



Concentrate the filtered liquid to about 100 grams at a tem- 

 perature not exceeding 70° to 80° (if, as usually, a little albumin 

 should separate again, it must be collected and added to that 

 obtained before) ; evaporate a small sample of it on a watch-glass 

 to a thicker consistence, and allow both portions to stand cold. 

 In case of crystals having formed in either of these liquids — a 

 rare occurrence — evaporate the whole liquid to a small bulk, and 

 keep in the cold. Collect what will have crystallised on a filter, 

 wash with a little cold water, purify by recrystallising in hot 

 water, and examine according to IL, B, a or h or c. 



