39 



Cascarillill, Bitter ingi-edient of the bark of Croton 

 Eleuteria and Croton Sloani. Precipitate the aqueous extract 

 with acetate of lead, remove the lead from the filtered liquid by 

 means of sulphuret of hydrogen, evaporate, digest with animal 

 charcoal and concenti-ate until a pellicle forms on the surface, 

 wash the subsiding mass with alcohol and recrystallise in boiling 

 alcohol. — White, fine needles and tabular crystals, neutral, bitter, 

 fusible, non-nitrogenised, not volatile, very slowly soluble in 

 water, more readily in alcohol and ether, with purple-red colour 

 in concentrated sulphiiric acid. 



Castill, Bitter substance of the seeds of Vitex Agnus castus 

 (to be looked for in the luimerous other species of the genus). 

 Separates in crystals from the alcoholic tincture, dissolves little in 

 water; sohible in alcohol and ether, pi-ecipitable by alkalies. 



Castor Oil. Obtained by pressing the seeds of Ricinus com- 

 munis. Almost coloiirless, with a slight green-yellow tinge, of 

 thick fluidity, of indiS'erent smell and mild afterwards a little acrid 

 taste, has a density of 0'960, does not congeal at - 15°, but yields in 

 the cold a little graniilar matter; dissolves in any quantity of 

 absolute alcohol and ether, thickens at the air and becomes dry at 

 last; begins to boil at 26.5°, yielding various products. It 

 consists in the main of the glycerid of the ricinoleic acid. As 

 regards the solid fat there are different opinions; Bonis asserts 

 that it is the glycerid of a peculiar acid called by him Isocetic 

 acid, on account of its having the same composition as the cetic 

 acid of spermaceti. 



Catecliiii or Catecliuic Acid = C12 Hß O5 + 2 HO. In the 



Catechu — the aqueous extract of the wood of Acacia Catechu, of 

 the nuts of Areca Catechu, and of the leaves of Nauclea Gambir; 

 also in the kino — the hardened juice of the stem of Pterocarpus 

 Marsupium. To prepare it, exhaust finely pulverised catechu with 

 cold water first and boil it afterwards with eight times its quantity 

 of water in a tubvilated retort, while adding subacetate of lead, 

 until the solution is of a wine-yellow colour; filter the boiling 

 liquid and allow to cool under exclusion of the air. The white 

 granular mass which will have formed after 24 hours has to 

 be washed with cold water until every trace of lead is removed ; it 

 is then pressed and dried in the vacuum. — A white, granular sub- 

 stance, consisting of fine needles, and after trituration representing 

 a white loose powder, but of a partly yellow-brown colour when 

 the air in drying was not completely excluded ; without smell and 

 of a sweetish taste; dissolves in 16,000 parts of cold and in four 

 parts boiling water, readily in alcohol, in 120 parts cold and in 

 seven parts boiling ether; all these solutions have an acid reaction. 

 It imparts a dark-green colour to salts of oxyd of iron, yet pro- 



