SCAMMONY 477 



from dark grey to dark brown or nearly black, the surface being often 

 covered with a grey powder. It breaks very readily, and the freshly 

 exposed surface is glossy, resinous, often more or less porous, and 

 of a dark brown or nearly black colour. Thin fragments, however, 

 when viewed by transmitted light, are seen to be brown in colour 

 and translucent. It is very easily reduced to an ash-grey powder, 

 and readily yields a milky emulsion when rubbed with water. 

 Scammony has a characteristic cheesy odour and an acrid taste. 



Very fine qualities of the drug which, however, are scarce, differ in 

 being of a golden brown colour, almost transparent in thin fragments, 

 and less porous. 



The student should observe its brittle nature, translucent brown 

 colour in thin fragments, and characteristic odour ; it yields a milky 

 emulsion when rubbed with the wet finger, a character that 

 distinguishes it from scammony resin, which does not emulsify when 

 so treated. 



Constituents. Pure scammony contains about 88 or 90 per cent 

 of resin identical with that obtained from the root (see p. 351) and 

 entirely soluble in ether ; the residue consists principally of gum. 

 But scammony of such purity as this is seldom met with in commerce. 

 Good qualities yield from 70 to 80 per cent, of resin to ether, and are 

 known as ' virgin ' scammony. 



Uses. Scammony is used as a brisk cathartic and vermifuge, 

 especially for children. 



Adulteration. The high price of scammony and its plastic nature 

 before it is dried invite and facilitate adulteration. Starch, chalk, 

 and earthy matter are frequently used to increase its weight, and 

 occasionally other resins are fraudulently mixed with it. 



Adulteration with inorganic matter is readily detected by incin- 

 eration. Good scammony should not yield more than 3 per cent, 

 of ash. Starch is easily recognised by microscopical examination 

 or by the iodine test, but traces of the starch of scammony root are 

 often present in genuine scammony, and caution must be used in 

 concluding that the drug has been adulterated. Most foreign resins 

 may be detected by dissolving the drug in hot solution of potassium 

 hydroxide ; on the addition of an acid, scammony resin is not pre- 

 cipitated whereas most foreign resins are. 



Inferior scammony is usually tough and has a dull fracture, small 

 splinters being opaque instead of translucent. Factitious scammony 

 that was practically free from resin soluble in ether has even been 

 offered for sale as genuine scammony. 



