296 plint's natueal history. [Book XXXV. 



pearance, and turns black on the application of nut-galls ; for 

 which reason it is known by the name of " paraphoron."^^ 



Liquid alumen is naturally astringent, indurative, and cor- 

 rosive : used in combination with honey, it heals ulcerations of 

 the mouth, pimples, and pruriginous eruptions. The remedy, 

 when thus used, is employed in the bath, the proportions 

 being two parts of honey to one of alumen. It has the effect, 

 also, of checking and dispersing perspiration, and of neu- 

 tralizing oftensive odours of the arm-pits. It is taken too, in 

 the form of pills, for affections of the spleen, and for the pur- 

 pose of carrying off blood by the urine : incorporated with nitre 

 and melanthium,^" it is curative of itch-scab. 



There is one kind of solid alumen, known to the Greeks as 

 " schiston,"-^ which splits into filaments of a whitish colour; 

 for which reason some have preferred giving it the name of 

 *' trichitis."^^ It is produced from the mineral ore known to 

 us as " chalcitis,"^^ from which copper is also produced, it 

 being a sort of exudation from that mineral, coagulated into 

 the form of scum. This kind of alumen is less desiccative 

 than the others, and is not so useful as a check upon bad 

 humours of the body. Used, however, either in the form of a 

 liniment or of an injection, it is highly beneficial to the ears ; 

 as also for ulcerations of the mouth, and for tooth-ache, if 

 retained with the saliva in the mouth. It is employed also 

 as a serviceable ingredient in compositions for the eyes, and 

 for the generative organs in either sex. The mode of pre- 

 paring it is to roast it in crucibles, until it has quite lost its 

 liquid form. 



There is another variety of alumen also, of a less active na- 

 ture, and known as " strongyle ;"^^ which is again subdivided 

 into two kinds ; the fungous, which easily dissolves in any 

 liquid, and is looked upon as altogether worthless ; and the 

 porous, which is full of small holes like a sponge, and in 

 pieces of a globular form, more nearly approaching white 

 alumen in appearance. It has a certain degree, too, of unc- 

 tuousness, is free from grit, friable, and not apt to blacken the 



19 " Adulterated." 20 See B. xx. c. 71. 



■■'I " Split" alum. Probably iron alum, the French ahem de plume ; of a 

 flaky, silky appearance. 23 <« Hairy alum." 



2-^ See B. xxxiv. cc. 2, 29. 

 ^* So called, according to Dioscorides, from the "round" form of the pieces. 



