- 504 LEGUMINOSZ. 
occasionally associated with tinea, which appears on its mar- 
gin, or separately on other parts of the body. 
“The remedy that I have found to be most certainly and 
rapidly effective is the solution in common vinegar or lemon- 
juice of Goa Powder. This rarely fails to effect complete removal 
of the disease after two or three applications repeated daily. 
“The mode of application is to dissolve a few grains of the 
powder in common vinegar or lemon-juice to about the consis- 
tence of cream, and then paint the solution over the eruption 
and for a little distance beyond its margin on to the sound 
skin. It causes no pain at first, but in the course of a few 
hours there is a sensation of a dull heavy nature, as though the 
skin had been bruised, the eruption becoming white, whilst 
the surrounding skin is stained of a dark colour. The sense of 
uneasiness, however, soon passes away, and the integument 
resumes its natural characters ; all traces of the disease disap- 
pear at the same time. Should any vestige of the eruption 
remain, or any indications of its return appear, a fresh appli- 
cation should be made. Ina few days the dark discoloration 
of the skin begins to fade, gradually merging’ into the normal 
tint. At the same time a change takes place in the eruption, _ 
which gradually regains the naturalcolour of the skin ; and by. 
the time that the discoloration caused by the powder fia dis- 
appeared, that of the eruption has also passed away, and the 
patient is well. Of course, it cannot be expected that these 
favourable results will always follow immediately. In chronic 
cases there is more obstinacy, and several repetitions of the 
application may be needed ; but in recent examples the result 
will be generally favourable, 
Chemical composition.— = Eis bia i is present i in Goa pow- 
- der to the extent of about 70 per cent., and when pure is @ 
pale-yellow powder, consisting of small wart-like crystals made 
up of leaflets and acquiring on exposure a darker tint. By — 
: repeated crystallization from glacial acetic acid it is obtained — 
pure in Herharteh of ae Ele et are fusible ae “e 
