ART. IV. 2. 8. i. SORBENTIA. 55 



drachms of mercury, they are faid to unite with much lefs la- 

 bour of trituration, than the hog's fat and mercury alone. 



VIII. i. Abforptions in general are increafed by inanition ; 

 hence the ufe of evacuations in the cure of ulcers. Dr. Jurin 

 abforbed in one night, after a day's abftinence and exercife, 

 eighteen ounces from the atmofphere in his chamber ; and eve- 

 ry one muft have obferved, how foon his fheets became dry, 

 after having been moiftened by fweat, if he throws off part of 

 the bed- clothes to cool himfelf ; which is owing to the increafed 

 cutaneous .abforption after the evacuation by previous fweat. 



2. Now as opium is an univerfal ftimulus, as explained in 

 the article of Incitantia, it muft ftimulate into increafed action 

 both the fecretory fyftem, and the abforbent one ; but after re- 

 peated evacuation by venefe&ion, and cathartics, the abforbent 

 fyftem is already inclined to aft more powerfully ; as the blood- 

 veflels being lefs diftended, there is lefs refiftance to the progrefs 

 of the abforbed fluids into them. Hence after evacuations opi- 

 um promotes abforption, if given in fmall dofes, much more 

 than it promotes fecretion 5 and is thus eminently of fervice at 

 the end of inflammations, as in pleurify, or peripnuemony, in 

 the dofe of four or five drops of the tincture, given before the 

 accefs of the evening paroxyfm ; which I have feen fucceed 

 even when the rifus fardonicus has exifted. Some convulfions 

 may originate in the want of the abforption of fome acrid fecre- 

 tion, which occafions pain ; hence thefe difeafes are fo much 

 more certainly relieved by opium after venefection or other 

 evacuations. 



IX. i. Abforption is increafed by the calces or folutions of 

 mercury, lead, zinc, copper, iron, externally applied ; and by 

 arfenic, and by fulphur, and by the application of bitter vegeta- 

 bles in fine powder. Thus an ointment confiding of mercury 

 and hog's fat rubbed on the (kin cures venereal ulcers ; and ma- 

 ny kinds of herpetic eruptions are removed by an ointment cori- 

 fifting of fixty grains of white precipitate of mercury and ah 

 ounce of hog's fat. 



2. The tumours about the necks of young people are often 

 produced by the abforption of a faline or acrid material, which 

 has been depofited from eruptions behind the ears, owing to de- 

 ficient abforption in the furface of the ulcer, but which on run- 

 ning down on the Ikin below becomes abforbed, and fwells the 

 lymphatic glands of the neck ; as the variolous matter, when 

 inferted into the arm, fwells the gland of the axilla. Some- 

 times the perfpirative matter produced behind the ears becomes 

 putrid from the want of daily warning them, and may alfo caufc 

 by its abforption the tumours of the lymphatics of the neck, 



In 



