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acid loft 24 grains of its weight, which efcaped in an aerial form. 
This air-was hepatic. 
Avnotuer ounce diffolved in boiling water left an infoluble 
refidue, which being heated in a crucible to rednefs weighed 165 
grains ; this refidue effervefced with acids, and feemed for the moft 
part calcareous. 
Tue folution by the teft of the nitrous folution of filver evidently 
contained fulphur, and the Pruffian alkali gave manifeft figns of 
iron. 
Tuts folution precipitated 25 grains of earth of allum, and 
therefore contained 16,6 grains of mere alkali. During the pre- 
cipitation of the earth of allum much hepatic air was emitted, 
and the earth was fullied by the fulphur, though only a few 
grains of this can be prefumed to be mixed with it. 
To find the quantity of fulphur in this kelp I diffolved two 
ounces of it in pure water, and faturated the folution with ma- 
rine acid ; the liquor became turbid, and partly by filtration and 
part by fpontaneous depofition, (for fome of the fulphur paffed 
through the filter) I obtained 8 grains of fulphur, which gives 
4 grains for each ounce, befides what exhaled in hepatic air. 
In order to eftimate the quantity of fulphur which a given 
quantity of mineral alkali is capable of containing, I diffolved 
4oo grains of cryftallized mineral alkali-in fix times its weight of 
water, (this quantity of the cryftals contained 80 grains of mere 
alkali) and to this I added 80 grains of fulphur, and boiled them 
for 
