uh; 2845: 1] 
Which differs from Mr. Woulfe’s refult by 8,5 ounces in 
excefs, which difference may be owing to his’ having ufed an 
oil of vitriol weaker than I fuppofed, and confequently contain- 
ing lefs ftandard, and to his ufing a common falt not perfectly 
pure, but containing marine Epfom, whereas my calculation 
‘is grounded on the fuppofition of its being perfe@ly pure. 
And laftly, he takes no notice of any fra@tion of a pound lefs 
than an ounce; and when all the calculations here employed ‘are 
confidered the difference of 8-in jo8 oz. will appear inconfi- 
derable. fore . 
prs. 
Further, fince 100 parts pure mineral alkali take up 143 
of the vitriolic ftandard, 51940 fhould take up - 74274 
And deduéting this from 81682 in the retort, we find 
an excefs of - - - - - 7408 
In effect, though Mr. Woulfe fays nothing of the 
ftate of the refiduum, yet Mr. Baumé, who ufes 
the fame proportion of ingredients, obferves there 
is always an excefs of vitriolic acid left in the 
retort. 
I now proceed to examine the quantity of marine acid 
produced: Since 11566 grs. of the alkaline folution 
contained (as already faid) 1680. of mere alkali, 
12,5 oz. (=5408,75 grs.) contained - > 704535 
This 
