On the Animal Calculus, 193 
arid, fifteen Grains, did, when a cubic Inch of 
Sp. of Nitre was poured on ir, diffolve in 
two or. three Hours, with a large Froth, and 
generated forty eight cubic Inches of Air^ 
none of which loft its Elafticity, in Handing 
many Days. A like Quantity of Tartar, hav- 
ing Spirit of Nitre poured on ir, was at the 
fame time diflblved, but no elaftic Air was ge- 
nerated, notwithftanding Tartar abounds fo 
much with Air* 
Small Pieces of Tartar and Calculus were 
in twelve or fourteen Days diffolved in Oil of 
Vitriol ; the like Pieces of Tartar and Calculus 
were diffolved in a fevv Honrs by Oil of Vi- 
triol, into which there was gradually poured 
near an equal Quantity of Spirit of Harts-hom 
made with Lime, which Mixture made acorn 
^fiderablc Ebullition and Heat. 
6, Tho’ the remaining Calx of the DifHI- 
lation of Tartar, mns per and has 
therefore Sal Tartar in it ; and tho’ the Calx 
of diftilled Calculus^ does not run per de- 
liquium,, and has confeqncntly no Sal Tartar 
in it ; yet it cannot thence be inferred, that 
the Calculus is not a rartarine Subftance; be- 
caufe Sal Tartar it felf, when mixed with an 
animal Calx^ diftills all over, Co that the Calx 
O . will 
