Anah)fis of the Air. 189 



proportion of calx, that the worthy Dr. Slave 

 found remaining, after the diftilling and 

 calcining two ounces of calculus, "one ounce* 

 <e and three drams of which (he fays) eva- 

 €C porated in the open fire ( a material cir- 

 " cumftance, which the Chymifts rarely en- 

 " quire after) of which we have no ac- 

 " count/' Thilof. TranfaSi. Lowthorp's A- 

 hridgment. Vol. III. />. 179- The greateft 

 part of which was, we fee by the prefent 

 Experiment, raifed into permanently elaf- 

 tick Air. 



By comparing this diftillation of the cal- 

 culus with that of Renijh Tartar in Expen 

 73. we fee that they both afford more Air 

 in diftillation, than any other fubftances : 

 And it is remarkable, that a greater propor- 

 tion of this new raifed Air from thefe two 

 fubftances, is reforbed and iofes its elafti- 

 city, in ftanding a few days, than that of any 

 other bodies, which are ftrong fymptoms 

 that the calculus is a true animal Tartar. 

 And as there was very confiderably lefs oil* 

 in the diftillation of Remfl) Tartarean there 

 was in the diftillation of the Seeds and folid 

 parts of vegetables 5 fo I found that this 

 calculus contained much lefs oil than the 

 blood or folid parts of animals, I 



