lo ESSAYS AND 0^>SERV'TIONS 



fand, are, ir is true, the conOitnent parts 

 of it \n all marles *; but the Ufferent 

 proportions, in which thefe are 'riixe.l with 

 the foluble part, are ahnoft infinite. 



E X P E R. V. 



Th e refidue of a drachm of clay-marie^ 

 ■which was eafily diftufible in water, 

 weighed 40 grains, and confifted ot e^ 

 qual proportions o£ clay and fine fand. 



EX PER. vr. 



A drachm of another clay-marle con-, 

 tained fifteen grains of unfoluble matter, 

 which was altogether clay. 



EXPER. 



* h muft be obfervei, that the refiJue of all or rood 

 rnaries contains, befides clay and fand, a confiderable 

 number ot flat ihining particles. Thefe particles are 

 uni'>lub!e in acids, as is evident from their remaining 

 in the refidue. ^'ew of tht-m fuflerany diminution of lu« 

 ftre in r')e fire. Whence they appear to be flakes of fo- 

 liaceous talc. 



