448 PHILOSOVHICAL TRANSACTIONS, [aNNO 1704. 



nitric acid required g4 grs. ; and 3dly. That 100 grs. of muriatic acid required 56 

 grs. for saturation. Which experiment ascertained the dormant affinity of this 

 earth to those acids. 



I also ascertained in the same way, 1st, That 100 grs, of sulphuric acid re- 

 quired 130 grs. of barytes. 2dly. That 100 grs, of nitric acid required 120 grs. 

 and Sdly. That the same quantity of muriatic acid required 96 for saturation ; 

 which gave the dormant affinity between the barytes and those acids. 



From these experiments I drew the following conclusions. 1st, That accord- 

 ing to experiment 1, the substance contained no saline parts, 2dly. That accord- 

 ing to experiment 2, it contained fixed air. Sdly. That according to experiment 

 3, it contained an earth somewhat similar to barytes. 4thly. That according to 

 experiment 4, it discovers no crystallizing water. 5thly. That according to 

 experiment 5, the substance contained no cobalt. (5thly, That according to ex- 

 periment 6, the substance contained no copper. 7thly. That according to ex- 

 periment 8, it contained a little iron. 8thly. That according to experiment Q, 

 the substance contained calcareous earth. Qthly. That according to experiment 

 10, the substance contained no argillaceous nor magnesian earth. lOthly. That 

 according to the last experiment, the base of this substance is distinct from the 

 barytes. 



To ascertain the quantity or proportion of component parts of this substance, 

 Exper. 1, One hundred grs. were dissolved in acid, and yielded 30 grs. of 

 fixed air. 



Exper. 1. The solution was diluted, and mixed with oxalic acid, by means of 

 which J- gr. of calcareous earth was separated (in the state of oxalate of lime), 



Exper. 3. The remaining solution was decomposed, and yielded 68 grs. of 

 pure earth. 



According to these experiments, 100 grs. of the analyzed substance contains 

 30 grs. of fixed air, 1 of calcareous, and 68 grs. of another earth, which may 

 be called Strontion earth ; and the remaining weight may be accounted for, from 

 the substance which gives it the colour, and which I suggest, from comparative 

 experiments, to be phosphate of iron and manganese ; the proportion of which 

 I could not accurately ascertain, on account of the smallness of the specimen 

 which I possessed, and which I employed for analysis ; but which I shall endea- 

 vour to ascertain by future experiments on a larger scale. 



In order to compare the nature of the substance with which it was accompanied 

 to the before-mentioned substance, I made the following experiments. This 

 substance was crystalized in six-sided prisms with pyramids, colourless, semi- 

 transparent, rather opaque towards the basis, and less hard than the other sub- 

 stance ; a certain quantity of it I reduced to fine powder, and submitted it to 



