64 THE ATOMIC WEIGHTS. 



STRONTIUM. 



The ratios which fix the atomic weight of strontium re- 

 semble in general terms those relating to barium, only they 

 are fewer in number and represent a comparatively small 

 amount of work. The early experiments of Stromeyer,* 

 who measured the volume of CO2 evolved from a known 

 Aveight of strontium carbonate, are hardly available for the 

 present discussion. So also we may exclude the determina- 

 tion by Salvetat,t who neglected to publish sufficient details. 



Taking the ratio between strontium chloride and silver 

 first in order, we have series of figures b}^ Pelouze and by 

 Dumas. Pelouze^ employed the volumetric method already 

 described under barium, and in two experiments obtained 

 the subjoined results. In another column I append the 

 ratio between SrCl, and 100 parts of silver: 



1.480 grm. SiClj = 2.014 grin. Ag. 73-486 



2.2IO " 3.008 " 73-471 



Mean, 73.4781, d: .0050 



Dumas,|| by the same general method, made sets of ex- 

 periments with three samples of chloride which had pre- 

 viously been fused in a current of dry hydrochloric acid. 

 His results, expressed in the usual way, are as follows : 



Series A. 



3.137 gmi. .S1CI2 =^ 4.280 grm. Ag. Ratio, 73.2944 



1.982 " 2.705 " 73-2717 



3.041 " 4.142 " 73-4186 



3-099 " 4-219 " 73-4534 



Mean, 73-3595- ± -0303 



* Schweigg. Journ., 19,228. 1816. 



f Compt. Rend., 17, 318. 1843. 



X Compt. Rend., 29, 1047. 1845. 



II Ann. Chim. Phys., (3,) 55, 29. 1859. Ann. Chem. Pharm., 113. 34. 



