NITROGEN. 43 



In the later series there are but two experiments, as fol- 

 lows : 



Unfiised. Fused. 



157.4964 157-488 



157.4940 157-480 



Mean, 157.4952 Mean, 157. 4S4 



General mean, 157.486, i .0003 



Now, to combine all four sets of results : 



Penny 157.4417, ± .0033 



Marignac 157.4236, ± .0061 



Stas, 1st series 157.4740, dz .0014 



Stas, 2d series 157.4S60, i .0003 



General mean 157.479, ±.0003 



For the direct ratio between silver nitrate and silver chlo- 

 ride there are tw^o series of estimations. A weighed quan- 

 tity of nitrate is easily converted into chloride, and the 

 weight of the latter ascertained. In two experiments Tur- 

 ner* found of chloride from 100 parts of nitrate : 



84-357 

 84-389 



Mean, 84.373, zb .011 



Penny,t in five determinations, found the following per- 

 centages : 



84-370 

 84.388 



84-377 

 84.367 

 84-370 



Mean, 84.3744, zb .0025 



The general mean from both series is 84.3743, =b .0025. 



The ratio directly connecting silver nitrate with ammo- 

 nium chloride has been determined only by Stas.:{: The 



*Phil. Trans., 1833,537. 



t Phil. Trans., 1839. 



\ Aronstcin's Translation, p. 309. 



