172 



THE ATOMIC WEIGHTS. 



•0053 



This series of data is regarded by the editors as preliminary, and not 

 entitled to much consideration. The second series, which foUoAvs, was 

 the final one ; both represent vacuum standards : 



BBr.,. Ag. Ratio. 



4.467835 S-771268 77-415 



8.42315 1 10.880648 77.414 



I. 6551 II 2,137593 77-429 



S.032352 10.374201 77-426 



4.092743 5-285949 77-427 



2.389993 3.086842 77-425 



7.721944 9.974054 77-420 



Mean, 77.422, =h .0018 

 First series, 77.449, d= -0053 



General mean, 77.425, ± .0017 



Ramsay and Aston,* in their paper upon the atomic wei<j;ht of boron, 

 suggest that Abrahall's bromide may have contained hydrobromic acid, 

 Avhich would fully account for the low result obtained. They them- 

 selves adopt two distinct methods, the first one being the time-honored 

 determination of water in crystallized borax. The latter was prepared 

 from pure boric acid and pure sodium hydroxide. Results as follows, 

 reduced to a vacuum : 



Mean, 47. 1677, dm .00S6. 

 This we may combine with the previous determinations, thus : 



Rerzelius with Laurent 47-13, ± .0130 



Hoskyns-Abrahall 47.2866, =h .0171 



Ramsay and Aston 47. 1677, ± .0086 



General mean 47.1756,^.0066 



* Journ. Chem. Soc, 63. 211. 1893. 



