98 ABSOLUTE ATOMIC WEIGHT. 



Lars Svanberg made three excellent distillations with 

 lime according to the method of Erdmann and Marchand. 

 Hg : HgCh =r 200 : 271 ==0.73 Soi. Change 48 low. 



Svanberg's Distillations, 1848. 



No. Sublimate. Mercury. Analyt. Ratio. Excess. 



1 12.048 8.889 '73 7 2I l w> 



2 12.529 9.2456 794 7 low. 



3 12.6491 9.3363 Sio 9 high. 

 Grammes. Mean 0.73 795 6 low. 



We notice, the deviations are to both sides, very small, 

 except the first. If this first attempt were discarded, the final 

 excess would be i high only. 



Taking all determinations as of equal value, the mean 

 analytical excess is 6 low, which represents % of the change 

 due to o.i, or 0.012 on the atomic weight, in opposite direc- 

 tion, hence giving a positive departure. 



That is 35.512 or say 35.51. 



The real meaning is that 35.5 is the true atomic weight, 

 with a. possible deviation indicated of o.oi high, but not fixed, 

 as it is within the limit of precision. 



Millon, in 1846, had made four less accurate distillations, 

 obtaining a mean analytical ratio of 0.73 845 which is 44 



high- 

 Turner, in 1833, set free mercury by means of stannous 

 chloride, collecting and weighing the mercury thus set free. 

 His results are: 



Xo. Sublimate. Mercury. Analyt. Ratio. Excess. 



1 60.682 44.782 0.73 798 3 low. 



2 99.06 73-9 784 17 low. 

 Grains. Mean 0.73 791 10 low. 



The work of Svanberg in 1848, is considerably more 

 accurate than that of Turner in 1833, as is but natural, 

 especially as Svanberg had the benefit of the excellent work 

 of Erdmann and Marchand. 



If Svanberg's name were not already associated with iron, 

 it would belong here for chlorine. 



