COMPARISONS OF THE AUXILIARY WEIGHTS IN 1844. 
807 
adjusted that no sensible difference could be detected between them, a weight V 
of 6-451 grains, and a weight W of 12-901 grains, all of platinum, were obtained 
from Mr. Barrow. Then, Y and Z being platinum weights of 20 grains each belonging 
to the two Robinson’s balances, the following comparisons became possible: — each of 
the weights R and S with Y+Z; each of the weights Y and Z with W4-V+ each 
of the weights Q; W with V+ sum of ten weights Q; V with the sum of the ten 
weights Q. In comparing PS with each of the weights T+A+Q, T+B+Q, T+C+Q, 
T+D + Q, the weight Q was changed at the end of every four comparisons, and thus 
each of the ten weights Q used in turn in a series of forty comparisons. 
The following comparisons of the auxiliary weights with Sp and RS, and with each 
other, were made for the purpose of finding their errors preparatory to a more accu- 
rate adjustment, and in order to obtain a series of weights to be used in finding the 
densities of T and of the five platinum lbs. of 7000 grains each, from June 4, 1844, to 
the end of the year. In the comparisons of A-J-B+C-f D+F with Sp and RS, X and Y 
denote the weights of the two detached pans. The counterpoise is placed in the 
left-hand pan. The numbers in each column are the readings of the scale in the 
position of equilibrium of the balance, when the weight at the head of the column is 
in the right-hand pan. In these, and all the other comparisons of weights in air, the 
results of the alternate weighings are arranged in separate columns. 
June 18, 1844. 
100 parts = 
0*2208 grain. 
A+B+C+D+F+Y. 
Sp+X. 
Sp+Y. 
27*80 
25*30 
22*90 
22*50 
27*00 
26*10 
22*90 
21*90 
25*20 
24*05 
21*40 
22*05 
25*30 
24*60 
26*45 
26*50 
24*60 
24*40 
29*50 
27*15 
24*40 
23*50 
28*65 
28*50 
23*55 
22*75 
27*30 
28*50 
23*00 
23*00 
29-30 
28*90 
22*55 
22*20 
30*10 
29-65 
22*40 
21*90 
30*40 
29*75 
245*80 
237*80 
268*90 
265*40 
10(A + B + C + D + F + Y)iil0(Sp + X) + 8*0 parts. 10(A + B + C + D + F + X)£i:10(Sp + Y) + 
A-fB-f-C + D + Fil:Sp + 0*001 27 grain. 
June 12, 1844. 
100 parts = 
0*2293 grain. 
RS+X. 
a+b+c+d+f+x. 
RS+Y. 
21*20 
20*70 
18*60 
19-60 
19*00 
21*10 
18*10 
20*20 
19-30 
21*60 
18*70 
20*00 
19*50 
20*80 
18*50 
20*00 
19-40 
21*30 
19-10 
19-35 
18*70 
20*80 
18*00 
19-85 
117*10 
126*30 
111*00 
119-00 
6(A + B + C-|-D + F + Y)£:6(RS + X)-9-2 parts. 6(A + B + C + D-|-F + X)^6(RS + Y)-8-0 parts. 
A + B + C + D + F:2:RS— 0*00329 grain. 
