SECONDARY STANDARDS. 
939 
(56), (27), (28), (29), (30) 
0*4s 
= 
0*4 
+ 0*00013 
72 
0*2s 
= 
0*2 
+ 0*00018 
73 
(32), (33), (73) 
0*lw 
= 
0*1 
+ 0*00032 
74 
0*ls 
= 
0*1 
-0*00038 
75 
(45), (73), (75) 
0*3s 
= 
0*3 
+ 0*00037 
76 
(74), (75), (35), (36) 
0*05s 
= 
0*05 
-0*00008 
77 
(77), (37), (38) 
0*025iS 
= 
0*025 
-0*00007 
78 
(39), (75), (40), (41) 
0*02s 
= 
0*02 
-0*00066 
79 
0*045 
= 
0*04 
+ 0*00015 
80 
(79), (43), (44) 
0*0l5 
= 
0*01 
+ 0*00012 
81 
(45), (79), (81) 
0*035 
= 
0*03 
+ 0*00000 
82 
(81), (46), (47), (48) 
0*0045 
= 
0*004 
-0*00019 
83 
0*0025 
= 
0*002 + 0*00018 
84 
(84), (49), (50) 
0*0015 
= 
0*001+0*00012 
85 
0*001« 
= 
0*001 + 0*00009 
86 
(51), (84), (85), (86) 
0*0035 
= 
0*003 + 0*00036 
(52), (83), (85), (86) 
0*005s 
= 
0*005 
-0*00076 
By a mean of 12 comparisons 20^= 10 a-{- 10m — 0'00386 gr.= 20 ounces— 0’00286 gr. 
By a mean of 12 comparisons 305=205+ lOm+0‘00361 gr.= 30 ounces+0‘00133 gr. 
Let W denote a commercial lb. of the same density as the lost standard troy 
pound. In air for which log A=7‘07832— 10, the lb. Pd appears to be equal to 
W+0'00169gr. Let (1000), [1000] denote two brass weights of nearly 1000 grains 
each ; (2000), (4000) two brass weights of nearly 2000 and 4000 grains each respect- 
ively. Then. 
No. of Comp. 
12 
12 
10 
4 
gr- 
(4000)-f(2000) + i{(1000) + [1000]} = Pd -0*00582 
(4000) =(2000) + (1000)+ [1000] -0*00550 
(2000) =(1000)+ [1000] +0*00154 
(1000) =[1000] +0*01360 
Hence gr. 
[1000] = 999*99296 
(1000) = 1000*00656 
(2000) = 2000*00105 
(4000) = 3999*99506 
The bronze weight (200) =199‘9971 grains (in air). 
By a mean of 28 comparisons, 405= sum of secondary standard lbs. Nos. 9 and 11 
+ (4000) + (1000) + (200) — 0‘0171 grain = 40 ounces— 0'0298 grain. 
By a mean of 40 comparisons, 505= sum of secondary standard lbs. Nos. 9, 11, 12 
+ (2000) + (1000)+0'0073 grain=50 ounces+0'0054 grain. 
By a mean of 60 comparisons, 1005= sum of secondary standard lbs. Nos. 9, 11, 
12, 13, 14, 16 + (4000) + (2000)+0‘0701 grain=100 ounces+0’0193 grain. 
By a mean of 68 comparisons, 2005= sum of secondary standard lbs. Nos. 9, 11, 
12, 13, 14, 16, 17«, 17^, 29, 30, 19, 21, 28 + (4000) + (1000)+0-023 grain = 200 ounces 
— 0'022 grain. 
By a mean of 26 comparisons, 3005= 2005+ 1005+ 0‘0304 gr.=300 oz.+0‘027 gf. 
By a mean of 20 comparisons, 4005= 3005+1005— 0*046 gr.=400 oz. +0*000 gr. 
By a mean of 20 comparisons, 5005=3005+2005-0*059 gr. = 500 oz. — 0*054 gr. 
The troy ounce weights marked 5 are deposited in the Exchequer. 
6 G 
MDCCCLVI. 
