46 J. F. Tennant— 0« Standard Weiglits. [No. 1, 



X =;i= O3 in ail- + hook &c. in water + 2'72 — ^ at 10'02 divisions. 



then, removing O3 froua water, carefully drying it, and phicing it in the 

 pan, I found after adding 180 minims of water 



10 



Hence the loss of weight apparently = O.3 + O.q^ + O.qoj + 0.qq_j + 



My approximate calculations gave me the sum of the above four 

 weights as 167'5l!00 grains, and the value of the rider is approximately -ji^th 

 of a grain, the difference from the true value being negligible. Hence the 

 loss of weight between air and water was 167'5528 grains, and, though I 

 did not observe the Barometer, it may be considered as 29"46, and the tem- 

 perature 87°-5; this gives A O3 = 8-5649. 



Again on July 7th, I found in the same way. 



(A) X + 5 =^ ^3 in water + hook &c. in water 



+ 167-54! grains + 3 ^ at 13 30 Div. 



R 



(B) X + 5 ~ water + hook &c, in water 



+ 167-51 grains + 6 ^ at4'72 Div. J 



and, after adding 169 minims of water. 



R P 



(C) X + 5 — ^ ^ O3 in air + hook &c. in water + 7 ^ at 14-80 Div, 



Bar. 29° -445. 



Temp, 

 water 84 25 F. 



R R 

 (D) X + 5 y-i =ii= O3 in air + hook &c. in water + 9 -j^ at 8-35 Div. 



Temp. 85°'7F. 



Hence by interpolating between (A) and (B) 



X + 5 ^ O3 in water + hook &c. in water 



4- 167-54 o-rs 4- 4-1 4, I Temperatures 

 + ib/04gis. +4 14— I WaterS4°-25F. 



and from (C) and (D) V Aii- 85-7 



R T? 

 X + 5-^ =^03 + hook &c. in water + 8-49 



10 10 J 



m. 



Bar. 29-445 



Thus the loss of weight was apparently 167-4965 grains, and A O3 = 8-5676. 

 Giving this last result triple weight, on account of better observing, we have 

 as a mean ; A O3 = 8-5669 : which may be considered the density' for all 

 the weights of this set ; and which will not be altered by the true values of 

 the weights used, being substituted for the approximate ones. 



