50 



J. F. Tennant — On Standard Weights. 



[No. 1, 



Abstract of Comparisons. 

 1879 May 24, 0^ = 479-997632 P S. grain. 

 „ 28, „ -997489 „ 



30, „ -996732 

 81, „ -997266 

 „ June 1, „ -996911 



Mean 0^ = 479 997206 ± 0001 15 P S. grains. 



I have received, from the Meteorological Reporter to the Government 

 of Bengal, the following mean data for Calcutta which I take as the defini- 

 tion of Standard Air 



in. 



Eeduced Barometer,... 29787 \ 



o f whence A Ag 



Temperature, 79'0 F. { = 7 06510. 



Humidity, 0-76 percent. / 



Hence I have weight of = 479 997206 grains of P S. 

 Deduct displaced Standard Air = — 0-065178 

 Add Standard Air for ^s^W = + 0-068571 



Oj = 480-000599 grains of English Com- 



mercial Pound. 



This value differs slightly from that sent me and which I have quoted 

 before. 



Sectiok VI. — On the determination of ilie errors of single loeiglits. 



In the interval hetweeu Oj and O^q there are, in all English bullion sets, 

 ■weights O5, O4, O3, and Og ; so between O^o and Ojoo come O30 OgQ O^^ 

 and O5Q, and so on. 



Between these weights we may make comparisons giving the following 

 equations : 



s O5 + O4 + Oi + ± e («) 



= 05 + O3 + O3 + ^'1 ± e (S) 



= O4 + O3 + Oo + Oi + x\ ± e {e) 

 O5 = O4 + + ±6 e being the p. e, of one com- 



05 = 03 + 03. + iTg + e [parison. 

 0^ = 03 + 01 + + e 



03 = 00 + 01 + a-j + e _ 



Hence we have Oo = 2 O^ + a:-^ — + Xc, ± & \/ 8 



03 = 3 Oj + A'5 + x^ — jfg + x„ ± e \/4 



04 = 4 Oi + a?5 + 2x^ — a?3 + 0-3 ± e <\/7 



05 = 5 Oj + Xr, + 2x^ — + 2.^2 ± e \/Io 



