Specific Gravity of Vapours and Gases. 



No. 



II. 

 III. 

 IV. 



V. 



Weight of | Weight of „ .. , 

 vessel with vessel with ^ a P acit y ot 

 air, water, | ^ vessel, 



R. W. v ' 



grms. 

 55-8237 

 572438 

 56-1273 

 55-3758 

 51-5725 



grms. 

 234 053 

 235-807 

 233-255 

 232-000 

 231 020 



cub. cent. 

 178-2293 

 178-5632 

 176-82/7 

 176-6242 

 179 3475 



V-V,. 



cub. cent. 

 16051 

 1-9390 

 0-2035 

 0-0000 

 2-7233 



«(V-V 4 )*;V-s(V-V 4 ). 



grms 



4-0808 



4-9297 



05174 



0-0000 



6-9238 



cub. cent. 

 176-6242 

 176C242 

 176-6242 

 176 6242 

 176-6242 



The weight of the vessels with the solid glass threads is now 

 I. . . B 1 +s(V 1 -V 4 ) 3 

 II. . . Ra + s(V 4 -V 4 ), 

 III. . . R 3 + S (V 3 -V 4 ). 



Amongst these R 2 + s(V 2 — V 4 ) is found to be the greatest. 

 Hence the weights of the other glass vessels must be subtracted 

 from this in order to learn the weights of the glass which has 

 to be added to each vessel, so that they all may possess the 

 above weight. These weights are made out of glass rods whose 

 finely drawn-out ends are broken off, or added to by fusion in 

 the flame until they are sufficiently heavy ; they are then in- 

 scribed with the number of the vessel to which they belong. 

 The following Table contains the adjustment of the weights for 

 the foregoing vessels : — 



No. 



E. 



s(V-VJ. 



R-N(V-V 4 )=H. 



n 2 -n 



n+(rr,-n). 



I. 



II. 



III. 



IV. 



V. 



55-8237 

 57-2438 

 56-4273 

 55-3758 

 51-6725 



4-0808 

 4-9297 

 0-5174 

 0-0000 

 6-9238 



59-9045 

 621735 

 56-9447 

 55-3758 

 58-5963 



2-2690 

 00000 

 5-2288 

 6-7977 

 3-5772 



621735 

 62- 173.1 

 62 1735 

 62-1735 

 621735 



When any one of these adjusted vessels is mentioned, the 

 corresponding glass weights II 2 — II are always supposed to be 

 included. The numbers in the last vertical column do not re- 

 present the weights of the separate vessels with the greatest 

 degree of accuracy, as no allowance is made for variation during 

 the weighings in the amount of atmospheric moisture and den- 

 sity. For the purposes of the following investigation, it suffices 

 to determine with the utmost accuracy the differences of weight 

 which the separate vessels possess. This is accomplished as 

 follows : — Vessel I. is laid on the right-hand pan of the balance, 

 vessel V. on the left-hand pan, and the position of equilibrium 

 of the balance ascertained ; V. is then replaced by each of the 



* s=2-5424. 

 B2 



