RICHARDS. — RETENTION AND RELEASE OP GASES, 415 



The Effect of Tijie on the Composition of the Gas 



RETAINED BY CUPRIC OxiDE. 



First Series : Temperature, 500°. 



(Argentic Chloride easily melted; Plumbic Chloride scarcely melted.) 



(68) 0.29 c.c. gas from 1 gr. CuO heated 2 hours contained 25 per cent oxygen 



(69) 0.29 " " " " 23 



Average 24 per cent oxygen. 



(70) 0.38 c.c. gas from 1 gr. CuO heated 8 hours contained 15 per cent oxygen. 



(71) 0.42 " " " " 14 



Average 14.5 per cent oxygen. 



(72) 0.46 c.c. gas from 1 gr. CuO heated 16 hours contained 8 per cent oxygen. 



Second Series: Temperature, 520°. 



(Just below the melting point of Argentic Iodide, but distinctly above that 

 employed in the last series.) 



(73) 0.15 c.c. gas from 1 gr. CuO heated for 15min. contained 23 per cent oxygen. 



(63) 0.32 c.c. gas from 1 gr. CuO heated for 1 hour contained 18 per cent oxygen. 



(64) 0.34 " " " " 15 



Average 1*3.5 per cent oxygen. 



(74) 0.48 c.c. gas from 1 gr. CuO heated for 2 hours contained 12 per cent oxygen. 



(75) 0.49 c.c. gas from 1 gr. CuO heated for 16 hours contained 6 per cent oxygen. 



Third Series: Temperature, 600°. 

 (Argentic Iodide fused easily; Lithic Chloride fused slowly.) 



(76) 0.43 c.c. gas from 1 gr. CuO heated for 10 min. contained 12 per cent oxygen. 



(77) 0.38 " " " " 12 



Average 12 per cent oxygen. 



(78) 0.46 c.c. gas from 1 gr. CuO heated for 20 min. contained 13 per cent oxygen. 



(70) 0.53 c.c. gas from 1 gr. CuO heated for 35 min. contained 10 per cent oxygen. 



(80) 0.51 " " " " 8 " 



Average 9 per cent oxygen. 



Fourth Series: Temperature, G40°. 



(Thallous Sulphate just fused ; Strontic Nitrate remained solid.) 



(81) 0.21 c.c. gas from 1 gr. CuO heated for 2 min. contained 35 per cent oxygen. 



(82) 0.19 " " " " 30 



» Average 35.5 per cent oxygen. 



