• If? 



170 DR. FARADAY ON THE LIQUEFACTION AND SOLIDIFICATION OF 



The following is a table of the pressure of ammonia vapour, the marked results, as 

 before, being those obtained by experiment : — 



Atmospheres. 



. 7-00 



. 7*50 



. 7*63 



. 8-00 



. 8-50 



. 9-00 



. 9-50 



. 10-00 



. 10-30 



Jrseniuretted Hydrogen. — This body, liquefied by Dumas and Soubeiran, did not 

 solidify at the lowest temperature to which I could submit it, i. e. not at 166° below 

 0°Fahr. In the following table of the elasticity of its vapour the marked results are 

 experimental, and the others interpolated : — 



Fahr. 

 --7°5 



-70 



- — 64 



— 60 



- — 52 



— 50 



— 40 



- — 36 



Atmospheres. 



0-94 



1-08 



1-26 



1-40 



1-73 

 1-80 



2-28 

 2-50 



Fahh. 



o 



— 30 



--23 



-20 



-10 



-— 5 







3 



Atmospheres 



. 2-84 



. 3-32 



. 3-51 



. 4-30 



. 4-74 



. 5-21 



. 5-56 



Fahh. 

 -10 

 -20 

 30 

 -32 

 -40 

 -50 

 -60 



Atmospheres. 



6-24 



7*39 



8-66 



8-95, 



10-05 



11*56 



13-19 



The following bodies would not freeze at the very low temperature of the carbonic 

 acid bath in fac2<o (—166° Fahr.) : — Chlorine, ether, alcohol, sulphuret of carbon, 

 caoutchoucine, camphine or rectified oil of turpentine. The alcohol, caoutchoucine, 

 and camphine lost fluidity and thickened somewhat at —106°, and still more at the 

 lower temperature of — 166°. The alcohol then poured from side to side like an oil. 



Dry yellow fluid nitrous acid when cooled below 0° loses the greater part of its 

 colour, and then fuses into a white, crystalline, brittle and but slightly translucent 

 substance, which fuses a little above 0°Fahr. The green and probably hydrated 

 acid required a much lower temperature for its solidification, and then became a pale 

 bluish solid. There were then evidently two bodies, the dry acid which froze out 

 first, and then the hydrate, which requires at least —30° below 0° before it will 

 solidify. 



