Intelligence and Miscellaneous Articles 75 
essay I proposed to M. Cailletet, who hastened to try it. He did 
not succeed ; but I do not despair. — Comptes Bendus de VAcademie 
des Sciences, May 21, 1883, pp. 1448-1452. 
ON THE LIQUEFACTION OF OXYGEN AND THE CONGELATION OF 
CARBON DISULPHEDE AND ALCOHOL. BY PBOFESSOES SIGM. 
VON WEOBLEWSKI AND K. OLSZEWSKI. 
The results at which Cailletet and Raoul Pictet arrived in their 
beautiful investigations on the liquefaction of gases permitted the 
hope that the time was not distant when liquid oxygen would be 
observed in a glass tube as easily as liquid carbonic acid now is. 
The only condition for this was the attainment of a sufficiently 
low temperature. In a memoir pubKshed twelve months since*, 
Cailletet recommended liquid ethylene as a means for attaining a 
very low temperature ; for the liquefied gas boils at — 105° C. under 
the pressure of the atmosphere, the temperature being measured 
with a carbon-disulphide thermometer. Cailletet himself compressed 
the oxygen in a very narrow glass tube which was cooled in that 
liquid to —105° C. At the moment of the expansion he saw "a 
tumultuous ebullition, which persists during an appreciable time 
and resembles the projection of a liquid into the cooled portion of 
the tube. This ebullition takes place at a certain distance from the 
bottom of the tube. I have not been able to ascertain," he con- 
tinues, " if this liquid preexists, or if it is formed at the moment of 
the expansion ; for I have not yet been able to see the plane of 
separation of the gas and liquid." 
As one of ust had recently constructed a new apparatus for high 
pressures, with which comparatively large quantities of gas can be 
subjected to the pressure of 200 atmospheres, we employed it to 
study the temperatures at the moment of the expansion. These 
experiments soon led to the discovery of a temperature at which 
carbon disulphide and alcohol congeal and oxygen is with great 
facility completely tiquefied. This temperature is reached when 
liquid ethylene is permitted to boil in a vacuum. The boiling-tempe- 
rature in this case depends on the goodness of the vacuum obtained. 
With the greatest rarefaction which it has hitherto been possible 
for us to attain, the temperature descended to — 136° C. This, as 
well as all the other temperatures, we measured with the hydrogen 
thermometer. 
The critical temperature of oxygen is lower than that at which 
liquid ethylene boils under the pressure of one atmosphere. The 
latter is not —105° C. (as has hitherto been assumed), but lies be- 
tween — 102° and —103° C. (as we have found with our thermo- 
meter). 
From a series of observations made by us on the 9th April of this 
* Comptes Rendus, t. xciv. pp. 1224-1226. 
t S. v. WroblewsM. 
