118 



It will 

 65-2, or 



measured 

 at 22. 

 In the 



DR. B. D. STEELE, DR. D. McINTOSH AND DR. E. H. ARCHIBALD 



be seen that the curve for hydrogen chloride cuts the temperature axis at 



11-9 above the critical point. 



We have not been able to find any record 

 of measurements of the critical temperature of 

 phosphuretted hydrogen. 



The Measurement of Viscosity. 



The viscosity apparatus (fig. 9) was of the 

 usual form, but with some slight additions, 

 which were designed to prevent access of water 

 vapour. For this purpose the two ends of the 

 apparatus were joined to the stop-cock h, and 

 the two tubes c and d, containing phosphoric 

 anhydride, were attached. After the apparatus 

 had been placed in the bath, a definite quantity 

 of the liquid was distilled into it through d. 



In order to make the measurements, the stop- 

 cock was closed and, by blowing into d, the 

 liquid was forced into f until it reached a 

 position about one centimetre above the mark a. 

 The stop-cock was then opened and the time 

 required for the liquid to fall from a to b 

 with a stop-watch. The apparatus was calibrated with distilled water 



tables, D refers to the density of the liquefied gas; 17 is the viscosity 



compared with that of water at 22, and -3- is the temperature coefficient of viscosity. 



ctt 



TABLE XII. Hydrogen Chloride. 

 Apparatus B. Time of flow for water = 7 5 '3 seconds at 22. 



