298 Professor Dewar on the 



obtained as a bye-result the average approximate value 



/* = 385. 



A recalculation of this value, however, shows an arithmetical 

 error, which multiplies the value by 4, so that the true ap- 

 proximate value yielded by the data is /u, = 96, ranging between 

 the values 107 and 83*5, the extremes of the three values. 

 These are lower than the results given by Klemencic, but in 

 my experiments the rate of oscillation was much higher. 



In this connexion it is interesting to note that Mr. Oliver 

 Heaviside, in his ' Electrical Papers,' vol. i. p. 361, u Waves 

 of Magnetic Force/'' remarks that fi is eminently variable, 

 but that a fair average value is fi=100. This assumption 

 seems confirmed both from Klemencic' s results and my own. 



I am, Gentlemen, 



Yours respectfully, 



Chaeles E. St. John. 



Berlin, Jan. 10, 1895. 



XXIX. On the Liquefaction of Gases. 

 jfy Prof. J. JDewak*. 



IN the Philosophical Magazine for last month Professor 

 Olszewski has made serious allegations regarding my 

 relations to his alleged discoveries. It is usually assumed 

 that if a scientific man has a grievance on some question of 

 priority, he speaks out boldly at or about the time when 

 his discovery is being appropriated. It seems, however, that 

 Professor Olszewski prefers to nurse his complaints for four 

 years and then to bring them out simultaneously in two 

 English scientific journals. The result, I am afraid, will be 

 grievously disappointing. Personally I am delighted to see 

 an English edition of Professor Olszewski's papers. There 

 is, however, one serious omission which I trust the Editors 

 of the Philosophical Magazine may remove before long. We 

 want in this country a reprint of the splendid papers of 

 the late Professor Wroblewski. Until this is done it will be 

 impossible for the scientific public to decide on many of 

 Professor Olszewski's claims for priority. Now let me turn 

 to the Professor's treatment of myself. The following are 

 the deliberate statements made by him in his paper u On the 

 Liquefaction of Gases," Philosophical Magazine, February 

 1895 :— 



* Communicated bv the Author. 



