Connective Cooling of Wires. 337 



diameter of Ayrton and Kilgour's smallest wire. Values 

 with radiation eliminated are plotted in fig. 1. 



(D) Kennelly * investigated the heat losses from wires in 

 very large enclosures at various pressures, thus introducing 

 another experimental variable. 



Fiff. 1. 



^ 



X 



-J 



© 



A 







B 



&' 



C 



X 



D 















E 



F 



o 



n 







■og 



9d7/ 



5 



Langmuirf has corrected these for radiation, and his 

 corrected values have been used in compiling Table III. 

 The points, if plotted on fig. 1, are in excellent agreement, 

 but to preserve a clear figure only two points are shown, 

 these corresponding to the extremities of the range. 



(E, F, (fc Gr) Petavel J, who worked over a wide range of 

 pressure (1/10 to 100 atm.) and up to 1100° C. excess, has 

 given data by means of which the performance of different 



* Kennellv, Trans. A.I.E.E. xxviii. (1) p. 363 (1909). 

 t Langmuir, Trans. A.I.E.E. xxxi. (1) p. 1228 (1912). 

 % Petavel, Phil. Trans. A, cxcvii. p. 229 (1901). 



Phil. Mag. S. 6. Vol. 43. No. 254. Feb. 1922. Z 



