﻿280 



Mr. K. D. Kleeman on the Recombination 



The leaks were taken for 20 seconds. 



The X-ray bnlb was worked by a coil having an ordinary 

 interrupter. 



When the two chambers were disconnected from the 

 electrometer and the X-ray bulb sending out rays, there was 

 a leak of about 30 scale-divisions in 20 seconds, due to the 

 natural leak of electrometer and ionization in the connexion 

 tubing by stray X rays. This small leak appeared in the 

 leak of the adjustable chamber, but it was not subtracted 

 since its exact value was not known on account of the 

 intensity of the rays not being constant. Its value must be, 

 however, almost proportional to the total leak, and it reduces, 

 therefore, in each ratio of leaks to an approximately equal 

 quantity. The natural leak of the standard chamber, found by 

 subtracting the leak of the electrometer from that of electro- 

 meter and chamber, was very small. The disturbing effect of 

 these small leaks upon the readings must be very small, as is 

 shown by the consistent readings obtained, though the 

 induction-coil worked very irregularly, and the leak had some- 

 times to be taken for a longer or shorter time than 20 seconds. 



The following table gives some of the readings obtained 

 with the lead chambers. 



Table IV. 



Time. 



Volts 

 per cm. 



Deflexion 



(adjustable 

 chamber). 



Deflexion 

 (standard 

 chamber). 



Eatio. 



20 sec. 



5) 



1200 



8 



1200 



8 



2339 

 2405 

 2400 

 2138 



1327 

 1458 

 1339 

 1305 



176 

 165 

 179 

 163 



Lack of 

 saturation 

 8 per cent. 



20 sec. 

 12 „ 

 18 „ 

 24 ., 



20 



1200 



20 



1200 



1251 



1208 



1169 



594 



023 



587 

 586 

 291 



201 

 20() 

 200 

 204 



Lack of 

 saturation 

 2 per cent. 



The readings for the voltages 20 and 1200 were taken 

 with an X-ray bulb which had been run so hard that the 

 coil (giving a six-inch spark) was scarcely able to work it. 

 It was found at the end of these experiments that the platinum 

 of the spark-gap was almost worn away, which accounts, to 

 some extent, for the irregularity of the rays. 



General recombination could scarcely have affected the 

 above readings. The capacity of lead chamber together with 

 the electrometer was found to be about 180 E.S. Us., while 



