184 Mr. H. Moore on the Ionization in Carbon- 

 It is possible now, on the assumption already referred to, 

 to calculate from the ionizations observed the total cor- 

 puscular radiation liberated in each mixture by the X-ray 

 beam used, this ionization being produced by the re-ab- 

 sorption of these ejected corpuscles. Thus if the ionization 

 produced in a certain mixture (column II. Table I.) is 

 divided by the factor corresponding to that mixture as given 

 in column II. Table II., the result obtained is a measure of 

 the total corpuscular radiation liberated in the mixture by 

 the passage of the beam of X-rays ; these results are given 

 in column III. Table II. The corpuscular radiation from 

 the sides of the chamber and from the hydrogen is ob- 

 tainable from the corresponding observations on hydrogen 

 alone, hence by deducting for each mixture the corpuscular 

 radiation due to the hydrogen and from the sides, the 

 corpuscular radiation liberated from the vapour present is 

 obtained. The numbers in column IV. Table II. give the 

 amount to be deducted in each case, being calculated on 

 the assumption that this additional corpuscular radiation is 

 entirely due to the hydrogen, none coming from the ends ; 

 this is, of course, untrue, but the error due to this is no 

 larger than if it were assumed to be all from the ends, and 

 in either case is beyond the limits of experimental accuracy. 

 The corpuscular radiation liberated from the vapour alone 

 at its saturation pressure for 0° C. is given for each vapour 

 in column V. Table II. 



Insulation and other constant leaks are not corrected for 

 by this method with absolute accuracy as the '"factors" are 

 not exactly equal ; as, however, these steady leaks were 

 very small, and the " factors " are not very different from 

 unity, these leaks are still corrected for to well below the 

 limits of experimental accuracy, an important advantage of 

 this method when the total ionization leaks in some cases 

 are so very small. 



Having obtained the values for the corpuscular radiation 

 liberated from each vapour at a known pressure, the cor- 

 puscular radiation from each corresponding to a pressure of 

 76 cm. was calculated (column VI. Table II.). 



Equations were then formed, giving the numbers of atoms 

 of carbon, oxygen, and hydrogen in each compound, and 

 equating their sum to the corpuscular radiation calculated 

 as above for that compound. 



Thus, if represents the corpuscular radiation from an 

 atom of oxygen, C that from an atom of carbon, and H that 

 from an atom of hydrogen, we obtain the equations : — 



