[Proc. Koy. Soc. Victoria, 30 (N.S.), Pt. II., 1918]. 



Art. XII. — Magnetic Deflection of fi-Rays: Tabulation of v 

 against RH assuming Lorentz Theory. 



By miss N. C. B. ALLEN, B.Sc. 



(Communicated by Professor T. H. Laby, M.A.). 

 [Read 8th November, 1917]. 



The negative electron, when it possesses a velocity v cms/sec, is 

 •deflected by a uniform magnetic field, H gauss, at right angles to 

 its direction of motion, into a circular path of radius R cms. such 

 that RH = vw/e, m grams being the transverse mass of the nega- 

 tive electron for a velocity v cms/sec. rn = nif,(f)(f3), where ^ = v/V, 

 V crns/sec Ijeing the velocity of light. In experiments on cathode 

 and (3 rays it is frequently necessary to calculate the velocity of the 

 rays when RH is known. Since e/nif, is now well known, and 

 Lorentz' s theory that mz=:mjl — fS')"- has teen confirmed by 

 Bucherer, it is convenient to tabulate v with RH as argument. 



The following values for e/Wg have been obtained by different 

 observers : — 



Bucher 1908 ... 1.763 x lO'E.M.U.gm-i 



Classen 1908 ... 1.776 



Wolz 1909 ... 1.767 



Lerp 1911 ... L72 



Malassez 1911 ... 1.769 



Bestelmeyer 1911 ... 1.75 



Bestelmeyer 1911 ... 1.766 



Alberti 1912 ... 1.756 



Jones 19U ... 1.75 



From a consideration of these the value 1.763 x 10^ was chosen 

 for e/m^. The velocity of light w^as taken as 2.9986x10^0 cms/ 

 sec. 



The table expresses RH in gauss-cms and v in 108 cms/sec. 

 Example: If RH=:2315 gauss-cms. then v = 241.64xl08 cms. /sec. 



