THE SMALLEST PARTICLES OF MATTER 39 



10 Science, Oct. 25th, 1946. 



"See Physical Review, Jan. 15th and Feb. 15th, 1939. 



12 "A General Account of the Development of Methods of Using Atomic Energy 



for Military Purposes," (Princeton Univ. Press, 1945). 



12a Lorentz, equation is 



mo 

 m =- 



1- 



a 



where m is the mass of the moving electron, m Q its mass when at rest, v its velocity, 

 and c the velocity of light in a vacuum. 



13 In Nature, Nov. 1913, F. Soddy suggested that while the principle of relativity 

 indicates that relative velocities greater than that of light are physically impossible, 

 yet there is an actual possibility of observing in nature a relative velocity con- 

 siderably greater. Thus if two /3-particles are shot out by a radioactive body in 

 opposite directions, each with a velocity nine-tenths that of light, their actual 

 relative velocities would be 1.8c. Regarding this E. Cunningham ("Relativity and 

 the Electron Theory," Longmans, Green & Co., London, 1915) states (p. 40): "This 

 is quite true, and the principle of relativity has nothing to say against it. The 

 principle maintains that a velocity greater than c relative to the observer cannot be 

 observed. . . . The position is not that velocities greater than c are not conceivable, 

 but that real bodies become illusory in observation if they are conceived to be 

 moving faster than light. We shall also see later that the electrical constitution of 

 matter seems to indicate that a body would suffer dissolution if it were accelerated 

 so that its velocity were made greater than c." 



14 Enc. Brit., 11th ed., 1910. 



15 One of his addresses on this topic appeared in Science, 1899, 9, 666-74, 704-11. 



16 Science, 1899, 9, 889-901, and 10, 11-18. 



17 Astrophysical Jour., 1940, 92, 118. 



18 The late Dr. W. S. Andrews (General Electric Co.) published in Scientific 

 Monthly, Dec, 1928, 27, pp. 535-8, a paper entitled: "Hypon — A Hypothetical 

 Element and a Possible Source of Stellar Energy," in which he suggested the 

 possibility that what astronomers call novae are due to the sudden and terrific 

 explosion of "hypon," mass 118. He gave the following table, showing the 

 position of this hypothetical "element," which we would now speak of as 

 "transuranic": 



Helium 2(F) 2 



Neon 2(l 2 +2 2 ) 10 



Argon 2(l 2 +2 2 +2 2 ) 18 



Krypton 2(1 2 + 2 2 +2 2 +3 2 ) 36 



Xenon 2(l 2 +2 2 +2 2 +3 2 +3 2 ) 54 



Radon 2(l 2 +2 2 +2 2 + 3 2 +3 2 +4 2 ) 86 



"Hypon" 2(l 2 +2 2 +2 2 +3 2 +3 2 +4 2 +4 2 ) 118 



19 Astrophysical Jour., 1939, 90, 675-88. 



20 C. S. von Weizsaker (Astrophysical Journal, March, 1945) proposed a different 

 hypothesis, and still others are discussed in "The Observatory" for August, 1945. 

 Evidently there is no agreement as to the mode of origin of the solar system. 



21 Bull. Geological Soc. of America, April 1, 1941, pp. 562-99. 



22 Since ^UI 238 , ^AcV^ 33 , and ^Th 232 are continuously degenerating at constant 

 speed into ^Pb 206 , gaPb 207 , and ^Pb 208 , with the respective liberation of 8, 7, and 6 

 helium nuclei, geophysicists use an "age equation" of the following form: 



Amount of disintegration product 



Affe — — — — 



Rate of production of disintegration product 



