890 Dr. A. C. Crehore on 



analogy with Li one may suppose that two isotopes of Gl 

 are as in fig. 1, Gil and ; G13, both being based upon a 

 square instead of a triangle form. This, however, makes 

 the masses 9 and 9 J, the latter being a value with a large 

 fraction. If the positive charges of three units in this 

 form are changed into two twos and two fours, two 

 hydrogen atoms being on one diagonal and two alpha 

 particles on the other, as in Gl 2 fig. 1, the mass is 10*016 

 instead of 91. These three forms are shown tentatively 

 for Gl. 



The atom of boron * is known to have two isotopes of 

 masses 10 and 11 respectively. The form, B-No. 2, of 

 mass 11 is obtained by the addition of one alpha particle 

 and two equatorial electrons to the second isotope of Li, 

 giving the mass 7 + 4 = 11. 



There is an opportunity to add two more such alpha 

 particles and connecting electrons around the Li-No. 2 

 hexagon. The addition of one makes the mass 15, and 

 corresponds to no known element, but the addition of two 

 makes the mass 19 and is represented by the very sym- 

 metrical assemblage shown at F fig. 1, as fluorine. There 

 are no isotopes of fluorine as yet found. 



A possible configuration for boron is shown as B-No. 1 

 in fig. 1, consisting of the Li hexagon to which three 

 hydrogen atoms are attached, thus forming a very sym- 

 metrical figure of mass 10*024. 



In this connexion it is interesting to note that nitrogen 

 and these less stable isotopes of boron and glucinum are the 

 only atoms shown in fig. 1 that have hydrogen as one con- 

 stituent. Rutherford has succeeded in obtaining hydrogen 

 from nitrogen in the gaseous form ; but, in trying several 

 compounds of nitrogen in the solid form, he noted that 

 boron nitride and para-cyanogen gave between 1*5 and 

 2 times the number of hydrogen atoms to be expected. The 

 experimental result is in agreement with the supposition 

 that hydrogen may have been obtained from this isotope 

 No. 1 of boron, as has been recognized by Rutherford, who 

 says : " In the case of boron nitride there is also the un- 

 certainty whether boron itself emits H atoms." According 

 to this form of model the question is answered in the 

 affirmative, that boron does contain hydrogen. 



The atom of carbon takes a very symmetrical form, con- 

 sisting of a ring of 9 having three positive units of four 

 each in equilateral triangle formation. The mass is thus 

 exactly 12, there being no isotopes; but an important 



* Loc. cit. 



