102 Prof. A. M. Mayer on the Laws of the 





Tertiaries. 





196 = 9 + 10 



25a =12 + 13 



29a =16 + 13 



20a = 9 + 11 



256 =13 + 12 



296 =17 + 12 



206=10 + 10 



26a =13+13 



30a =17 + 13 



21a =10 + 11 



266 =14 + 12 



306=18 + 12 



216=11 + 10 



27a =14 + 13 



31 =18 + 13 



22 =11 + 11 



276=15 + 12 



32 =18 + 14 



23 =11 + 12 



28a =15 + 13 



33 =18 + 15 



24a =12 + 12 



286 =16 + 12 



34a = (8a + 12) + 14 



246=11 + 13 









Quaternariet 





346 = (9 + 



10) + 15 43 



= (15 + 14) + 14 



35a = (9 + 



12) + 14 44 



= (15 + 14) + 15 



356 =(10 + 



12) + 13 45 



= (16 + 14) + 15 



36 =(10 + 



12) + 14 46 



= (18 + 14) + 14 



37 =(10 + 13) + 14 47 



= (18 + 14) + 15 



38 =(11 + 13) + 14 48 



= (18 + 15) + 15 



39 =(11 + 13) + 15 49 



= (18 + 15) + 16 



40 =(13 + 13) + 14 50 



= (8 + ll + 15) + 16 

 = (8 + 12 + 15) + 16 



41 =(13 + 13) + 15 51a 



42 =(13 + 



14) + 15 



Quinaries. 







516=(9 + 12 + 14) + 16. 



I do not say that the above list contains all the possible 

 combinations. The list is more for the purpose of establishing 

 the laws which I have already formulated. 



In my first publication I gave two configurations for four 

 needles : — one having the needles at the corners of a square, 

 and a stable form ; the other unstable, and formed of a triangle 

 containing a central needle. I have concluded that this form 

 does not exist; at least its existence is so transient that it has 

 never remained long enough for me to take a print of it. 



I have stated that 196 begins the tertiaries. This is an 

 unstable configuration, and is formed of 9 surrounded by 10 

 magnets. The other 19, 19 a, is stable, and is formed of 8 a 

 surrounded by 11 magnets. It is to be remarked that not 

 alone the tertiaries, but the configurations in the other classes 

 begin with an unstable group of magnets. Thus 8 c begins 

 the secondaries, 19 6 the tertiaries, 346 the quaternaries, and 

 51 6 the quinaries. 



The reader has seen that a given number of magnets may 

 form two or more different configurations. Thus five mag- 

 nets form two, 56 a square with a magnet at its centre, and 



