A. M. Mayer— Floating Magnets. 251 
Quaternaries. 
34) = dh sa 40 (134+13)+14 47 = (18+14)+15 
35a = (9+12)4+14... 41 = (134+138)415 © 48 8 RATSERY 
35b = (10+12)+13 42 = (13+14)+15 49 = (18+15)+16 
36 = (104+12)+14 43 = (154+14)+14 50 = (8+11+15)+16 
37 = (104+13)4+14 = (154+14)+15 5la= (8+12415)+16 
38 =(11+13)4+14 45 = (164+14)4+15 
39 =(114+13)+15 46 = (18+14)+14 
Quinaries. 
516 = (9+12+14)+16 
I do not say that the above list contains all the possible com- 
binations. 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 con- 
taining 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. 
T have stated that 19d begins the tertiaries. This is an 
unstable configuration, and is formed of 9 surrounded by 10 
magnets. The other 19, 19a, is stable, and is formed of 8a 
surrounded by 11 magnets. It is to be remarked that not 
quaternaries, etc.), even a knock on the table is sufficient to 
cause the needles of the unstable configuration to move to 
positions of stable equilibrium. 
n lookiug at the diagrams it will be observed that only the 
sable primaries form the nuclei of the secondaries, and, more- 
over, those primaries which are not dimorphous, like 2, 3, 4 
and 7, serve as nuclei to more than one secondary. Thus, 2 is 
the nucleus of 8a, 8b, 8c, 9 and 10b: 3 is the nucleus of 10a 
and 11; and 7 is the nucleus to 16, 17 and 18; while each of 
the other stable and dimorphous primaries, 5a, 6a and 8a, 
