A. M. Mayer—Floating Magnets. 255 
An advantage of this form of the experiment is that the con- 
figuration can be transported, and may thus serve in illustration 
of a moviug molecule as is set forth in the kinetic theory of 
7 ses. It is interesting to watch the mutual actions of two or 
more approaching configurations, and to observe the motions 
in the exterior and in the contour of a suspended configuration 
. on its impact against a resisting or a yielding surface. 
| Professor O. N. Rood suggested to me to replace the sus- 
pended magnets by gilded pith balls, hung by silk fibers and 
similarly electrified. 
| Professor Frederick Guthrie, of London, under date of May 
21, writes: “If the corks are made somewhat wider than in 
magnets about # inch in length. Run each of these through a 
thin section of a small cork and then coat both needle and cork 
