310 PHILOSOPHICAL TRANSACTIONS. [aNNO 1739, 



Exper. 4. Mr. W. suspended afterwards 2, 3, 4, and 5 blue silk strings by 

 loops, on one cross blue silk, and found the several experiments succeed in the 

 same manner as in threads ; except that they remained a longer time before 

 they appeared in a state of repulsion, receded from one another more slowly, 

 and continued much longer in the repulsive state, after the tube was re- 

 moved. 



Exper 5. This done, he made several experiments, by mixing silks of dif- 

 ferent colours, and silks and threads of different colours, and suspended them 

 by turns on silks of different colours ; whence arose several different phaeno- 

 mena. On suspending two black silks at the before-mentioned distances from 

 each other, on a scarlet cross silk, they not only opened and receded from each 

 other at the bottom considerably, but when the tube was held under, ran or 

 jumped away from each other, to the very ends of the cross red silk that sup- 

 ported them, taking 2, 3, or more jumps from each other. The same was 

 observed of two white silks suspended on red silk, but they did not move away 

 so briskly as the black. 



Exper. 6. Mr. W. tried whether threads hanging parallel as above, from a 

 cross blue silk line, and joined with one or more transverse threads, so that 

 the perpendicular threads remained nearly parallel, would mutually repel when 

 the tube was held over them ; and they seemed to repel each other full as 

 strongly as before. When they were joined by only one cross thread towards 

 the top, the lower parts separated considerably ; when joined by two cross 

 threads, one towards the top, and one towards the bottom, they separated 

 both in the middle parts between the two cross threads, and at their lower ends 

 under the second or lowest cross thread. When several were tied together at 

 the top and bottom, and about a foot long, not by transverse threads, but in a 

 knot at each end, they all bellied out from one another, describing a figure 

 generated by an ellipsis, revolved about its greater axis ; approaching nearer to 

 a sphere, the stronger the repulsive force was. And though it was only a ne- 

 cessary consequence, he could not without some pleasure observe the knot at 

 the bottom, as the strings swelled out, sensibly rising up. He could scarcely 

 forbear imagining the bundle of silks, a bundle of muscular fibres. 



Exper. 7. He suspended two brass, and afterwards two iron wires on a 

 cross blue silk, in the same manner as the threads and silks before mentioned, 

 and found the experiments succeed as in threads of the same number, except that 

 they did not recede so far from one another, which must necessarily follow from 

 their greater weight. 



N. B. These experiments were n)ade sometimes with the tube held over. 



