196

EXPERIMENTS WITH

TRACT 3G.

EXPERIMENTS OF THE YEARS 1787 and 1788.

July 31, 1737.

44. By comparing the experimented resistance on thevertex of the cone, with the theory, it appears that it isnearly equal to the resistance of the sphere; whereas, bythe received theory, it ought to be only about | of that ofthe sphere; I therefore this day tried these two bodiesagain, and found the results nearly the same as before.With the 32 oz weight, the mediums among the times of arevolution, were thus : viz,

This year they were,for the cone 2'10"for the globe 2 - 02

Last year they were2.07"

2 , 01, nearly the same.

So that it seems difficult to account for so great a differencebetween theory and experiment, in the case of the cone’svertex.

Aug. .5, 1787.

Fine, clear, warm Weather.

45. Performed experiments with the following bodies,and found the medium of the times of revolution as fol-lows.

targe

Globe

The Cone,

Sumll Hemis.

Lend of

2 oz 5 dr

vertex

base

base

conv.

2"

2-05"

to

to

2-3

16

1-6

The actuating weight was 32 oz for each figure, and 8 ozfor the thin lead weight, the same as June 30, 1786.