[ 4 °* 1 
greateft Perfection; and he did not doubt but in a 
fhort Time to be able to aftonifh the World with a 
new Sort of Planetarium never before thought of, 
and that from thefe Experiments might be eftablifhed 
a certain Theory for accounting for the Motions of the 
Grand Planetarium of the Univerfe. 
In trying thefe Experiments fince his Death, I have 
found that the fmall light Body will make Revolu- 
tions round a Body of various Shapes and Subftances, 
as well as round the Iron Globe, if fet on the Cake of 
Rolin 5 thus I tried with a Globe of black Marble, a 
Silver Sand-difh, a fmall Chip- box, and a large Cork. 
I obferved that the Cake, if nothing flood upon it, 
would in any Part ftrongly attract the light Body, as 
held fufpended by the Thread 5 but when the Globe, 
or other Body, was fet upon it, the Edges of the Cake 
attracted the ftrongeft, and fo gradually the Attraction 
Teem'd as it approached the Centre to grow lefs, till 
at a certain Diftance it was changed into a Repulfion, 
which proceeded from the Globe, or other Body 
placed upon the Cake, which very ftrongly repels the 
light Body, unlefs it be held very near it, and then it 
attrads it ftrongly. While the light Body is fufpended, 
as in the foregoing Experiments, if you approach the 
Finger of the other Hand near it, it will fly from the 
Finger, or be rebelled by it with great Vigour. 
Ff f z 
IX. Some 
