Page:Philosophical Transactions - Volume 037.djvu/29

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End of the Whale-bone was fixed a Ball of Cork of about an Inch and quarter Diameter; then the great End of the Rod being inferred in the Tube, the Leaf-Brass laid on the Table, and the Tube excited, the Ball attracted the Leaf-Brass to the Hight of about three Inches by Estimation. With several Pieces of Spanish Cane and Fir-Sticks I afterwards made a Rod, which, together with the Tube, was somewhat more than eighteen Feet long, which was the greatest Length I could conveniently use in my Chamber, and found the Attraction very nearly, if not altogether as strong, as when the Ball was placed on shorter Rods. Thus far I proceeded before I went into the Country, which I did the 2d of May, 1729, taking with me several Glass Canes, and such other Materials I thought would be necessary, and could not well be procured there. I shall now give an Account of the Experiments I then made, some of which were made at Norton-Court near Feversham in Kent, at my honoured Friend's John Godfrey's, Esq; the other at Otterden-Place, at my honoured Friend's Granvil Wheler's, Esq; a worthy Member of the Royal Society, with whom I have had the Honour to be lately acquainted. I shall set down each Experiment in the Order of the Time and Place they were made, as I find it in my Notes.

The first Experiment was made at Norton-Court, May 14th, 1729, between six and seven o'Clock in the Evening. Having provided a Rod of about twenty-four Feet, that consisted of a Fir-Pole, of Cane, and the Top of Reed, upon the End of which the Ball of Cork was placed, and the great End of the Rod put into the Tube about seven or eight Inches; then theLeaf-