C 49 1 ] 
I. An Account of the Experiments made hy 
fome Ge7itle7nen of the Royal Society, in 
order to meafure the ahfolute V elocity of 
Electricity ; communicated to the Royal 
' Society by Mr • W. Watfon F.R . S> 
-R^oa.27.TLAID before the Royal Society the Be- 
i?4 8 - X ginning of laft Winter an Account * of 
what had been done by fome Gentlemen, in order 
to afeertain the refpedive Velocities of Eledricity 
and Sound ; from which it appeared, that through a 
Space meafuring 6732 Feet, the Eledricity was per- 
ceptible in a Quantity of Time lei's than ^3 of a 
Second* But the Gentlemen concerned were de- 
firous, if poffible, of afeertaining the abfolute Velo- 
city of Eledricity at a certain Diftance; and a Me- 
thod had been thought of, by which this might be 
determined with great Exadnefs. 
Accordingly, Augujl y. 1748. there met at Shooter's 
Hill for this Purpole, the Brefident of the Royal 
Society , the Rev. Mr. Birch , the Rev. Dr. Bradley , 
Aftronomer Royal, James Burrow Efq; Mri Ellicot , 
Mr. George Graham , Richard Graham Efq; the 
Rev. Mr. Lawrie , Charles Stanhoye'Efy, and myfelf, 
who were of the Royal Society , Dr. Bevis y and 
Mr. Grifchow jun. a Member of the Royal Academy 
of Sciences at Berlin. 
It was agreed to make the eledrical Circuit of 
two Miles ; in the middle of which an Obferver 
was to take in each Hand one of the Extremities of 
Ttt a 
* See thefe Tranf. N°. 485. 
