[ I 0 T 3 ] 
XLV. Observations on the Solar Eclipfe which happened' 
June 24, 1778. By Mr. William Wales, F. R. S. and 
Majler of the Royal Mathematical School in Gb rift’s 
Hofpital. 
Read J u, y 9 > r'pHE following obfervations of the folar 
1770. I 
eclipfe, which happened on the 24th 
inftant, were made at the Royal Mathematical School im 
Chrift’s Hofpital, where the latitude is 51 0 30' 55" N. 
and the longitude not quite half a fecond in time Weft of 
the cupola of St. Paul’s. I had my time by a- mroft excel- 
lent watch made by Mr. larcum kendall, which goes 
while it is winding up, and has a provilion for counter- 
acting the effeCts of heat and cold. It was regulated by 
double altitudes of the Sun’s lower limb, taken from a 
bafon of quickiilver with a Hadley’s quadrant of Mr. 
ramsden’s making; and the quickiilver was fhaded from 
the wind by a roof, formed by two glaffes whofe planes 
had been ground perfectly parallel by the fame inge- 
nious artift, fo that the time may, I think, be depended 
on within a fecond, or two feconds at the molt. 
My telefcope, which is of the Gregorian form, was- 
made by the late Mr. short; the focal length of the 
great fpeculum being 18 inches, and the aperture 41- 
inches.. 
