164 Curious Effect of Solar Light. 
on a small stream, iu a calm night, when no wind or moving 
object disturbs the water; at the same time great care must 
taken to keep the water at the same altitude, and the wheel 
with uniform friction. But there is an important circum- 
stance in his case, which must have rendered his experiment 
incomplete. This is, that he discontinued his observations 
at 12 o’clock. But the greatest acceleration of the wheel is 
not till the break of day. My observations, made in 1799, 
were conducted with great care, from sun-set to sun-rise, and 
these gave an acceleration of one-ninth—the wheel making © 
16 revolutions at sun-set, and 18 at day-break. See my His- 
tory of Pestilential Diseases, vol. II. p. 298, Am. edit. 
N. WEBSTER. 
New-Haven, Nov. 1826. 
IX. Curious effect of Solar Light ; communicated in aletter 
dated Berlin, Conn. Feb. 22, 1826, to Dr. Cas. HoOKER-— 
Last week (Feb. 13, 1826) I observed a rather singular meteo- 
rological phenomenen, whicl had att 
fo 
its point of divergence, or centre, was below the horizon, 
apparently as many degrees below as the sun was above.— 
= -greatly—by 10 o’clock it had condensed into a uniform s¢ra- 
: ese a 8 o’clock next morning a storm came on from t 
‘the mountains covered with fog—by noon the wind 
aki. 
