228 Analyses of Books. [Serr. 
which were communicated to him by accurate observers, con- 
stitute the ninth memoir in this collection. Considering the 
number of good observers who must have witnessed this inte- 
resting phenomenon, the number and importance of the commu- 
nications is not so great as Mr. Baily had reason to expect; 
more especially, we may be allowed to add, considering the very 
scientific and impressive manner in which astronomers had been 
awakened to the occurrence, by the extensive gratuitous circula- 
tion of a dissertation on that eclipse, printed for that very purpose 
by Mr. Baily: an example of disinterested exertion, at once 
honourable to the author and to science. According to Mr- 
Baily’s observations made at Kentish Town, north latitude 
51° 33’ 34”, and west longitude 35”:2 in time, the beginning 
was 0 21’ 42”-4, the end 3" 13’ 41”*1 (mean time at the place), 
and the duration, therefore, 2" 51’ 58’°7. The apparent diame- 
ter of the moon, and the distance of the borders of the sun and 
moon, were measured with great accuracy ; and the steps taken 
for measuring, as well as for correction, are very clearly dis- 
played. A barometer, with a thermometer within and without, 
were also noticed during the progress of the eclipse, but without 
observing any alteration in either of them. The diminution of 
light he states to have been very trifling; by no means so great 
as in the eclipse which occurred Noy, 1816, although only -78 of 
the sun’s disc was then obscured, and 87 on the occasion now 
adverted to. Venus was seen, however, by thousands of spec- 
tators with the naked eye, and Mars was visible to many. We 
pass over the observations of Mr. Dollond, Mr. Groombridge, and 
Dr. Pearson, which do not convey any new or curious informa- 
tion on the subject, to insert those of Mr. Wiseman, of Norwich, 
which are both new and curious. After stating that, according 
to Mr. Wiseman, the eclipse began at Norwich (north latitude 
52° 38’, east long. 5’ 10” in time from Greenwich), at 0" 28’ 45”, 
and ended at 3" 21’ 40”, Mr. Baily thus continues the narrative : 
“« This gentleman has also sent me the result of some experiments 
on the power of the burning lens on different substances, dur- 
ing the time of the eclipse. Having procured a piece of paste- 
board, he affixed thereto four equal pieces of different coloured 
cloths ; viz. black, blue, yellow, and red ; and placed them suc- 
cessively in the focus of a burning lens on the day preceding the 
eclipse. The following are the periods at which they respect- 
ively took fire : viz. 
Black in seven seconds. 
Blue in seven seconds. 
Red in eight seconds. 
Yellow in sixteen seconds. 
He also, on the same day, submitted the bulb of a thermome- 
ter (which then stood at 66°) to the focus of the lens ; andin 14 
minute it rose to 94°, and probably would have risen higher, had 
