440 Miscellaneous Intelligence. 
years to rise above the curve or fall below it. The same laws doubtless 
operate in North America, producing a similar gradual increase, and 
subsequent decrease of mean heat, in a series of years, though the 
1844, according to Mr. Glaisher’s diagram, and will reach its minimum 
in 1851. It can be stated only asa conjecture, though by no means 
an improbable one, that Sir John Franklin entered Lancaster Sound at 
ithe close of a-group of warm years,-when the ice was in the most 
favorable condition of diminution, and that since then the annual heat 
has attained its minimum, probably in 1847 or 1848, and may now be 
increasing again. At all events, it is conceivable that, having: pushed 
on boldly im one of the last of the favorable years of the cycle, the 
ice, produced in the unfavorable ones which followed, has shut him in, 
and been found insurmountable ; but there remains the hope that if this 
be the period of the rise of the mean heat in that quarter, the zealous 
and enterprising officers now on his track will not encounter obstrucs 
tions equal to those which prevented their skillful and no less enter- 
prising and zealous predecessor in the search from carrying his ships 
beyond Cape Leopold.”—Sir John Richardso 
. Fer 
ond., Edinb. and Dublin Phil. Mag., March, 
1852, p. 232.)—The author was one of the numerous band of observers 
who planted themselves within the moon’s shadow upon the day above 
mentioned. His place of observation was Karlskrona in Sweden. He 
traces t ubt and mystery which have hitherto enveloped the phe- 
nomena attendant upon solar eclipses, to the fact, that they were observed 
ely by astronomers, and not by physicisis. This remark appears to 
be scarcely applicable where such men as Prof i . 
cerned. Surely the man whose investigations on optics have won him 
. Grounding his views on the t f ; 
author Is to show that the corona, the colored light, and the red projec 
tainly evinces considerable ingenuity anda patient study of the phe- 
nomena, are as follows:— i 
he corona observed from the absolute shadow of the moon owes 1S 
existence to the diffraction of the sun’s rays at the moon’s edge- 
