SCIENTIFIC SUMMARY. 
193 
the January number of the Popular Science Review, more detailed ac- 
counts have been received from abroad of the periodic meteor shower of 
November last. Professor Daniel Kirkwood, of Bloomington, Indiana, in 
spite of the hazy state of the atmosphere, which obscured all stars but those 
of the first magnitude, observed 526 meteors in eight hours. Commander 
Chimmo, of H. M. S. Gminet, at five in the morning of November 14, when 
rounding the north point of Martinique, saw an immense number of bright 
sparks falling into the sea, with occasionally a meteor of large size bursting 
and lighting up the whole heavens. The same observer states that the 
shower was more distinctly seen at Trinidad, where, on the same morning, 
from two o’clock to daybreak, 1,600 meteors were counted, and about eight 
per cent, were thought to have been missed. At Nassau, Bahamas, Captain 
Stuart and other observers counted about 1,100 meteors between 2h. 30m. 
and 4h. 45m. on the morning of the 14th, but only a portion of the sky was 
noticed. At the Cape of Good Hope, Mr. G. W. H. Maclear observed the fol- 
lowing meteors: — On the night of November 12th, 3 meteors; 13th, 9 meteors ; 
14th, 17 meteors, principally from Leo ; 15th, 5 meteors. At the meeting of 
the Astronomical Society in February last, Mr. Pritchard said that, although 
the meteors were not seen in this country, the accounts coming in from 
America prove that the display was little, if at all, inferior to that of 1866. 
The orbit of these meteors had been investigated by Professor Adams, who 
has shown that Professor Newton’s period of 354*6 days, and his other 
shorter periods, fail to satisfy the motion of the node, and that the meteors 
have undoubtedly a period of 33|^ years. 
The Planet Mars . — To determine with greater exactness the period of 
rotation of this planet, which is interesting to us as being not only the 
nearest to the earth, but, as far as we have means of judging, bearing the 
gi'eatest resemblance to our globe, is a problem which Mr. Proctor has lately 
set himself. Taking advantage of the views made by Mr. Browning in 
January and February 1867, he has estimated the rotation-period by means 
of an interval of nearly 201 years. From the results of the calculation of 
three long periods, viz. from March 12, 1666, 12h. 20m. (astronomical time 
and new' style), to April 24, 1866, November 26, 1864, and February 23, 
1867 respectively, Mr. Proctor deduces the rotation of the planet as taking 
place in 24 hours 37 minutes and 22*735 seconds. 
Heat given out hy the Moon . — The influence of the moon upon the weather 
has been a disputed point from the earliest times. By some it has been 
entirely denied, while others have attached to it an importance apparently 
insulficiently founded on experience. Our readers will, therefore, be glad 
to hear that some facts relative to the heat given out by our satellite have 
lately been brought before the Astronomical Society in a tangible shape by 
Mr. J. P. Harrison, from which further observation may possibly deduce 
very valuable results. In his paper on the subject, Mr. Harrison shows that 
the heat acquired by the moon from the sun, and radiated to the earth, is 
what Professor Tyndall calls dark heat,” or what wmuld be almost 
wholly absorbed by our atmospheric vapour. This w-ould raise the tempera- 
ture of the air above the clouds, increase evaporation from their surface, and 
diminish their density, raise them to a higher elevation, and, imder favour- 
able circumstances, disperse them. In either case a sensible fall would take 
