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POPULAR SCIENCE REVIEW. 
examining the phase-curve which had been obtained, a certain 
want of symmetry on the two sides of full Moon was perceived, which was 
ascribed to the unequal distribution of mountain and plain on the lunar 
surface, as was shown by a rough diagram of the lunar surface with its so- 
called ^seas.’ It had also been found that the percentage of the Moon’s 
heat transmitted by a sheet of glass diminished from 17-3 per cent at full 
Moon to about 13*3 per cent, at 22^°, 11 per cent, at 45°, and 10 per cent, 
at 67^°, distance from full Moon; a circumstance which might have been 
accounted for by supposing that there is a constant amount of radiant heat 
coming from the Moon in addition to that which, like the light, varies with 
the phase, had it not been found that as the Moon approached tolerably 
near the Sun — as for instance, on March 27, 1871, when her distance from 
full was 138° — no perceptible amount of heat radiated from her surface. 
The less rapid decrease of the Moon’s heat than of her light on going 
farther from full Moon, and the increase of percentage of heat transmitted 
by glass towards the time of full Moon, may probably be explained on the 
assumption that when the Sun’s heat and light strike the Moon’s surface 
the whole of the former and only a certain proportion of the latter, depend- 
ing on the intrinsic reflecting power or ‘ Albedo ’ of the surface, leave it 
again, and consequently the shaded portions, which are inclined more 
towards the position of the Earth at quadratm’e than at full Moon, reflect 
a larger amount of heat as compared with the light of the former than at 
the latter time, and a greater flatness of the heat- than of the light- phase 
curve is the result. With a view of obtaining a decisive result on the ques- 
tion, whether or not the Moon’s surface requires an appreciable time to 
acquire the temperatures due to the various amounts of radiant heat falling 
on it at different moments, simultaneous determinations of the amount of 
the Moon’s heat and of her light were made, whenever the state of the sky 
allowed of it, during the eclipse of Noy. 14, 1872. The eclipse was a 
very partial one, only about ~ of the Moon’s diameter being in shadow ; 
but although this circumstance, coupled with the uncertain state of the 
sky, rendered the observation far less satisfactory than it would otherwise 
have been, yet it was sufficient to show that the decline of light and heat 
as the penumbra came over the lunar surface and their increase after the 
middle of the eclipse were sensibly proportional. Both were reduced to 
about one half- what they were before the eclipse.” 
The Transit of Venus in 1882. — Mr. Proctor has supplied a stereographic 
chart illustrative of the transit of 1882, and intended specially for com- 
parison with the corresponding chart of the transit of 1874, supplied by 
him a month earlier. He remarks that it is very desirable, in considering 
what preparations should be made for observing the transit of 1874, to take 
carefully into account the relations which will be presented during the 
transit of 1882. To neglect this precaution,” he says, “ would be as 
serious a mistake as for one nation to arrange its plans for either transit 
without a careful reference to the arrangements of other nations. It has 
been with the object of supplying this want that I have constructed the 
accompanying chart of the transit of 1882 ; for although the circumstances 
of the latter transit have been to some degree considered (by myself amongst 
other students of the subject), I do not think they have as yet been suffi- 
