78 Chronicles of Science. [Jan., 
delivering its contents sweet at the end of a journey of sixty miles 
in summer time. And although it appears at first as if it were wiser 
to carry fifteen or twenty pounds of milk from the farm to the town 
than to carry the hundredweight of food out of which it is made as 
far to a cowhouse in the town, yet dealers in milk will give so much 
more for the townshed milk than for the country milk, that there 
is a great profit and advantage to all concerned in carrying the 
larger weight, though it-be of course at a greater cost. 
II. ASTRONOMY. 
Tur President of the Astronomical Society, Warren De la Rue, 
F.RS., has communicated some observations of the partial eclipse of 
the moon, of October 4, 1865. On the occasion of a former partial 
eclipse—viz. that of February 27th, 1858—several photographs 
were obtained of the moon, and he was led to suspect the existence 
of an anti-actinic influence extending beyond the limits assignable to 
the penumbra. To ascertain whether any such influence really 
exists was the principal object on the present occasion. Operations 
were, therefore, commenced some little time previous to the first 
contact of the penumbra; and the night at Cranford being very 
bright, and the atmosphere tolerably steady, photographs of the 
moon were obtained with an exposure of from one to three seconds, 
using for that purpose Steinheil’s silvered glass mirror of 13 inches 
aperture and 10 feet local length; the action of which however 
was not more rapid than that of the speculum-metal mirrors (of the 
same dimensions and focal length), which had been hitherto chiefly 
used in celestial photography. After contact, it was found that 
an instantaneous exposure sufficed to give a faint impression of 
that portion of the lunar disk not obscured by the umbra, or 
penumbra, an exposure of a whole minute failed to bring out 
the portion of the lunar surface covered by the umbra, although 
its details were plainly perceptible in the telescope. The obscured 
portion of the moon was, moreover, perfectly visible without optical 
aid. ‘To the naked eye, and even in the finder, the dark limb 
of the moon appeared to be bounded by a silvery thread of 
light ; but this illusion disappeared under powers of 90 and 140, 
both in the reflector and in 4 1-8th inch Dallmeyer. The umbra 
towards the moon’s limb had a coppery glow, while that towards 
the penumbra was of an ashy grey colour. The penumbra could be 
much better traced when the image was projected on a screen 
placed in the focus of the reflector than when viewed directly 
through the eye-piece ; and probably—though this experiment was 
not tried—the projection of an enlarged image of the penumbra by 
