70 
leave to future times monuments by which the secular changes 
of the moon’s physical aspect may be determined. And if this 
be impracticable— if the utmost success of the photographer 
should only produce a picture of the larger features of the 
moon, this will be a gift of the highest value, since it will be 
a basis, an accurate and practical foundation of the minuter 
details, which, with such aid, the artist may confidently sketch.” 
The pictures of the moon taken by Professor Phillips were 
made with a six and a-quarter inch refractor by Cooke. It 
is of eleven feet focus, and produces a negative of one and a- 
quarter inches diameter, in thirty seconds. Professor Phillips 
does not enter very minutely into the photographic part of 
the subject, but he gives some very useful details of calcula- 
tions as to what may be expected to be seen in photographs 
taken with such a splendid instrument as that of Lord Rosse. 
It is assumed that an image of the moon may be obtained 
direct of twelve inches diameter, and this when again magni- 
fied sufficiently would show “ black bands twelve yards 
across.” What may be done remains to be seen, but up to 
the present time the Professor’s anticipations have not been 
realised. 
We have next, from the pen of Mr. Crookes, a paper com- 
municated to the Royal Society of London, in December, 
1856, but which was not read before that society until 
February in the following year. Mr. Crookes appears to have 
obtained good results as early as 1855, and, .assisted by a 
grant from the Donation Fund of the Royal Society, he was 
enabled to give attention to the subject during the greater 
part of the year following. The details of the process em- 
ployed are given in the paper with much minuteness. The 
telescope used was the equatorial refractor at the Liverpool 
Observatory, of eight inches aperture, and twelve and a-half 
feet focal length, producing an image of the moon 1*35 inch 
diameter. The body of a small camera was fixed in the place 
of the eyepiece, so that the image of the moon was received 
