30 inch Speculum, with 12 powers and position
micrometer, and transit eye-pieces 1000 0 0
Prices will be forwarded for special arrangements in any of these
large sizes.
The CASSEGRAIN TELESCOPE is a very convenient form, and perfect in
performance, and in this form a very large instrument requires
comparatively a much smaller observatory, and is more conveniently
worked. They can be made so that the image is thrown out at the side
and viewed diagonally, as with the Newtonian, see p. 35. Cassegrains
from 5 per cent. extra.
£ s. d.
Driving Clocks for 6 to 10 inch 35 0 0
〃 〃 12 〃 18 〃 40 0 0
〃 〃 20 〃 30 〃 50 0 0
The EDUCATIONAL REFLECTOR is a plain and very steady and
satisfactory instrument, mounted on (Fig. 2) stand, without circles,
has revolving body, and made so as to be portable.
£ s. d.
6-1/2 inch Speculum (clear aperture), and of 4 to
6-1/2 feet focus, has screw-motion in right ascension,
2 powers 25 0 0