A 602

A601. Small Spectroscope. Suitable for telescope from 3 to 6 in. aperture. The collimator and observing telescope have an aperture of 25 mm., focus of 200 mm. Both are fitted with rack and pinion. The spectroscope may be used with a grating or a 60 degree prism, and for this purpose has openings for the telescopes at the proper angles. A position circle of 75 mm. diameter, reading to degrees, is fitted to the instrument. The slit has micrometer head.

Price, without grating, but including 60 degree prism$75.00

Note.—This spectroscope can also be used on a support for laboratory work.

Support for above spectroscope. Price$4.50

A602. Spectroscope for telescopes from 6 in. to 18 in. aperture and detailed description on application.

A 701