STANDARD - Survey Instrument Antique Center!

227
Portable Astronomical Transit Instrument.
As made for U. S. Lake Survey.
No. 17. Aperture of object-glass 3 in.; focus 39 in.; spider-line or glass micrometer; diagonal eyepiece
magnifies from 90 to 120 dia. Ramsden ; eye-piece magnifies 75 dia.; striding level reads to
seconds of arc; adjustable mirror to read the level from below; reserve level; pivots of hardened steel;
small adjustable plane reflector; two lamps and arms; reversing apparatus; two finding circles each
provided with double verniers; cast-iron frame rests on three leveling screws of steel, which are provided
with foot-plates one of them is adjustable to set instrument- in the meridian; two cases, etc.
Price $13OO.OO
(Notice of this Instrument, with full description, in Johnson's New Universal Cyclopaedia, under
article "Transit.")
The above instrument provided with an Impersonal Micrometer, U. S. C. & G. S. Pattern.
Price on application.