zontal adjustment for the telescope is provided. No provision is
made for radial adjustment, which correction is made before the instrument
is sent out. The slit is accurately constructed; the jaws are of German
silver and it is provided with comparison prism. The eye end of the
observing telescope is of standard size so as to receive our micrometers
M201 or M202, or the Auto Collimating eye piece (Lamont & Abbe) M540. Gauze
eye piece is fitted to the instrument. The prism table and observing
telescope have independent movements and each is provided with clamp and
tangent screw. The prism table can be clamped to any part of the vernier
plate. The prism holder has convenient leveling arrangement and will hold
prism up to 35 mm. in height. The instrument is arranged to receive Fuess
centering apparatus and crystal holder. A 60 degree heavy flint glass prism
of best optical quality is included.

Price $75.00

#L4020b CAMERA ATTACHMENT# will fit in place of the observing telescope. It
is fitted with long focus objective and standard plate holder 2 1/2"x
2 1/2". The plate holder is provided with swivel for proper focusing of
the spectrum. The slit is so arranged that four exposures can be made on
one plate.

Price $20.00

#Cat. No. L4020c SCALE TUBE.# The third arm of the instrument can be easily
attached and rotated and clamped in any position. It may also be used for
holding a second Collimator.

Price $20.00

#Cat. No. L4021 STUDENT'S SPECTROMETER.# This instrument is in every
respect similar to our L4020, but some of the higher finish has been
omitted. All the essentials are carefully constructed and the optical parts
are of the best quality. The circle is protected but only one vernier
reading to 30 sec. is fitted to the instrument. The magnifying glass is
omitted.

Price, including prism $60.00

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TRANSCRIBERS' NOTES

General: Corrections to punctuation have not been individually noted.

General: Inconsistent spelling of catalog/catalogue preserved as in
original.

Page 7: magnifiing corrected to magnifying and celestrial corrected to
celestial.

Page 17: intensisy corrected to intensity.

Page 18: hundreths corrected to hundredths. LaPlat