The B&C Spectrograph is a somewhat evolved version of the classic
reflection-optics spectrograph built by Boller & Chivens in the late
1960's. It is capable of moderate-resolution (
1--5Å) with
good throughput from the atmospheric limit at 
3200Å to the near-IR.
A provision was implemented in the mid-1970's
for multi-order ``echellette'' spectroscopy with a
cross-dispersion prism, providing 1--2Å resolution and complete coverage
over 
3200 -- 8000 for a detector of sufficient size.
Light enters the spectrograph just behind the Cassegrain mounting plate
through an aperture assembly which currently accepts one of two
reflective slit plates (
3). The field around the slit is reflected to
a CCD/intensified TV camera for acquisition and guiding (
5).
Light which passes the slit encounters in order: an electronic shutter for
controlling exposure, an order-separating/neutral density filter wheel (
7),
a below-the-slit viewer for alignment/focusing purposes (
5),
and then the f/9 off-axis paraboloidal collimator(
6). The primary
disperser is a standard 102
reflection grating (
2) chosen from a wide assortment of available options.
Following the grating, the light can be cross-dispersed with a 60
quartz prism (
2.3)
or sent directly through a manual camera shutter to the spectrograph
camera. The camera (
10) is an on-axis, semi-solid Schmidt with the
corrector element air-spaced from the sphere/secondary/field-flattener.
Slit demagnification
in the spatial direction is 5.44, for a resulting image scale of
54
/mm on the detector (1
= 18
m).
A CCD dewar (
12 and a separate manual) with integral window follows
the spectrograph. Calibration lamp illumination is provided via
a small mirror inserted above the slit(
4).
Appendix A presents four color photographs illustrating the external components of the B&C Spectrograph. A new user should become familiar with these photos! The sides of the spectrograph will be referred to in this manual as being those corresponding to the photos. ``Side 1'' thus refers to the side closest to the control room, with Sides 2 -- 4 corresponding to those seen when walking clockwise around the instrument. For the directionally-oriented, Side 1 refers to the west side, and Side 2 the south side, etc. The letters in square brackets appearing throughout the text refer to the same identifications marked in Appendix A.