[ Adapted from 960227 MMDigest ]

Over 100 years ago a punched paper "music roll" was used to control
a complex telescope built to photograph a total eclipse of the sun.
It is described on page 360 in the book, "Stars and Telescopes", by
David P. Todd, published in 1899 by Little, Brown & Co., Boston.

  "An arrangement of multiple cameras for observation of solar eclipses
was first worked out by the writer for the total eclipse of 22
December, 1889, at Cape Ledo in West Africa.  In all, 23 instruments,
chiefly photographic, were attached to a massive polar axis, and
pointed parallel to each other, following accurately on the eclipsed
Sun.

  "The engraving opposite illustrates many of them; also in the
foreground are the pneumatic contrivances by which exposing shutters,
plate-holders, and all other moving devices for eclipse observation
were operated automatically.

  "The control was effected by a perforated strip of paper, similar
to the music sheets now commonly used in automatic organs.  Each
perforation in the eclipse sheet represented, not a musical note, but
a mechanical movement of some particular device.

  "... The set-up worked perfectly but, unfortunately, on the day
of the eclipse the Sun was totally obscured by clouds."


The engraving apparently was produced by a non-astronomer: although the
rendering of the player pump-organ seems accurate (the artist probably
visited a local organ store), the astronomical devices seem contrived,
and the paper-roll "eclipse sheet" looks like it was the target of a
shotgun blast!  The caption says: "The Pneumatic Commutator and
Photographic Battery of Eclipse Instruments (Todd)"

Robbie Rhodes