Altizamuth Circa 1860s

This rare, early Pocket Altazimuth combines a sighting telescope with a magnetic compass for determining bearings, and a pendulum (or wheel) clinometer for determining vertical inclinations.

There are viewing aspects to the left and right hand side, one for the compass, the other for the clinometer. 

Both viewing aspects are sealed and protected by clear, undamaged glass. Both instruments are activated by top mounted release screws. The clinometer is viewed by an eyepiece to focus the scale.  The compass is activated by a top screw, and is graduated to the points N,S,E W.

It was said to be especially useful for travellers and military surveys, as it was small, compact and accurate.

Although no maker’s name is visible, this particular design was usually manufactured by C. F. Casella, the renowned manufacturer of Scientific Instruments in London, from 1810.
The following description is taken from the original 1862 Casella Catalogue;
"Casella’s pocket altazimuth, for travellers and military surveyors, altitudes, azimuths, compass bearings, clinometric degrees and levels are all obtainable by this handy and accurate little instrument."

This instrument is made of brass and measures 6 inches (7 inches with telescopes extended), and the compass diameter is 2.5 inches. On both sides the glasses are clear and free from chips or scratches. The telescope lenses are also in perfect condition.

The original design of the Pocket Altazimuth has been attributed to Francis Galton, (1822-1911), an enormously talented gentleman scientist who was a Fellow of the Royal Society of London, and whose work ranged over a number of fields.

The Altazimuth is in very good overall condition and is presented in a fitted, felt-lined, wooden box.