18th Century Moroccan Etched Brass Astrolabe

Description

This antique Moroccan astrolabe was once used to cross the Sahara desert. It is made of brass, carefully and ornately etched with markings to indicate time, direction, star positions, and more. This amazing tool is considered the precursor to the modern smartphone: it gives you the time, your location, your horoscope, and even help you make decisions—all with the swipe of a hand.
This astrolabe makes an impressive wall decoration and conversation piece. Astrolabes became popular during the height of the Roman Empire and remained popular until about the 18th century, when they fell out of favor.
These multi-use tools consist of a circular stack of sliding features all embedded within a disk called a “mater”. A round plate containing a two-dimensional projection of the Earth’s latitudinal lines sits within the mater and, over that plate, another circular feature called the “rete” contains the locations of certain well-known stars in the sky. Over that, a straight rule pivots around to line up with time measurements along the edge of the mater. And on the back of the whole thing, a pivotable siting device helps find the altitude of a star—often the starting point of a calculation. (source: Smithsonian Magazine)
Often found in shipwrecks, this unusual scientific tool was located in the southern Moroccan desert town of Zagora. They are quite difficult to find in good condition and are treasured by collectors.
Details & Dimensions
18cm tall x 12cm wide (7in x 5in)
This item ships free worldwide directly from Morocco.
Handmade; please allow for minor imperfections and design variations. Please inquire with any questions or for more pictures.
This is an antique potentiometer, Model 3184D, built by Tinsley & Co in Essex, UK. The company still exists and still produces precision instrumentation to this day. This device was originally used to measure and characterize test cells, such as emf (voltage) and internal resistance. Inside the unit is an area for two 3V batteries and a Standard Cell to provide a known emf, by which the measurements on the unknown test cells are made. The actual measurements are made with a deflection meter, the components of which appear completely intact.
The unit is in good shape, as shown in the pictures. These types of devices can be used to measure very small potential differences, down to the microvolts even. A functional schematic is shown, and it appears a previous owner added a toggle switch to one of the power lines, possibly to save battery life when not in use. If you're in need of some spare parts, I'm willing to bet this thing is stocked with precision resistors.
Solid wood case, very sturdy construction, weighs about 22 lbs. The outside has some wear and tear as you would expect from a used piece of equipment, but it's overall quite nice. The top cover is easily removed from its hinges so it would make a great decoration on a bookshelf or in a cabinet.
They really don't make 'em like this any more!