Italy, c. 1500
The Victoria & Albert Museum
Sandglasses of the Sixteenth Century were constructed from two similarly-sized glass ampoules which were sealed (often with wax) and bound with fabric at the joint. “Sandglass
is something of a misnomer as the “sand” wasn’t sand at all, but rather a material which would be less sensitive to moisture. Powdered metal, rock or eggshells were most commonly used. The different materials used provided different hues for the sand.
These four sandglasses from Italy are mounted in a single frame and run for different periods--probably subdivisions of an hour.
Made in 1500, there’s some understandable wear to them. Since they’ve been in the V&A, many have tried to time them precisely. However, an exact timing has not been possible since, after five hundred years, the particles no longer run freely.