Three Pulse glasses
About this digital image
3 Pulse glasses. First; Half-minute sand glass, fixed in wood stand, split. Times at 30sec. Second; Pulse glass in chromium plated case, with removable lid and split ring for suspension. Case marked "1/4 min", timed at 16 sec. Third; half minute sand glass, in brass case designed for suspension, screw-top missing. Times at 31 1/2 sec
You can use this work for any purpose, including commercial uses, without restriction under copyright law. You should also provide attribution to the original work, source and licence.
Creative Commons Attribution (CC BY 4.0) terms and conditions https://creativecommons.org/licenses/by/4.0