Description
A 1950’s Caella London Whirling psychrometer, also known as a sling psychrometer, for measuring humidity, designed by J. J. Griffin & Son Ltd. and made to B.S.2842 by Casella, London, UK, 1950-1953. Contains wet and dry bulb thermometers.
Whirling or sling psychrometers are types of hygrometers for measuring air humidity. They contain two thermometers, one of which has a bulb kept wet with a cloth soaked in distilled water. The device is whirled rapidly in the air, and the difference in the readings between the two thermometers gives a measure of humidity.
Measurements: 22,5 x 17 cm.
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Van Leest Antiques
Van Leest Antiques
Van Leest Antiques, based in Utrecht in the Netherlands, specialises in antique scientific and medical instruments. Their collection covers mainly scientific and medical antique instruments: barometers, globes and planataria, nautical instruments, anatomical models, and pharmacy items. Toon Van Leest travels regularly in Europe and visits trade fairs, auctions, and antique dealers to collect stock and to find pieces to fulfil his clients' unusual requests.
As well as being an avid antique collector and dealer, Toon Van Leest is also a dentist. He believes that antiques are a stable investment, not reliant on trends or fashion, and have truly lasting value. Above all, he says, antiques are timeless and never lose their beauty.