3-008-773 - The Print Collector/Heritage Images

Instruments used by Mr. Glaisher during his balloon ascent, 1862. '1. Barometer; 2; Wet and Dry Bulb Hygrometer; 3. Daniell's Hygrometer; 4. Chronometer; 5. Bucket of Water to keep Bulb wet; A. B. Shields to protect Bulbs from radiation...Mr. Coxwell having planned an ascent with his large balloon from the Crystal Palace, I availed myself of the offer of a seat in the car for the purpose of taking a series of observations upon the variations of temperature and the several hygrometrical states of the atmosphere at moderate elevations...These instruments had been made by Messrs. Negretti and Zambra with great accuracy...The balloon left the earth at 4h. 40m. 10s., laden with thirteen gentlemen and a large amount of sand for ballast, and, under the influence of a moderate breeze, bore away slowly nearly south-east, passing successively Eltham, Hartford, to the village of Singlewell, near Gravesend...Between 4h. 46m. and 5h. the altitude and azimuth of the balloon were observed at the Royal Observatory, Greenwich...From a knowledge of the temperature of the dew point we know the amount of water then present in a certain mass of air'. From "Illustrated London News", 1862.