On hygrology, hygrometry, and their connexion with the phenomena observed in the atmosphere / by J. De Luc.

  • Luc, J. A. de (Jean André), 1727-1817.
Date:
1812
Catalogue details

Licence: Public Domain Mark

Credit: On hygrology, hygrometry, and their connexion with the phenomena observed in the atmosphere / by J. De Luc. Source: Wellcome Collection.

Provider: This material has been provided by Royal College of Physicians, London. The original may be consulted at Royal College of Physicians, London.

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    ties of evaporated water that can subsist in one cubic foot of air with these three degrees of heat 3 but by the rate of its pro- gress, this correspondence may be continued to higher and lower temperatures, as I shall explain, after the following indi- cation of the immediate effects observed on the hygrometer of j each increase of 1 grain at the three temperatures. In the first two columns of the table, the points of the hygrometer \ cease to be indicated at the period when dew appeared on the side of the vessel. Table of mois- ture indicated by the hygro- meter at differ- ent tempera- tures. Grs. of water in 1 cubic foot. 1 2 3 4 5 6 7 Points of the Points of the Points of the bygr. at temp. hygr. at temp. hygr. at temp. 50°. 55°. 60°. 0 0 0 15*2 145 13 '9 29-9 28*5 27-6 51-6 47*2 43 2 74-9 64‘1 ' 55- 89-8 78-6 68’3 93*9 82*1 966 Remarks on 23. This table shows the progress of the effects on the hy- this table. grometer of the evaporation of the successive grains of water. These increases were stopped, as I have said above, by some water being deposited on the sides of the vessel. This effect took place for the 6th grain with the temperature 50°, and for the 7th grain at 55° : however, this happened only when the grains were entirely evaporated, during which time the hygrometer had moved 3 but there was no fixed point to be ob- tained correspondent to the new grain of water, since a part of it at last was deposited on the sides of the vessel. Account of the 24. The tables which follow this, in my work, serve to corn- die work *eS these results, by the rules of interpolation, for obtaining the intermediate terms not given by the experiments 3 and also to continue the same series, on one side, up to 98 of the /Aer- mometer, and on the other, for a particular purpose, down to 0. The table ix., which is the result of all these combinations, is constructed in such a manner, as to afford immediately the an- swer to the following questions, very important in meteorology. Questions av- - I. A point having been observed on the hygrometer in the open