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
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.
4/16 page 4
![in the last numbers of your Journal, were destined to show, from our own experiments and atmospherical observations, what are the nature of the electric fluid, and its interference in me- teorological phenomena ; and I now come again to the same subject, under another point of view.' ltain not from 1. My observations of the aerial electroscope, published in moisture m the y0ur ]\j0 124} show, that the changes in the phenomena exhi- bited by this instrument have no connexion with the state of moisture in the ambient air. I proved also, in the same paper, this important point in meteorology, that rain does not proceed from a moisture actually existing in the atmosphere. This, if it be certain, overturns the new theory of chemistry ; for thus butthepon- ,rai» cannot proceed from any other cause than that of a decom- derable part of position of the atmospheric air itself, a fluid sui generis, the ponderable part of which must be water. Grounds of the 2. But this conclusion rested on the indications of the hygro- conclusion. meter, Mr. De Saussure’s observations, and my own, on high mountains 5 in the very region of the atmosphere we saw the clouds forming around us, and pouring rain, while an instant before our hygrometers testified, that there was very little Canthehygro- moisture in the air. But here a question arises : is the hygro- meter be de- „ pended on ? meter an instrument to be depended upon, for the purpose of indicating the real quantity of moisture, or evaporated water, mixed with the air, in the place where it is observed ? This an lrnpor- 3 This, Sir, is a very important question, as well in natural, as in experimental philosophy j and I wish, through your valua- able Journal, to attract the attention of your readers to this instrument. I had very little hope of success on this point, when I wrote my preceding papers in your Journal; because, from a circumstance which I shall explain hereafter, none of my hygrometers could be found ; but it is not the case now. Progress made 4. I had already made some progress in the correspondent iu the inquiry. researches of the indications of the hygrometer, and the phe- nomena of rain and fair weather, when, in 1786, I published in London my work, Idees sur la Meteorologies 5 but I had carried them much farther, when I delivered to the Royal Society my papers on hygrology and hygrometry, published * This work may be had of Messrs. Dulau and Co, booksellers in Soho Square. im](https://iiif.wellcomecollection.org/image/b2851984x_0006.jp2/full/800%2C/0/default.jpg)
