A treatise on the causes and principles of meteorological phenomena : Also two essays ; the one on marsh fevers; the other on the system of equality, proposed by Mr. Owen of New Lanark, for ameliorating the condition of mankind / by Graham Hutchison.

  • Hutchison, Graham.
Date:
1835
Catalogue details

Licence: Public Domain Mark

Credit: A treatise on the causes and principles of meteorological phenomena : Also two essays ; the one on marsh fevers; the other on the system of equality, proposed by Mr. Owen of New Lanark, for ameliorating the condition of mankind / by Graham Hutchison. Source: Wellcome Collection.

Provider: This material has been provided by The University of Glasgow Library. The original may be consulted at The University of Glasgow Library.

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    as it was by the supervention of clouds. A similar effect was produced by an awning of thin muslin, and in a less degree by the shade of trees, houses, or other elevated objects, which, to any extent, limited or re- duced the view of the sky, as seen from the place where the thermometer was laid. On windy nights, Dr Wells found that no reduc- tion in the atmospheric temperature close to the ground took place, beyond what was exhibited by a thermometer four feet above it. And in fact, other things equal, the sinking of the atmospheric tempera- ture close to the ground was greater, in proportion as the air subjected to observation was calmer, and from its local position, such as being on a low-lving plain, or in a slight hollow, less liable to be displaced by slowly progressing aerial currents. This effect of wind, and the similar one produced by slopes, such as the sides of hills present, in consequence of their al- lowing the cooled, and, therefore, the specifically heavier aerial particles nearest the ground to roll downwards, Dr Wells very properly ascribed to the circumstance of uncooled portions of air from above, being rapidly and successively brought into contact with the radiating surface; the temperature of which was prevented from sinking, in consequence of the caloric which those uncooled portions of air commu- nicated. These and similar observations Dr Wells success- fully applied to explain the phenomena of dew. In order to ascertain the amount of dew deposited, he usually employed swandown, which, being one of the best radiators of caloric, indicated, by means of the