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161)

whose particles likewise, being in continual motion successively attract, dissolve, and carry off, those on the surface of the fluid; while the [[strikethrough]] sam [[/strikethrough]] small quantity of air contained in the receiver, lying at rest over its surface, dissolves only an almost imperceptible part of it: the small quantity lost being, in this case, almost solely affected of heat. _ Further, it appears that ice, or water which has no more heat than is necessary to keep it fluid, evaporate sensibly in the open air; while they sustain no sensible loss, under the same degree of cold, [[underline]] in vacuo [[/underline]]; and that therefore heat can be considered only as accessory to evaporation, which it promotes by repelling the particles of fluids from the surface, and from each other, whereby they are attenuated, their surface is increased, and the air thereby enabled, as happens in other solutions, more speedily to dissolve and keep them suspended. So that tho' the action of ^ [[insertion]] the [[/insertion]] air on water and other fluids is not the [[underline]] sole [[/underline]], yet it is the [[underline]] principal [[/underline]] cause of evaporation: for though the particles of water are driven from its surface by the repelling power given them by heat, yet it is [[underline]] principally [[/underline]] by the attraction between water and air that they are raised from the surface, and by the same continued action remain suspended. _ Thus far Dr. Hamilton, according to the Monthly review, for May 1769. p. 394.
[[margin]] Objected to. [[/margin]]
I am inclined these experiments were not made with due circumspection, and that many material circumstances are not taken into the account, as no notice ^ [[insertion]] is taken [[/insertion]] of a proportional quantity of air containing also a proportional quantity of light & heat, but all is suppose to be air; certainly the free access of air to the open quantity of spirits of wine, brought with it also a free and continul current of heat along with it. _ His account of these experiments is contrary to the clearer experiment on p. 152. wherein appeared the most vapor with the less air, and less vapour or exhalation with more air. _ I cannot think his state of the case for evaporation will hold, anymore than his old adopted powers of repulsion & attraction.
[[margin]] On the transparency of a luminous object through a luminous medium, as Electric matter, [[underline]] Aurora Borealis [[/underline]]. &c [[/margin]] 
The said reviews p. 397. in their account of this author's opinion about the tails of comets, and speaking of the similarity between some of their effects and those in electricity, they say, "To the instances of this resemblance, the authors has given, he might have added the very similar effects [[strikethrough]] of [[/strikethrough]] which the electric matter and the [[underline]] Aurora Borealis [[/underline]] produce upon the magnetical needle: the

Transcription Notes:
Added ) to no. Added spaces between [[strikethrough]] text [[/strikethrough]] to enhance searchability of "text". Same again for [[underline]] Vacuo or Vacus? Where an insertion I transcribe [[insertion]] text [[/insertion]]. Also transcribe the ^ if there. Sometimes I put [[superscript]] r [[/superscript]] for Dr. but othertimes its not nec. Don't think you need to here but can if you want. The ^[[text]] is used by the Transciption Centre to indicate handwritten amendments to typed script. Where there is a margin note I normally transcribe as [[margin]] text [[/margin]] If there are margin notes on both sides of the text then [[left margin]] text [[/left margin]] etc. Anything yr not sure of transcribe as [[?]] - with best guess if poss. Any transcribers note is to go in this section.