William Bower Taylor

“ And after some little thinking, it occurred to me that if this medium be of the same nature as our atmosphere and other gaseous bodies, that is, if it be capable of being expanded by heat and contracted by cold, then the sun being a very hot body, and the heat being so much the greater the nearer we are to him, the density of the medium ought therefore to decrease with a decreasing and increase with an increasing distance, the same as Newton would have it. ”

“ We may hence fairly conclude that there might be a fluid medium pervading the heavens, and all bodies, of such activity that no sensible difference could be observed in the intensity of its action on bodies in a state of quiescence, or moving with a velocity not only six million, but several million million times greater than that of light ! ”

“ If gravitation depends upon the action of an elastic medium such as Newton supposed, which grows rarer aud rarer as you approach the dense bodies of the sun and planets, there ought to be some reason for this variation of density ”

“ Unfortunately "two properties" are wholly insufficient either to set or to keep a system of molecules in motion. Matter thus constituted, (with only " two properties,") with any amount of motion superimposed, could never make a cosmos. ”

“ By extending the principles to find the temperatures of the planets, we arrive at an interesting conclusion, namely : supposing them to be all of the density of our earth, we bring out very nearly the amount of gravitation toward each of them which is actually found to exist. ”

“ Though regarded mathematically, such an inference would be strictly true, yet since the difference between the forces ' will depend on the activity of the medium, and since this activity will be increased in proportion to the tenuity of the parts of the medium, it is evident that the aetherial atoms may be so small, and the activity of the medium consequently so great, that the swiftest motions we know of could produce no sensible difference in the vigor of its action. ”

“ Therefore if as Newton imagines, the particles of the planets be impelled toward the sun by the inequality of the pressure on their further and nearer sides, the denser parts of the medium pressing more forcibly than the rarer, the same reason will likewise hold good why bodies should be impelled toward the planets an ”