With respect to the mathematical part of optics, the curvature of the images, formed by lenses and mirrors, has been correctly investigated, and the … - Thomas Young

I have... attempted to throw some new light on the general properties of matter in other forms: and on the doctrine of heat, which is materially concerned in them; and to deduce some useful conclusions from a comparison of various experiments on the elasticity of , on evaporation, and on the indications of s.

It is surprising that so great a mathematician as Dr. Smith could have entertained for a moment, an idea that the vibrations constituting different sounds should be able to cross each other in all directions, without affecting the same individual particles of air by their joint forces: undoubtedly they cross, without disturbing each other's progress; but this can be no otherwise effected than by each particle's partaking of both motions. If this assertion stood in need of any proof, it might be amply furnished by the phenomena of beats, and of the grave harmonics observed...

have enumerated, in a compendious and systematical form, the principal facts which have been discovered with respect to galvanic electricity; and I have fortunately been able to profit by Mr. Davy's most important experiments, which have lately been communicated to the , and which have already given to this branch of science a much greater perfection, and a far greater extent, than it before possessed.