Unpublished manuscript, 'On a perspective microscope' by George J [James] Burch In 1874 the author discovered a form of microscope giving constant magnification along the optic axis, so that objects were shown by it in microscopic perspective. By writing (f1+f2 + H) for the distance between two thin lenses, he obtained for the formula of the system f2(f2 + H)u - f1f2 (f1 + f2 + H)/Hu - f1 (f1 + H) = v; u being the distance from the object to the first lens, and v that from the second lens to the image. Annotations in pencil. Includes four pages of diagrams relating to Burch's microscope. Received 7 January 1887. Read 27 January 1887. Communicated by [John] Russell Reynolds. Written by Burch at 6 Broad Street, Oxford [England]. Whilst the Royal Society declined to publish this paper in full, an abstract of the paper was published in volume 42 of the Proceedings of the Royal Society as 'On a perspective microscope'. 1887