Correspondence and related papers concerning magnetic instruments and photographic registration. The correspondents include H.E. Roscoe, B. Steward, G. Forbes, H. James, W. De La Rue, B.A. Gould, L.M. Rutherford and C. Brooke. The papers include vertical and horizontal section plans of the Horizontal Force and Declination Photographic Apparatus; a paper by J.D. Forbes titled 'An account of two artificial hemispheres representing graphically the distribution of temperature and magnetism from the Earth's equator to the North Pole'; two circulars advertising Singer's compass; various prints of photographs used as specimens to illustrate certain processes of photography; a price list for photographic paper and chemicals; a paper on astronomical photography by L.M. Rutherford; galley-proofs and a photograph concerning T. Skaites' Pistolgraph; and a pamphlet advertising photographic portraits produced by E. Edwards.