Miscellaneous correspondence and works on scientific matters, including papers of the Chemical Association of the British Association; reports on the northern telegraph from the 'South Australian Register'; a government report on Post Office telegraphs; a piece by G. Forbes from 'Nature' on the observatory at Mount Vesuvius; a piece by E.C. Garbett from 'Nature' on volcanoes in Southern France; plans for a water telescope; 'the angles of incidence and reflection' by P.J. Brine; various trials of navy telescopes; experiments on light waves and optics; M. Croullebois's account of the double refraction of quartz; G.G. Stokes' views on the optical action of magnets; and various ways of squaring the circle, with a paper by W. Hayden. The correspondents include W. De La Rue, J.C. Clark, G.G. Stokes, J.D. Everett, J. Challis, C. Wheatstone, H.E. Roscoe, W. Huggins, W. Spottiswoode, A.R. Clarke, A.H.C. Fizeau, E.J. Routh, C. Brooke and J. Marshall.