Correspondence and papers concerning magnetic experiments, including experiments on the induced sub-permanent magnetism of hot rolled and cold rolled malleable iron; proposals to test manufactured iron by magnetism and the findings printed by S.M. Saxby in 'Engineering'; a paper by J.E.H. Gordon and W. Newall on the 'effects of small variations of temperature on steel magnets'; the attraction of magnets by J. Carpenter, with statistics, a summary and relevant mathematical formulae; computations on assumed laws for induction coils and linear magnets; and the Borgar Tubular Bridge magnetic experiments, with correspondence on preparations, outlines of the experiments to be undertaken, observations and remarks on the findings, and a journal of proceedings by J. Carpenter. The correspondents include W. Fairbairn, W.G. Romaine, G.G. Stokes, J.C. Clark, F.J.O. Evans and H.C.G.G. Lennox.