The most suitable temperature for the breaking-down of the cast structure of a series of bronzes containing up to 30 per cent. tin, was determined by forging small cylinders and observing the amount of cracking obtained. Both pure tin-copper alloys, and a similar series with increasing amounts of phosphorus, were examined. Small slabs of each alloy were rolled in the most suitable temperature range, as indicated by the forging tests, and ultimately the whole series of alloys with tin up to 25 per cent. was obtained in the form of thin strip, with the exception of a range form about 17-19 per cent. tin which could not be successfully fabricated. Micro-examination was first made of straight tin-copper alloys in the form of thin strip quenched from temperatures corresponding to the phase areas in the accepted tin-copper equilibrium diagram; the effect of phosphorus additions on the phase changes was then explored. An examination of alloys quenched from 500° C. gave sufficient data on which to base ternary diagram at this temperature. Curve are given showing the work-hardening of a series of alloys by cold-rolling, and tensile properties are given for a number of alloys, in the soft and the hard rolled conditions.