Stresses induced in the metal on account of it being cast are here conveniently called casting-stresses, and in this paper their study is made from the standpoint of practice more in the quantitative manner than in the qualitative. As regards the underlying theories, papers which will appear in the future are expected to deal with them. Here at first, two actual pulleys of the same size, but with dimensions of different proportions were taken and investigated on the inducement of casting-stresses by a special procedure. Thus, in some concrete numbers, values of different inducements of casting-stresses due to various proportioning of each dimension were found. From this preliminary study on actual pulleys, a more detailed investigations were made upon various items, such as (a) the determination of the most suitable form of the specimen for the present study, i. e, the form which is the easiest to make, to machine and to handle and one which develops the stress inducement in such an exaggeration that errors accompanying their measurement may not introduce any serious effects in the results ; (b) inflrence of casting temperatures on casting-stresses ; (c) casting-stresses induced in the green and dry sand mould castings ; (d) position of the pouring gate and its effects on casting-stresses ; (e) casting-stresses when chills are used at some parts of casting ; (f) casting-stresses due to lapse of time ; and further of the most practical importance, (g) diminution of casting-stresses due to heat-treatment were dealt with, and the fact was found that by the means of definite temperatures and duration of heats, it is possible to completely release the casting stresses. In addition to the heat-treatment, (h) alteration of physical properties due to annealing were studied. A Resume and a Bibliography are attached.

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