The method recommended by the Sectional Committee consists of the following processes:
(1) Revealing the grain structure of steel.
Carburizing at 925°C for 6 hrs. (in accordance with McQuaid-Ehn's method) is adopted as standard. If necessary, "gradient quench method" (in accordance with Vilella-Bain method) and "double-quench method" (in accordance with Tomikawa's method) may be also employed.
(2) Determinstion of the gtain aize.
Grain structure thus revealed ahould be examined microscopically at the magnification of 100 in diameter and a grain-size-index-number derermined which corresponds to the strictly prepared Grain Size Chart The Grain Size Chart consists of the 8 photomicrographs of hyper-eutectoid structure of steel, cach denoting the index-numbers 1 to 8 progressively. The index-numbers are arranged to conform to the geometrical ratios, in which for instance No.1 signifies the existence of 16 grains per mmmm2 actually, No.2 32 grains/mmmm2, No.3 64 grains/mmmm2 and so on.
The present method is the outcome of about one and half year's carnest efforts in which a number of specialiste have coopeted. The author certainly believes in that the present method will be useful for the study of steel-making and further treatments of steel so far as the steel quality concerns.

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To find. the susbstitute for the most valuable nickel-chromium structural steels, investigations were made in the following three lines:
(1) Statistical studies were performed on the physical and other propeties of several steels now in current use. As the substitute for low-nickel-chromium steel (C 0·3-0·4, Ni 1·0-1·5, Cr 0·5%), all of chromium steel (C 0·4-0·5, Cr 1·5-2·0%), 75-kg chromium-molybdenum steel (C 0·25-0·35; Cr 0·8-1·2; Mo<0·3%) and 80-kg chromium-molybdenum streels (C 0·4-0·5, Cr 1·5-2·0, Mo<0·5%) were found to be suitable, especially the second being best.
(2) New kinds of alloy steel were found. which contain less nickel and increased chromium and manganese as follows:
C% Mn% Ni% Cr% Mo
0·1-0·15 1·0-1·5 1·5-2·5 2·5-3·5 <0·5% (Suitable for carburized parts)
0·28-0·35 0·8-1·5 1·5-2·0 2·5-3·5 <0·65
Properties of both of these steels were almost equal to nickel-chromium steels with 4-5% Ni, which had been thought the highest in quality among steels used now.
(3) Other new kinds of alloy steels were found, which contain silicon, manganese and chromium, but no nickel, as follows:
C% Si% Mn% Cr%
<0·15 1·0 1·0 1·0 (Suitable for carburized parts)
0·25-0·35 1·0 1·0 1·0 (2·0, 3·0)
0·50-0·60 1·0 1·0 1·0 (2·0, 3·0)
All of these steels proved to have sufficient strength, but being a little short of impact value on accout of their tendency to grain-growth and of rather much non-metallic inclusions. Nevertheless, when properly handled, they could be used for automative and other machine parts as the substitute for 3-5% nickel-chromium steels.

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The common method of manufacturing electrical sheets was deait with in the Journal, Iron and Steel Institute, Japan, Vol. XX, No.1. Since then, the electrical sheet has been studied well in Europe and the United States, and they have produced some sheets which were excellent in their electric and magnetic properties. Nowadays when transformers of higher capacity are being in demand, we naturally expect more and more superior electrical sheets with the higher flux density and the less iron loss. The present paper deals with the development and manufacturing methods of the transformer sheet in Europe and the United States as well as the actual practice in Japan together with part of the experiments conduced by the author. Then, the possible and commercial method of manufacturing excellent electrical sheets with least iron loss were also referred to.

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The present report is a part of the research on the apparatus which has been used for the determination of hydrogen in steel and iron by the vacuum beating method (K. Tawara, Journal, Iron and Steel Institute, Japan, XXV, 413, 1939). In the present report, the apparatus for microanalysis of the gas sample was described. It was especially designed for analyzing 0.01ml hydrogen and consists of the 10.1ml burette graduated in 0.05ml, three absorption pipettes, an explosion pipette and an oxygen generator. The upper part of the burette is a capillary of 1.5-2mm bore and had a capacity of 0.1ml, graduated in 0.01 or 0·02ml.

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