Experiments for pig-making with a cement-calcining rotary kiln by Basset process were previously carried out in the Yawata works of Nippon Seitetu Kabusiki Kaisya. Following these, the Titibu Cement Kaisya, Osaka Yogyo Cement Kaisya and Asano Cement Kaisya (Kawasaki Works) have made the pig-making experiments using similarly rotary kilns, and reached the present status.
In this paper, the results of experiments in these firms, the future trend of pig-making with a rotary kiln, etc. are outlined.

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In the present paper, the author proposes some useful methods for detecting oxygen in molten steels. The methods are based on the following computations.
1) The change of oxygen in molten steel of acid open-hearth melt may be known by the change of CaO% in the slag.
2) The change of oxygen in molten steel may be calculated by the change of deoxidizing elements, such as C, Si and Mn.
3) Accurate computabion for the boundary conditions such as oxygen before deoxidation, oxidation by flame and bed, amount of oxygen in solidified steels, etc.

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In investigating the cementation of pure iron and the decarburisation of carburised high carbon steels, a dilatometer, which is capable of varying freely the inner atmosphere, was employed. Thin tubular specimens 8mm in outer diameter, 0·75mm in wall thickness and 100mm in length taken as standard, were heated at certain constant temperatures for a long duration in a tubular heat resisting carburising box, in which solid carburising materials were placed or gas current applied. Since austenite increases remarkablely in volume as the cementation proceeds, an l contracts by the decarburisation, the stages of various changes accompanied with these phenomena were precisely traced under various conditions in the carburising box, by measuring the dilatation of the specimens.
The contents of the present paper are as follow:-
I Intro luction.
II Apparatus of experiment.
III Samples and experimental methods.
IV Preliminary experiments.
V Cementation of pure iron by solid carburising materials.
A Promoting action of BaCO₃ upon cementation.
1 Effect of ratio of BaCO₃ to charcoal
2 Heating time and cementation degree.
3 Cementation by repeated heating and cooling.
4 Cementation by various carbons.
5 Grain size of carburising materials and cementation power.
6 Cementation in vacuum and effect of air upon cementation.
7 Temperature and cementation effect.
B Promoting action of other carbonates upon cementation.
a Action of SrCO₃.
b Action of Na₂CO₃.
c Action of CaCO₃ and MgCO₃.
C Moisture in the carburising materials and cementation power.
VI Saturated cementation of iron.
1 Implication of saturated cementation.
2 Quenching tests.
VII Decarburisation of carburised high carbon steels.
1 Decarburisation in solid carburising materials.
2 Decarburisation in gas current.
3 Cementation of the soft steel and decarburisation of the carburised steel.
VIII Summary.
IX References.

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The requirement for raising the yield strength or proportional limit of 18/8 stainless steel is accomplished in a considerable extent by the age-hardening of previously cold-rolled sheet.
The development of this property, however, is expected to be achieved most effectively by the addition of some suitable elements to the plain 18/8 alloy.
The writers made some experiments on the influence of Ti, employing 5 test samples with a Ti content varying from 0 to 1·6% upon the mechanical properties in connection with the degree of cold-rolling and the temperature of aging which they recieve.
From the results obtained, it was found that a marked increase of the yield strength can be obtained by the appropriate aging of cold-rolled sheet, to which Ti has been added in a suitable amount.

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