1) The author investigated the effect of melting temperature on the graphitization of pig iron, and found the fact that graphite content in the melt varied with its oxygen content which depended on the partial pressure of oxygen of the atmosphere and the velocity of reaction between oxide and carbon in the melt. The author is of the opinion that the well-known theory demonstrated by Piwowarsky is improper. 2) The coke pig iron was melted in vacuum furnace at high temperature The structure and properties of the melt changed to the same as those of Swedish charcoal pig iron. 3) The structure which consisted of the fine eutectic graphite colonies surrounded by continuous net work, was obtained by melting the pig iron in vacuum. From the structure, it was sujested that, on cooling, the fine eutectic graphite colonies at first separated out and then the final liquid, comparatively more impure, solidified around them, forming the continuous net work structure. 4) Cementite scarcely crystallized out even by rapid cooling, when the molten pig iron, low in silicon, was cooled in vacuum state.

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The writer measured the shearing strength of carbon and alloy steels in their heattreated conditions having the tensile strength 40-220kg/mmmm²(25-140ton/ ″) and obtained the following results:
i) The shearing strength had a close relation to the tensile strength and was given by the formula (1)
S=10+0·58R……(1)
Where S=Ulthmate shearg strength in kg/mmmm²,
R=Ultimate tensile strength in kg/mmmm².
The above formula was applicable not only to various steels but also to cast iron and non-ferrous metals.
ii) The ratio of shearing strength to tensile strength varied from 0·60 to 0·85 according to compositions and heat-treatments of steels and was generally proportional to Charpy impact value.

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Nach die von Cantor entwickelte Methode des maximalen Blasendruckes wurde die Oberflächenspannung von flussigen Eisenlegierungen der Systeme Fe-C, Fe-P-C, Fe-Si-C, Fe-Mn-C und Fe-S-C gegen Wasserstoff ausgemessen. Es wurden schon einige Messungen an Eisen von Quincke, Drath und Krause vorher ausgeführt und die Ergebnisse veröffentlicht. Die Temperaturabhängigkeit ist aber damit nicht gut zu erfassen und der Einflusz von verschiedenen Elemente auf die Oberflächenspannung des Eisens wurde auch gar nicht bestimmt. Es sollte daher in meiner vorligender Arbeite hauptsächlich so erweitert werden, wie Kohlenstoff, Phosphor, Silizium, Mangan und Schwefel die Oberflächenspannung des Eisens becinflussen und noch die Temperäturabhangigkeit der Oberflächenspannung der Eisenlegierungen festzustellen.

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