On heating steels containing four different carbon contents at 800°, 900° or 1000° with different packing materials, the conditions of carburization or decarburization of steels were studied. When the carbon content in steels exceeds about 0.5 percent, the decarburization takes place at 800° on heating with carbon powder, though it is prevented by mixing carbonate. If the air penetrates through the packing material during heating, the decarburization is conspicuous. The carburization is markedly energized by adding sodium carbonate, besides barium crabonate. When the carbon content in steel is more than that corresponding to the Acm point, the rate of carburization is very sluggish, even in the case in which a powerful carburizing agent is used. The presence of a small amount of moisture in the carbon powder tends to promote the carburization, while the size of the carbon powder seems to be practically no effect provided it is fine within a certain limit.

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This essay consists of 6 chapters and explained the mechanism of the oxidation of the pig iron in converting it to steel.
During the steel refining process, we must at first oxidize and eliminate the impurities from the molten metal.
Explaining the mechanism and the place where the reactions would take place in the process certified the theory with the aid of the microscopic examinations.
Later, writer has proposed the theoretical difference of the electric furnace and open hearth furnace as to the reactions, and concluded the metal bath of the electric furnace is allowed to deeper dimension than that of openhearth furnace for the same mass or weight of the molten pig iron.

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Metals of the alkali and alkaline earth groups react with dilute acids according to the following equation
Below 10^-3 normal, this reaction does not proceed and the reaction of the second kind alone takes place as follows:
This means that metal atom reacts directly with water molecule (Molecular reaction). In the case of magnesium, this molecular reaction was not decisively proved, but it seems very probable that equation (2) does also exist, because magnesium behaves, in many properties, quite similarly to alkaline earth elements. These were the conclusions of the previous paper.
Thus, the view that chemical reaction between magnesium and aqueous salt solutions is due to the interaction between Mg atom, H₂O molecule and Cl^- ion was proved not unreasonable, yet, it was not quite clear whether H⁺ ion does participate in the reaction mechanism or not. The present paper deals with this important question. The reaction mechanism itself is moreover discussed in some details. The experiments were carried out on solutions with various [H⁺], keeping [Cl^-] always constant and equal to IO^-2 normal. The reaction velocity diminishes with diminution of [H⁺], but does not vanish when [H⁺] becomes zero, leaving very large velocity. The velocity remains constant between [H⁺]=10^-4 and 10^-11, being perfectly independent of H⁺ ion Therefore, we can conclude that some reaction other than (I) is taking place, While the (I) reaction accelerates considerably when the solution is stirred, as may be expected, the reaction below [H⁺]=10^-4 retards very nuch. This fact also confirms the existence of some reaction different from (1). Taking these experimental facts into consideration we must conclude the existence of the fundamental reaction (2). for magnisium Stirring effect was explained by assuming the auto-catalitic action of some intermediate compound. The minimum point in the velocity-log [H⁺] curve can also be explained by this theory.
In conclusion, the author put forward the theory that Mg atom, H₂O molecule and Cl^- ion react each other forming some unknown intermediate compound, which decomposes on accumulating, giving off H₂ gas and regenerating Cl^- ion. The reaction accelerates when the compound accumulates around the specimen but retards when it is scattered away by stirring. H⁺ ion does not take part in the reaction mechanism.

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