Since little is known quantitatively about the effect of limestone on the viscosity of cupola furnace slags, the writer experienced this important problem. The viscosity of molten slag was measured with a viscometer based on rotating cylinder method. As any refractory material is attacked by molten slag, he used a rotating cylinder covered with platinum and a platinum crucible, and the temperature of the slag was measured with a Pt-Pt. Rh thermocorple steeping in it directly,
He melted iron in cupola furnaces adding limestone 0-10% of the former, and found that slags which were made using limestone 1% in 0.1 ton cupola and 4% in l ton cupola have the smallest viscosity and the lowest melting temperature. Cast iron made in this manner also shows the better chemical and machanical properties.
This is probably due to the reason why slags which have smaller viscosity and lower melting temperature cover well over the upper surface of glowing cokes protecting cast iron from its bad influence, and the chemical reaction between molten slag and iron easily performed.

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In the main part, author treats the equilibrium of Fe-C-O₂-system at steel making temperatures by melting carbon and oxygen bearing iron in the gas stream of carbon mono-oxide and dioxide mixture. As the results of his experiment, it was proved that the oxygen content of the molten steel in equilibrium with the gas phase, is proportional to the ratio pco₂/pco, and carbon content to p²co/pco₂. On these accounts, he proposed that the two equilibriums, FeO_(Fe)+CO=Fe+CO₂ and C_(Fe)+CO₂=2CO, should be considered simultaneously as the carbon-oxygen equilibrium in steel making process instead of FeO_(Fe)+C_(Fe)=Fe+CO as was usually accepted. Further he constructed also the equilibrium diagram of Fe-C-O₂-system qualitatively in the region of molten steel.
As an appendix of his main paper, he described the hydrogen reduction method of oxygen determination in iron and steel. Some remarkable points of his method of determination are in the treatment of reduction products, H₂O, CO₂ and CO. Here H₂O was absorbed by P2O5 and CO₂ by soda lime as usually, CO is oxidized by I₂O₅ to CO₂ selectively and after retaining free iodine with metallic copper chips, secondary formed CO₂ absorbed by soda lime and weighed.

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In electrolysis of iron, the cathode suspended by springs, which have moderate elasticity and amplitude, is used. When electrolysis is carried on the cathode is blowed periodically by a hammer and oscillated.
The mechanism of the system: -
(a) Regulating the weight or the height of the hammer, the force of its blow on the cathode and consequent the maximum velocity of the oscillating cathode can be altered.
(b) The amplitude of the oscillation can be altered by altering the spring elasticity.
(c) The period of blows can be altered by altering the speed of revolution of the cam with which the hammer is handled.
The effects of oscillating cathode: -
(1) The suspentions in the electrolyte are swept off from the cathode surface.
(2) The diminuation of Fe ions on the cathode layer is prevented.
(3) The hydrogen babbles on the cathode surface are swept off.
(4) The accumlation of Fe-salt on the anode layer is prevented.
(5) The slime is swept off from the anode surface.
(6) The temperature and the concentration of the electrolyte are equalized.

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Various observers does not agree exactly as to the effect of phosphorus on the physical properties of steel; owing to the fact that its effect changes by the amount of carbon, manganese and other impurities in steel. The present investigation was carried out for finding the effect of phosphorus upon the mechanical properties of our basic open-hearth steel as rolled by means of eliminating the effect of carbon and manganese on the physical properties of steel. The results of it may be summalized as follows.
(1) On the plain carbon steel which contains carbon, manganese and phosphorus in simultaneously, the effect of phosphorus, under the same amount of carbon, was detected by means of eliminating the effect of manganese present.
(2) The effect of phosphorus on the tensile strength, yielding point and elongation of steel increases with the increase of the carbon content and the impact resilience, under the same amount of carbon and of manganese, decreases with the increase of the phosphorus content.
(3) So far as the relations between chemical compositions and physical properties of steel are concerned, the presence of about 0·08 phosphorus for plain carbon steel does not to be damaged in practice the mechanical properties of steel.
(4) The relations between chemical compositions and mechanical properties of our basic openhearth steel as rolled may be expressed by the following empirical formula
T=0·33C+0·008CP+0·64P+0·006CMn+0·02Mn+30·2
Y=0·15C+0·00087CP+0·37P+0·0009CMn+0·11Mn+18·0
E=312/C-(0·0022CMn+0·011CP+0·127P)+22·0
where; T=Tensile strength in kg/mm² Y=Yielding point in kg/mm² E=Elongation in % G.L. 50mm dia of spicimen 14mm C=Carbon content in %×100 Mn=Manganese content in %×100 P=Phosphorus content in %×100

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