1. Introduction.
A brief statement of the steel making process and development to the present days of the steel industry in Japan.
2. Past-war development of the steel plant.
The reconstructions and improvements of the steel plants, newly designed open-hearth furnaces built recently in the Kamaishi Mining and Co., Kawasaki Ship-building & Co. and the Kobe Steel Works, and the greater tonnages of production resulted from them.
3. Relations between pig-iron capacity and steel capacity, increased use of scrap.
Pig-iron production of the blast furnace plants in Japan, and compared with the amount required for steel production, increasing use of scrap.
4. Efficiency of steel plant and the steel making process.
Steel ingot productions of the steel plants in Japan. The improvements of steel making practice: - fore-freshing mixer practice and open-hearth furnace practice combined with fore-freshing mixer.
Talbot process using fore-freshed iron: - fore-freshing practice and Talbot furnace working practice using fore-freshed iron. Close the acid Bessemer plant.
5. Steel making process and fuel economy.
Utilizations of coke oven gas, blast furnace gas, and coal tar. Recovery of the waste heat from open-hearth furnaces, and the application to be extended to every sorts of furnaces. Steam generation by the waste heat of gas. Open-hearth furnaces slag used in the blast furnace charge and mill scale in open-hearth furnace.
6. Tables: Table of pig-iron production. Table of steel production. Table of pig-iron import, export and demand. Table of steel import, export and demand. Table of ferro-alloys consumption.
7. Supply and training of labourers.
Labourer in the open-hearth furnace working and regulation: One and three shifts per day and the working time. Numbers of labourers and monthly income in the Imperial Government Steel Works.
8. Present positions and future extention of the Japanese steel industry. Present position of the Japanese steel industry: Present steel plants and future extention scheme designing now. Japanese steel productions compared with those of other countries in Europe and America.
Table of numbers and capacities of the blast furnaces and all the steel making furnaces in Japan.

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Coal is a non-conductor of electricity, but when carbonized to coke it becomes a conductor. In order to study the progress of the carbonization of coal, the authors attempted to measure the electrical resistance of coal briquette during the carbonization.
Five kinds of coal were selected as the samples of this study, four of them being representative Japanese coking coals, the other a Chinese one.
The briquettes for this examination were prepared at a pressure of 600 kilos per sq. cm., the size being 1cm. in diameter and about 3cm in length.
In order to measure the electrical resistance Kirchhoff's bridge arranged with cell and mirror galvanometer was employed.
When the samples were heated, the galvanometer began to move at about 500° in the cases of all samples, and this temperature indicates the transition from coal to coke. As the temperature rose above 500°, the electrical resistance was recorded every one or five minutes.
Results thus obtained described almost a hyperbolic curve that we may express in the following equation.
xy=a
Where x shows the time at which the carbonization is juat finiahed.
y is the most probable final resistance at x.
a is a constant (the greater "a" becomes the more rapidly the carbonization occurs and vice versa).
Applying this equation we calculated the relation between temperature and time.
A large nichrome resistance electric furnrce in which about ten kilos of coke could be obtained was prepared for the carbonization at a temperature.
The same sort of coal was carbonized at a certain temperature both in this furnace and in Solvay's coke oven, and the properties, especially the crushing strength, of the two kinds of coke as above obtained were compared. In the case of coke derived from Chinese coal, even at 750° it could stand comparison with Solvay's coke.
We conclude that, in order to discover the best conditions from the point of view of fuel economy and other purposes, the following steps should be taken: - first, ascertain the relation between temperature and time requisite for carbonization; second, examine the quality of the coke obtained by the carbonization at such a temperature und within such a time.

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In the malleable iron foundry, it is generally believed that packing material is very important in annealing white cast iron to get a good malleable iron casting, but as the theory of annealing white iron has shown, the packing material is not necessary to make black heart malleable cast iron, although it is very important in obtaining white heart malleable which is manufactured by decarburizing castings. The author made a special installation and measured the decarburizing amount by the evolved gas during heating white iron castings at a high temperature; by this experiment it was possible for him to explain the mechanism of decarburization.
In addition, the author meassured the following effects:-
(1) The effect of the temperature on decarburization of castings when packing material is not used;
(2) The effect of the amount of iron oxide on decarburization at a constant temperature;
(3) The effect of the temperature on decarburization when packing material is used;
(4) The effect of various oxidizing materials on decarburization when they are added to iron oxides.
After these effects were thoroughly examined, the author annealed several test pieces of white cast iron of same material in a large furnace with and without packing material, and tested the annealed pieces in these two cases. The effect of decarburization upon the tensile strength and the tenacity was also studied.
Finally, the author measured the thermal conductivity of several packing materials and recommended an ideal process of annealing white iron castings for the production of black heart malleable iron.

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