The Auther intended to improve the properties of high grade Cast iron by the cooling and heat treatment process. The results of experiments are as follows.
1. The greatest strength of cast iron is obtained when the graphite is very fine and the matrix contains neither free cementite nor free ferrite, but is entirely pearltic. ie. Eutectic cast iron has the greatest strength.
2. Gray Cast iron when subjected to cooled relatively rapidly is obtained a structure as like as eutectic and fine graphite, but is more or less hardly.
3. So When heated 850°C for 3 hours, the cast iron has reduced hardness and produced very fine graphite and matrix of pearlite.
4. And it can be obtained high strength and toughness.
5. The authur named Taniable cast iron for the cast iron, and the composition is as follows.
C 2.5-3.0 Si 1.0-2.0 Mn 0.3-1.0 C+Si 4.0-4.5

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In the first report, the authour described on the thermal conductivity of white and gray cast irons making chilled Rolls. It was an important thing to calculate the thermal stress induced in the roll and to consider the other heat relations on the roll, the ingot making practice and the internal combustion engine. From the result of the former experiment, it was seen that the thermal conductivity of cast iron was much influenced by the microscopic structure than by the chemical composition.
In this paper, he reports on the results of the thermal conductivity measuring on gray cast irons of various chemical composition with the same apparatus as that was described in the first report. The temperature range experienced extends over the ordinary temperature to about 800°C and the chemical composition of specimens is varied as follows:
1. Carbon Series; four specimens whose carbon contents are varied from 2.5% to 3.69%.
2. Silicon Series; five specimens whose silicon contents are varied from 1.42% to 3.84%
3. Phosphorus Series; Six specimens whose phosphorus contents are varied from 0.108% to 1.156%.
The thermal conductivity of cast iron is much affected by the microscopic-structure as shown in the first report, hence he measured it first on the specimens as cast in which remainned some pearlites, and then on the annealed one whose structure is consisted of the graphite flake and the ferritic matrix, that is convinient to see the effect of the chemical composition on the thermal conductivity.
It will be seen from the result of the experiment that the thermal conductivity of the well annealed gray cast iron is gradually decreased as the contents of carbon, silicon and phosphorus are increased, although the rate of the influence is not the same on each element; and also that the influence of the microscopic-structure on the thermal conductivity is much larger than that of the chemical compositions.

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