The relation between the condition of the rammed sand and compressive strength, permeability, water content, the ramming number and the weight of the test piece is investigated.
  To show the condition of the rammed sand we use a rate of height H ⁄ h, H is the height without the space among the sand grain and h is the measured value.
  We obtained the next results ;
  ① H ⁄ h  1−C log₆ φ
    C : const.  φ : permeability.
  ② The height of the test piece h and H ⁄ h have an important effect to compressive strength.
  ③ Compressive strength is inversely proportionate to permeability.
  ④ Water content is one of the most important factor of H ⁄ h.

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  When we use the oil sand core, we have not coated on its surface. But in this case, various troubles have happened. So we coated on the oil sand core for preventing the blow hole chiefly in the bore part of Datsun cylinder block. In this report we mention the experiment of 23 kinds of coating materials. With the result we recognized that the following coating material is best in regard to the coating method, casting condition and machining condition.
  ① Graphite (Soil) 90% + Molasses 10%
  ② Graphite (Soil) 90% + Clay (Shimizu) 10%
  ③ Graphite (Soil) 90% + Bentnite 10%
In each case, we have used as 100% H₂O Solution.

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  In a sand casting of aluminium, the relations between the sections of the gate, the runner and the sprue is discussed by measuring the metal flow in a particular way. The results obtained are as follows :
  (1) Metal flows generally with free surface in a runner not filling it up.
  (2) If the sectional ratio of the gate to the runner is large, metal is ready to flow into a sprue nearer to the end of the runner, but when the ratio is small, it is apt to flow into a sprue nearer to the gate.
  (3) In the casting with many sprues, metal flows uniformly into all the sprues if the sectional ratio of the gate to the runner has some limited value between 0.6∼1.7.
  (4) If the total area of the sprues is ¾ of that of the runner, the metal flows into them filling all the sections.
  (5) The adequate ratio of the sections of the gate, the runner and the sprue gotten from the present investigation is 0.6∼1.7 : 1 : 0.75.
  (6) If the section of the runner is lessened step by step, metal flows filling all the sprues though they have different ratios of sections mentioned above.

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  In a sand casting of aluminium, the weak current is led to a flowing metal and the terminals are inserted at several points in the mould. If the flowing metal touches the terminals, it is indicated by the lamp in the circuit and is recorded on a paper with time scale.
  Thus the flow of metal in plate, in ring and in quadrilateral is measured and discussed.

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  Inspecting a stratum of the west coast of Ise Bay by documents and by an actualiservey, the author inferred the occuring cause of layers of green sand in the neibourhood of Tsu and at the southern part of Sima Peninsula, and showed a help of development of green sand. (M. I.)

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  The characters of Sima-Sand and Tsu-Sand which the author discovered were inspected. The results obtained were as follows :
  Sima sand No. 1 is uniform in grain and has the best characters, which is, if added Bentnite etc., improved to become a remarkable material of synthetic sand. Grains of Sima-sand No. 2 and 3 are not uniform a little. Sima-sand No. 2 is coarser in grain but No. 3 is more fine.
  Tsu-sand is worse than Sima-sand. Tsu-sand No. 1 is too fine in grain to use and Tsu-sand No. 2 is generally available.
  The difference of grain distribution was recognized by the position of the sand stratum, and has a certain tendency, by which uniform sand in grain can be obtained. (M. I.)

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  In the operation of a cupola, the blast enriched 4% oxygen was practiced for four minutes      (a) shortly after the beginning of the blast,      (b) shortly after the first tapping,      (c) shortly after the beginning of the blast and the first tapping, and      (d) when the tapping temperature became lower during the operation. The results were as follows :
  (1) The time from the beginning of the blast to the tapping was shortend and molten metal of a high temperature could be obtained from the first tapping.
  (2) The melting speed was fastened.
  (3) When oxygen was enriched during the operation, the tapping temperature became 10∼30°C higher and was kept more than 30 minutes.
  (4) The characters of material did not become worse by the enriched oxygen in the case of the coke ratio about 15%. In the coke ratio less than 12.5% molten metal was oxidized a little and therefore the enriched oxygen can not be available for save of the coke ratio. (M. I.)

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