In order to investigate the reaction of sulphur or sulphur compounds with several metals and alloys at high temperatures, Armco iron, carbon steel and gray cast iron were at first used. The specimens were heated at various temperatures ranging from 300° to 900° in vapour of sulphur for different periods of time up to 240 hours' and the thickness of sulphide layer formed on the specimens was measured. The thickness of the sulphide increases with the rise of heating temperature and the increase of reaction period, though the rate of formation differs according to metals, i. e. Armco iron is the most rapid and gray cast iron is the most sluggish of the three used in the present experiment.
The thickness x of the sulphide layer formed is expressed by an equation, x²=kt, in which t is the reaction time and k, a constant. Between the reaction constant k and reaction temperature T°K, the following relation exists, log k=A+B/T, in which A and B are constants, that are nearly unvariable in temperatures below and above the transformation point of specimens, the boiling point of sulphur or the peritectic point, FeS+S_??_FeS₂. The sulphide formed on the surface of specimen consists of two layers; the composition of these layers correspond nearly to the formula FeS, though the sulphur content is slightly less in the inner layer than in the outer. From the result above described and that of microscopic examination, a mechanism of the formation of sulphide is proposed.

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The distribution of internal stress and the energy of residual strain in cold-drawn bars of copper, phosphor bronze, brass and carbon steel, drawn with conical dies of two types A and B, were measured. The work-done required in drawing were also measured, and the relations between these values and die angle were obtained. The die of A-type has a circular cylindrical part under its bearing part, and that of B-type no circular cylindrical part.
In general, the outer portion of cold-drawn bar is under tension, while the central portion under compression. But it is not always true, and the distribution of internal stress in some metals becomes more complex by the type and the angle of die.
In all metals, the values of residual forces in the bars drawn with A-die are smaller than that drawn with B-die, and in both cases they increase with the die angle.
The work-done required in drawing with A-die is greater than that with B-die. As the die anlge increases, the work done decreases up to some angle and reaching a minimum value, but beyond this angle it increases with the increase of angle, excepting phosphor bronze and carbon steel bars drawn with A-die. In the fomer metal the workdone decreases with angle and in the later one it is opposite.
The energy of residual strain in all metals drawn with A-die is smaller than that with B-die, and in both cases the energy increases with the die angle.

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An investigation has been made of the influences of added metals, such as Al, Si, Fe, Mn, Zn, etc. on the properties of Phosphor bronze.
The tests have shown that the mechanical properties of Phosphor bronzes containing small amounts of Al and Si (about 0.5% each) are distinctly higher in strength than that of Plain Phosphor bronze, and that the addition of few percent of Fe or Mn gives still more excellent hot-working characteristics.
The following table shows the results of tests made on some ordinary and modified Phosphor bronzes._??_
The tensile and elastic properties of Phosphor bronze strip in direction parallel, normal, and at 45° to the rolling also have been determined after progressively increasing rolling reduction up to 70%. When the rolling reduction has been sufficient (about 30%) to induce a directional effect, the greatest tensile properties are obtained normal to the rolling direction, but bending properties are least.

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Sowohl bei gewöhnlicher als auch bei sehr langsamer Durchführung des Zugversuches mit dem zylindrischen oder prismatischen Stab aus dehnbaren Metalle verformen sich die Kristalle anfangs elastisch, dann plastisch, in weiteren Verlaufe bildet sich eine örtliche Einschnürung aus. Im Einschnürgebiete wurde der Stoff überhaupt voll plastisch und die Verfestigungsfähigkeit der Stoffes danach eine Funktion der Verformung. Am zweckmässigsten soll die Verfestigung berücksichtigt und die Form der Einschnürung als Hilfsmittel benutzt werden. Die auf einen System der Massen bewegung in der Umgegend der Einschnürteils gefundenen ebenen Bedingungsgleichungen führen zu der Stromfunktion. Durch Transformation der Spannungsgleichungen im rechtwinklige Koordinatensystem auf die Hauptspannungstrajektorien und ferner mit Berücksichtigung der Verfestigungsfähigkeit, können die Hauptspannungen direkt gerechnet wurden. Für die verhältnismässig hochschmelzende Metalle, z. B. Kupfer, Flusseisen, Armco-Eisen, wurde die Grundlage des Bruches durch die Spannungszustände zwanglos geklärt.

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