The North-Eastern district of the Main Island is the most important sulphur region in Japan. The type of sulphur deposits falls into four -general classes: sublimation deposit, sulphur lava, impregnation deposit and sedimentary deposit. Among these, the sulphur bed of the Matuo Mine and the impregnation deposit of the Numaziri Mine are the chief productive ones.
.The present states of mining as well as the future prospecting has been discussed in detail.

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As a method of underground main haulage, an engine plane is both widely and on a large scale adopted in Japan. This usage is considered one of the characteristic aspects of colliery practice in Japan.
In this paper, the author presents the practice of designing the engine plane, especially simple engine plane, by the nomographic calculation to acquire ease and promptitude in designing.
As prevenient elements in the consideration, he treats the stability of a tub on inclined plane for the following cases;
(1) tub at rest or in uniform motion in a straight line.
(2) tub, accelerated.
(3) tub, over an obstacle.
(4) train of tubs, on varied grade.
On varied grades such as are inevitable in practice, the front-wheel of the first tub in a train sometimes runs risks of derailment. This unavoidable condition is dynamically explained and a formula, by which the number of tubs in a train is restricted for the sake of safety, is deduced by the author.
The value of coefficient of friction is accepted as 0.035 totally for rope and tubs, and it is demonstrated that this value is sufficiently safe and is not over-large.
In connection therewith, it is accentuated that the expensive installation of ball or roller bearings for tubs is not beneficial economically for the general condition of mines, and especially for the engine plane it is almost nonsense that the coefficient of friction is altered corresponding with the kind of bearings.
Empirical formulas are deduced for J E S No. 281 “Wire Rope for Mine Use” in respect of diameter, strength and weight for every class.
Substituting these empirical formulas, another formula by which the diameter of wire rope is decided with regard to the expected factor of safety, is derived and then represented on Nomogram I.
It is assumed that the ratio of the weight between an empy tub and coal is 0.5, and if R≠0.5 the multiplier for correction is applied to W (weight of coal hauled per trip).
The multiplier is represented in the form of a special chart for convenience.
Moreover, if it is desired to alter the coefficient of friction in using nomogram I, the angle of inclination is to be changed slightly because sinα+0.035 cosα≈sin (α+2) with reference to the relation between coefficient of friction and angle of friction.
Other nomograms are also designed and presented, for a simple engine plane.
Nomogram II maximum pull.
Nomogram III velocity of rope.
Nomogram IV required horse power.
Nomogram V capacity per hour.

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in the previous report the authors had introduced the method, which determines the algebraic sum of the principal stresses in metals by X-rays. But, as it was not sufficient with this method, here has been' demonstrated the more important method, which determines the component of the internal stress in any direction, and moreover the directions of the principal stresses and their quantities, by means of projecting the X-ray beams rectangular and oblique to the surface of materials respectively; and it is remarkable, that it needs not to know the normal lattice constant in the stressfree state, by using this method. According to the results of the experiments by the authors, various steels have had different lattice constants, therefore it has been recognised that the latter method is necessary, when the X-ray method is applied for the practical testing. The authors had also investigated the relation between the tensile stress and the lattice spacing about mild steel, and obtained some desirable results.

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