The Nisiazuma sulphur mine is situated on the north side of Mt. Nisiazuma, rises on the borders of Fukusima Prefecture and Yamagata Prefecture.
Mt. Nisiazuma is a strato-volcano formed of two pyroxene-andesite-lava-flows and pyroclastic rocks, such as tuff, tuff-breecia and agglomerate etc., erupted through granite base and Tertiary formation.
The Nisiazuma deposit is an impregnated sulphur deposit of Numajiri-type, that is composed of many ore bodies, distributed in the above mentioned pyroclastic rocks.
In the pyroclastic rocks, there are some brown colored seams of shaly-tuff.
This brown color is caused by organic matter, so that the writer supposes that these shaly-tuff are sedimentary products of swamp in the dormant stages of volcanic activity.
Such sedimentary seams of swampy nature are not only found in this deposit, but also in the deposits of Yatoko, Numajiri and Matsuo.
We can suggest the conditions of sedimentation of the pyroclastic seams by following up the shaly-tuffs.
The mineralizations, especially alunitization in the Nisiazuma deposit are not so great.
The writer inferred by many phenomena that the greater part of sulphur was sublimated by solfataric action, but some part of sulphur was precipitated from the hydrothermal solution.
The grade of the ore of this deposit is about 25%-35% sulphur, but the writer presumes that the richer ore-bodies can be located on the lower levels, so that the prospecting should be carried out by boring into the lower levels.

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In this paper the authors discuss theoretically the effect of the stepped topography on the potential curves obtained by the spontaneous polarization method. The problem is, dealt as a two-dimensional one, and the Shwarz-Christoffel's transformation is used.
The results of numerical calculations are given in the form of potential profiles for two cases.

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A hot wire anemometer, the connection of which is shown in Fig 1, was designed and tested. It was shown that the errors due to variation of air temperature etc are negligible, the temperature of the hot wire is 15-45°Chigher than the temperatur of the air around, but the sensibility decreases as the air velocity increases. The velocity distributions in a working face & some other openings were determined.

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Formation of insoluble nickel compound in blister copper anode was studied, and the follow. ing conclusion was obtained as a result.
1) The insoluble nickel compound is nickel oxide.
2) The quantity of insoluble nickel increases as the total nickel content of the blister copper increases and the sulpur content decreases.
3) The quantity of insoluble nickel of anodes with total nickel content below 0.3%, is neglesible.
4) Partial elimination of nickel by overblowing followed by deoxidation with pyrite in the ladle during the pouring was tried with success in order to minimize insoluble nickel.

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