Geographical and geological discriptions, together with the historical reviews of the volcanic activities since 9th century of the Mt. Yake-yama (Yake: to burn, yama: mountain) in Niigata prefecture are given Logarithmic equations representing the curves of the vertical sections of the mountain are numerically given. The temperature of the fumarole at the height of 2200 metre above the sea-level, is measured and found to be 99.1°C. The greater part of the fumarole gas is water vapour (as much as ca. 97%) and among other constituents of which carbon dioxide predominates the proportion of H
2S to SO
2 is determined: the gas is passed immediately into the aqueous suspension of CdCO
3 or ZnCO
3 and the resulting sulphite and sulphide are separated and analyzed gravimetrically as BaSO
4 respectively. The percentage composition is found as follows: CO
2 89.6; N
2 3.7, H
2S 5.4, SO
2 1.1, O
2 0.3; CO, CH
4 and CnH2n nil. The activity of this volcano seems to be in the course of decay.
抄録全体を表示