The petroleum engines have been popularized after the war as an agricultural implement especially for cultivation of land and grain cleaning.The brief classification, power and use of the recent engines are given.The improved points of the petroleum engines are listed which have evidently promoted their spread in the farming.
The authors assert the theory of coal formation from cellulose, against Fischer's theory of lignin origin, by the grounds of “artificial coal” experiments; (1) the oxidized product of the arificial coal from cellulose by permanganate shows the evidence of mellitic acid, (2) the cellulose coal has a lignin-like part by the usual rational analysis and (3) the artificial coalification of the mixture of lignin and cel-lulose suggests the mutual reactions during coal formation process, i.e., the expected importance of the composition in the vegetable debris as the original substance of coal formation.
A historical survey of the petrochemistry in the United States is pre-sented with detailed descriptions of the properties of the petrochem ical products as well as recent consumption, of raw materials and producing capacity.A brilliant fu-ture development is expected of the petrochemical products which have already taken important parts in the organo-chemical industry.Its applications to the Japanese industry are, however, to be circumspectly considered mainly for the point that the postwar situations of Japan's petroleum industry are apparently different and back-ward from the countries referred in this review. The author's project of the possi-ble development in Japan is suggested.