電力統一は戦戰後經營として主要なる國策の一である。現時殆ど總ての産業は電化せられ只鐵道、船舶のみ殘て居る、是又近き將來に電化せられんとして居る。
電力統一の唱導せらるる技術上の理由は次に掲ぐる目次の如きであつて要するに動力能率な増進し、故障共助を行ふにある。
米國、獨國、英國に於てに戰時中より高調せられ現時戰後經營として益々其歩を進められて居る。
本邦に於ても大正〓年電氣事業法を改正して異事業者の送電連絡を命令し得る條項な加へ之に關する注意な與へしが、爾後電氣事業者卒先して機會ある毎に實行し、最近雜に合併が盛に行はる。
合同統一は叙上の利益はあるが、之を實行するには各種の注意を要する、否らざれば却て實行上の不便を來たす虞がある、要之に自覺あろ合同統一が望ましい、且つ合同統一を實行したならば之に依つて得らるべき利益に一般に均霑する樣務めらるることを切望する。

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米國に於ける長距離無線電信の方式は凡て持續電波式を採用し火花式は次第に減少すRadio Corporation of America はalexanderson generatorを又米國海軍はPoulsen arcを重用す

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Insulators, as used in present day practice, are a product of many years of experimenting and numerous unfavorable experiences. The art of manufacturing has been so perfected that a rate of depreciation of less than 1/50th of one per cent per annum had been reached. The insu'ating materials in present use are of two classes, hydro-carbons and silicates. The latter, which includes glass and porcelain are used for outdoor service, but glass because of its characteristics is little used.
Porcelain used in American practice is made up of clay and potash feldspar, which acts as a binder. Great deal of attention must be paid to proper firing adequate vitirification, purity and fineness of raw materials, factory organization, etc. in order to produce a uniform grade of porcelain of high quality. The manufactured porcelain insulators are all given an electrical potential test to weed out the defective ones. The test usually consists of applying high frequency peak voltage many times over flashover value at normal frequency.
There are now three types of porcelain suspension insulator used extensively interlink, tension and cap-and-pin types. The last named type as used in overwhelming numbers because of its superiority both mechanically and electrically over the other two. It is now generally believed that with the increase in the voltage of transmission lines, this type will be more extensively used.
In many systems, grading of insulators is resor_??_ed to. Theoretically, grading will equalize the voltage duty among the several units of the string, but in service, it has been borne out that grading takes care of only one condition, namely with the insulators dry and clear. Additional objections in adopting this method are increase in first cost and in the maintenance cost. The most common practice today is to make the insulator nearest the conductor large enough to withstand the stress and make the rest of the same size. This will be cheaper from manufacturing standpoint as well as from the standpoint of keeping spare units.
There are two factors which governs the selection of number of units per string, namely the distance from conductor to cross arm and rate of depreciation of insulators. The first item is well understood but the last factor could be only approximated by the use of law of probability. Austin and Klanber's formula appearing in the Transaction of the American Institute of Electrical Engineers seems to give pretty close results.
After the insulators are put in service, at certain intervals, insulation tests are sometimes carried out to determine their condition. Three methods of testing are in common use, megger, “buzz stick” and spark coil. The megger method is most widely used and is quite efficient, but this and the spark coil mothod require the line to be taken out of service. At the present time, there seems to be no satisfactory method of testing pin type insulators. Visual inspection and the use of telephone receiver in the case of wood poles are the only methods at all effective.
The use of ground wire is a much debated question today. Many new lines installed recently did not put in the ground wire on the ground that better results will be secured by putting its cost into additional insulation.
The practicability of using wood poles with suspension insulators is also under study. In using wood poles, the rate of decay of wood must be balanced against the element of cost. In a certain instance, a 110, 000 volt line was put in with wood poles but the result of operation has not yet been made public.

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叙説に於て歐米に於ける自働電話交換機發達の状況並に其の種類に就て概説し現今實用せらるゝ自働電話交換機がストロージヤー式及ウエスターン、エレクトリツク會社のロータリー式、同パネル型スヰツチ式の三種にして前二者に生として二三千名の加入者を有する中小都市に適し後者ば大都市に適するものなることを叙述し。
本論に於てパネル型スヰツチの働作の詳細な説明する爲め先づウェスターン、エレクトリツク會社が自働電話交換機を完成するが爲め其各部に就て研究の結果先づ半機械式交換機の數種を設計實用したるより全機械式の内容な解説するに便なる爲め専ら半機械式交換磯の詳細を(一)交換機座席構造の概要、(二)一般接續の順序、(三)各部機械の説明、(四)諸回路の働作み數項に分ちて説明したる後全機械式交換機の概要な述べ。
結論に於て自働交換機と手働交換機のサービスに與ふる影響及優劣並に經濟上の比較を實例を擧げて説明したるものなり。

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三相誘導電動機の固定子に三相交流な送り、之れに依つて生ずる廻轉磁界を利用して、直流を取り得るならば、之れを以て一種の變流機とすろことが出來る。筆者は之れに就いて考案を廻らした結果、前記固定子の内側に、直流機の電機子を靜止させ其の周圍に刷子を同期速度で廻はす方法を取つた。又正員兩刷子間の電位差が常に最大になろ樣に、自動的に刷子の位置を調整せる工夫を案出した。本編は其の詳細の作用を説明し、尚ほ其の設計上考慮すべき諸點な、微分方程式に依つて研究したものである。筆者は此の特種變流機に關し特許を得た。

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