As one of distinct phenomena after the world's war, electric heating, both industrial and domestic, has become to play very important situation in the electrical field.
Especially, in this country, a custom of using wood and char-coal for cooking and heating purpose and burning it without any chimney will accelerate its progress and development from the view of sanitary and economical point.
By the writer's own experiment and estimation, describes that the load factor of central station shall not be lowered by increasing heating load.
Refering to European system of rate of Electricity, gives a hint how to fix up the rate system in order to have better load condition of central station.
In the last part of the present paper, describes two water heaters good for improving the load condition, and the result of experiment of deterioration test of heating element.

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Keihm Denryoku K.K. succeeded in his hydro-electric power development at Azusa River in the Shinano Province in Feb. 1923.
This developed power is transmitted at 154K.V. from Ryushima Generating Station to Yokohama receiving station at Totsuka, near Yokohama, 125 miles away.
154K.V. is the highest transmission line voltage in Japan, and our transmission line was the first to place in operation.
This paper describes the brief description for our company's system at first, and then a considerable detail description for official and private tests of transmission line, as the transmission line is the element of greatest importance in satisfactory operation, although there are many features of the engineering interest in the generating and receiving parts of the system.

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Three kinds of transmission losses at the junction point of two circuits having different impedance, i.e, transition loss, argument loss and transformer loss are explained, and the ideal transformer which minimizes these losses is such that its primary and secondary impedances are in conjugate to those of the circuits respectively, On this principle, the methods of determining the terminal impedances to get an ideal circuit when these are connected to the terminals of any type of circuit, and designing an ideal transformer which makes the circuit ideal when it is inserted at the junction point of two given circuit of different impedance are described.

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An electro-dynamic loud speaker tested is described in details. The impedance characteristics of the active coil are found to be just the same as for ordinary telephone receivers. Damped or stationary and motional vector impedance graphs are respectively a straight line and a circle when the frequency is varied But the diameter of motional impedance circle coinsides with the resistance axis, which or ordinary receivers is usually depressed downwards from it. The diameters are 74.0, 194.0 and 290.0 ohms, respectively for the d. c. excitation of 0.5, 1.0 and 1.5 ampere and without the trumpet. The resonance, first and second quadrantal frequencies are respectively about 620 _??_, 616.5 _??_ and 624 _??_ for 1 ampere excitation. Variations of these frequencies for different excitation are very small. And the force factor for 1 ampere excitation is 9.64×10⁶ dynes per absampere.
When, however, the trumpet is on, the motional impedance graph is reduce to about 1/16 of the size when it is off, which means little distortion of the diaphram motion for the reproduction of speech although the system without the trumpet has a marked resonance point; and the graph is accompanied by a number of small loops, because the trumpet is a multi-resonance system.
Advantages of this instrument for acoustic impedance and similar measurements are explained. The action of such a vibrating system as inductance or capacitance is also pointed out.

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The flux distribution along the air gap in electric machines with open slots is investigated experimentally by electrodynamical method for the case:-
(1) With slots on one surface only, and
(a) infinite tooth permeability.
(b) constant tooth permeability.
(2) With slots on both opposing surfaces, and infinit tooth permeability. From the results obtained, the writer has established an experimental formula for air gap correction factor, and compared with formulae proposed by many authors hitherto.

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