The method of fluorescent lamp lighting for interior of electric car on direct current source, instead of alternating current, is the simplest and the most convenient.
Especially, it is a gospel for electric car which has no motor generator itself, to find an efl'iicient lighting method with trolley as electric source.
The grid type fluoresecent lamp and its series operating circuit group, whicn were devised for these purposes, are in use for about 200 cars, and obtained very good results.
Described in this article, are various characteristics of this lamp, series operating system, and dark end effect which is peculiar to direct current operation, as according to our experimental esults.

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In this paper are described the two types of color and gloss meter which have newly been developed with fundamental improvements on the older type. The principal points of improvements lie in the fact that two types, the one precision type and the other simple type, are developed instead of one older type.
Though the precision type (Hg. 1) is operated in somewhat more complicated way than the older type, it has many advantages as follows:-
(1) Tristimulus values of reflecting or transmitting colored objects can be measured directly by use of four filters which satisfy Luther condition. Therefore, they are not subjected to Van den Akker' stheoretical errors, as those measured by three filter colorimeters.(cf. Figs. 7, 9)
(2) Gloss is indicated in 45°-45° or 60°-60° specular reflectance, which is substracted by diffuse reflectance automatically. In this measurement angular apertures of the measuring beams can be adjusted on ocasion at +1.5°or±7.5°, so that gloss intensity and distinctness of image, which represent two aspects of gloss, are separated numerically.(cf. Fig. 10)
(3) The performance of the instrument is improved by making use of embedded selenium photocells.
(4) Values of color and gloss are measured to three decimal places by the modified Campbell-Freeth circuit.(Fig. 3)
(5) The photoe-lectric ac voltage stabilizer (Figs. 4, 5) in the instrument supplies the lamps with constant voltage independent on the line voltage and frequency.
The simple type (Fig. 11, 12) is composed of a search unit of only 650 gr. and a electric measuring instrument. It can measure 0°-45°(red, green, blue and luminous) reflectances and 45°-45° specular reflectance.

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