The four methods of approximate calculation of mean value of the product of f (x) φ (x) where φ (x) is a known integrable function of x,
The practical methods of calculating the mean horizontal candle power are shown.
The various methods of determining the mean spherical or hemispherical candle-power and total lumen from vertical distribution curve are shown and it is described which kind of the above described! methods of approximate calculation of mean value of the product of f (x) φ (x).
Then a new method of calculation is proposed by the present author which may be called “axial mean method.”
By this methed, the intensity is to be measured in such direction as the mean hemispherical candlepower is to be calculated by Gauss' Equal coefficient or other like methods with lamp axis. Russell's (Bloch's) method or Macbeth's when flux paper is but this second rectangular axial mean. It is clear that the mean with Gauss or equel coeff. axial mean method gives for more accurate value that with rectangular axial mean method.
By these axial mean methods we can also get the mean zonal flux or the mean spherical candle-power with rapidly varying distribution.
Simple equations to determine the mean hemispherical or spherical candle-power are given and again two new simple equations are proposed which may be a little more accurate than and as quickly as any of the existing simple equations.
As for the latter, the directions in which the measurements are to be made are the same with those of Bloch's simple equations, The accuracy with those existing methods and axial mean methods are compared for such distirbutions as they vary with sin θ, |cos θ| |sin2 θ|, and E (sin θ) respectively.

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1. An investigation on the light given out by candles was conducted as to thetiintensity, light distribution, performance, spherical reduction factor, and lighting costs.
2. An ordinary candle has an intensiiy from 0.5-1.2 c.p., which is independent of its size.
3. The spherical reductor is about 1.0.
4. The lighting cost is about one sen per candle-hour; that is about 30-100 times the clectric lighting cost.

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The effective show-window trimming greatly depends upon the lighting of the window. However, at present, the lighting and the decoration are going on the parallel line, but finaly they must be united in one.
The object of this short writing is to advocate the neccesity of the unity of lighting and decoration.

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