( 392 ) 
[June, 
ANALYSES OF BOOKS. 
The Theory of Colour in its Relation to Art and Art-Industry . 
By Dr. Wilhelm von Bezold, Professor of Physics at the 
Royal Polytechnic School of Munich, and Member of the 
Royal Bavarian Academy of Sciences. Translated from the 
German by S. R. Koehler, with an Introduction and Notes 
by E. C. Pickering. Boston : L. Prang and Co. London : 
Triibner and Co. 
We have here a thorough and masterly exposition of the laws of 
colour as applied to industrial and artistic purposes. The author 
has most important lessons to convey, not merely to the painter, 
but to the tissue printer, the dyer, the paper-stainer, the uphol- 
sterer, the manufacturer of glass and porcelain, the worker in 
mosaic, and the jeweller, all of whom will find here valuable 
principles laid down for their guidance. Natural good taste and 
what is called a quick eye for colour will doubtless do much, but 
without distina and systematic knowledge they will frequently 
fail to save their predecessor going astray. It may even be 
suggested that the propensity for sombre, dull, and impure co- 
louration in modern costumes is to be traced to ignorance. 
Fearful of the wretched effeas admittedly produced by the im- 
proper combination of pure colours, we take refuge in a general 
murkiness, which at any rate makes our failures less conspicuous. 
A work like the present may therefore justly claim a very high 
industrial, artistic, and social-aesthetic importance. 
The author naturally opens with an examination of the phy- 
sical basis of the theory of colour, involving, of course, a descrip- 
tion of the spearum. Here he explains very clearly that great 
stumbling-block to numbers of even well educated persons — the 
essentially subjedtive character of colour. He also takes an 
early opportunity of pointing out the distinction which exists be- 
tween colours and pigments. If we mix together a yellow and 
a blue pigment,— say gamboge and ultramarine, — or if we dye a 
piece of silk with indigo and then top it with weld, we obtain, as 
all the world knows, a green. On the faith of this and similar 
experiments it was decided that green is a compound colour, and 
that the only simple primary colours are yellow, red, and blue. 
The reason, however, why green is produced by the mixture of a 
yellow and a blue pigment is not difficult to trace. The light 
passing through them undergoes what may well be called a pro- 
cess of subtraaion. Suppose we pass light through Prussian 
