THE LADIES 7 MAGAZINE OF GARDENING. 
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spot of black, and then to fix them on a spot of red, when a dim circle of 
green, the complementary colour to red, will be seen round the red spot. 
In the like manner, the complementary colour of purple will be found to 
be orange, and of blue, yellow. 
It has been long known that there is in matter generally a principle of 
attraction, and another of repulsion; and in colours there is also a prin¬ 
ciple of union, and another of opposition. The art of the landscape- 
painter, the florist, and the landscape-gardener, as far as colours are 
concerned, consists in the employment of unions and contrasts, so as to 
produce harmony; and in a particular exaggeration of the one or the 
other, so as to add to harmony, expression, or character. 
All colours, considered philosophically, are contained in light in a state 
of combination. This combination may be dissolved, or decomposed, by 
means of a portion of crystal glass, of a triangular shape, which is called 
a prism. When the rays of light are made to pass through this prism, 
they are found to resolve themselves into three simple colours, viz., red, 
yellow, and blue ; and three compound, or intermediate colours, each 
formed by the union of two primitive colours, and making purple, green, 
and orange. 
To these some add violet; but this seems unnecessary, as by means of 
reds and blues, mixed together, are produced all possible shades of purple ; 
by means of blue and yellow, all possible shades of green; and by the 
mixture of red and yellow, all possible shades of orange. 
Hitherto I have said nothing of black or white; which, for all practical 
purposes, whether in painting, floriculture, or landscape-gardening, may 
be considered as colours, though with reference to science they are not so; 
as black is produced by the absorption of all the rays of light which fall 
upon any surface, and white by the reflection of all these rays of light. 
Of course, in neither of these cases can there be any colour, because colour 
can only be produced by the decomposition of light. 
In speaking of the disposition of colours, I shall first say a few words 
on the colours properly so called, and next on the disposition of black 
and white. 
The grand principle in the employment of colours in quantity, or in equal 
quantities, is never to employ a compound colour between the two 
primitive colours which compose it. For example, purple ought never to 
be employed between blue and red ; green between blue and yellow ; or 
orange between yellow and red: but each primitive colour should be 
contrasted with its complementary one, which will always be found to be 
a compound one. Thus red is a primitive colour, but green is a compound 
one ; yellow is primitive and purple compound; and blue, primitive and 
