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mean to represent do not contain the proper quantity of each separate co¬ 
lour ; for instance, you may have a yellow flower that contains more than 
the portion of yellow you ought to admit into the group, and the question 
is, what to do with it, and not destroy the character j or beauty of the flowei 
by leaving part out. Here ingenuity must be called to your aid, for no one 
colour should predominate improperly over the others, but all be kept in 
their proper force as well as station. When I speak of this piopoition of 
each colour, I include all the variety* of tints, from the pure to the com¬ 
pound state : for when the proper quantity of light and shade is admitted 
into the picture, a very small proportion of the colours will remain in their 
pure original state; the greater part will be converted into compound light 
and compound shade tints. Besides this effect that light and shade will have 
on the general mass, it must be remembered, that every one of the prismatic 
divisions contains a gradation from a pure colour to a compound one with the 
next. The 45 degrees red contain pure red, also orange red in all its gra¬ 
dations, as do all the other divisions their gradations also ; and if this 
Spectrum is attentively observed, it will soon be seen how small a portion of 
pure colour there is in each division, that is, in each of the coloured pencils 
of a ray of light, though they go by the general titles of yellow, orange, red, 
&c. &c. and must be admitted into a picture, by the very same; yet, if those 
separate gradations are not nicely copied, and the portion of them all together 
regulated by the proportion they bear t o^one another in the Spectrum, their 
effect in a picture will be very different Tawhat it is there. I do not mean 
that there should be so many degrees of red, &c. &c. exactly as in the 
Spectrum, for it would be impossible to measure out colours that w'ay, but 
it will be easy to observe what proportions they bear to one another, and to 
let the colours in a picture have the same: for instance, there are 48 degrees 
of yellow to 27 of orange, that is, nearly double the quantity of yellow' to 
that of orange; therefore there should be the same proportion of them in a 
picture, in all the different gradations observable in the Spectrum : and the 
greatest nicety, in this, must be observed, for fear of destroying the balance 
* Which comprehends an infinite variety of other compound tints, formed by a mixture of the 
different prismatic colours with one another, that will take their station in the picture in point of 
brilliancy, according to the affinity each bears to that particular pure tint it partakes most of. 
