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mal, Vegetable, and Mineral Kingdoms. 
In an undertaking of this kind, the great- 
est accuracy being absolutely necessary, 
neither time nor pains have been spared 
to render it as perfect as possible ; and it 
being also of the first importance, that 
the colours should neither change nor 
fade, from long practice and many expe- 
riments, the author has ascertained that 
his method of mixing and laying on co- 
lours will ensure their remaining con- 
stant, unless they are long exposed to the 
sun, which affects, in some degree, all 
material colours ; he has therefore ar- 
ranged Werner's suites of colours, with 
his own additions, into a book, and in 
