It seems this book's colours were hand-painted, but I might as well mention two famous mid-C19 examples of colour printing, when (IIRC; I am not an expert) high-quality colour printing was still very expensive and rare:

* the "Sobieski Stewarts'" dodgy Vestiarium Scoticum: https://en.wikipedia.org/wiki/Vestiarium_Scoticum

> It was from Eilean Aigas, in 1842, that the brothers at last published their famous manuscript, Vestiarium Scoticum . It appeared in a sumptuous edition limited to fifty copies. The series of coloured illustrations of tartans was the first ever to be published and was a triumph over technical difficulties. These illustrations were executed by a new process of ‘machine printing’ and, in the words of a scholar writing fifty years later, ‘for beauty of execution and exactness of detail have not been excelled by any method of colour-printing subsequently invented’.

> Hugh Trevor-Roper, "The Invention of Tradition: The Highland Tradition of Scotland"

* Oliver Byrne's colour edition of the first six books of Euclid https://en.wikipedia.org/wiki/Oliver_Byrne_(mathematician)#B...

And why not throw in Shadows From the Walls of Death https://en.wikipedia.org/wiki/Shadows_from_the_Walls_of_Deat... with its samples of intensely green arsenical wallpaper?