BEAUTIFUL BOOK MAKING 
by the action of a solution of tin. This was ex- 
tremely costly. This purple is very enduring, 
though so are the pale blues and the lilacs in spite 
of the fact that these colors containing blue so often 
fade early in modern work. The Irish illuminator 
and his teacher had evidently quite exhausted the 
knowledge of pigments in relation to their tints and 
enduring qualities. 
Wendell Phillips’ well known lecture on “The 
Lost Arts” called attention to a number of inven- 
tions made in the olden time, lost subsequently and 
since not rediscovered in spite of their desirability 
and our pride in our success as inventors. The best 
illustration of one of these is the colorings of the 
Book of Kells. Our illuminators find it quite im- 
possible as a rule to put colors on parchment that 
will endure in their original tints even for a hun- 
dred years much less a thousand. In spite of the 
investigation that has been devoted to it, there is 
as yet no absolute certainty as to the colors used, 
and the mode of preparation which gave them such 
wonderful durability is still a profound secret. Pro- 
fessor Hartley spent much time at the subject and 
gave his conclusions in a paper published in the Pro- 
ceedings of the Royal Dublin Society, New Series, 
Vol. 4: 
“A very careful examination of the work shows 
that the pigments mixed with gum, glue or gelatine 
are laid on somewhat thickly—there is no staining 
of the vellum and no mingling of tints. There is 
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