Liber veritatis, or, A collection of two hundred prints after the original designs of Claude le Lorrain in the collection of the Duke of Devonshire, / executed by Richard Earlom in the manner and taste of the drawings ; to which is added a descriptive catalogue of each print, together with the names of those for whom, and of the places for which the original pictures were first painted, (taken from the hand-writing of Claude le Lorrain himself on the back of each drawing) and of the present possessors of many of the original pictures.

"These drawings were called the Liber veritatis, and were made for the purpose of identifying the real works of Claude from others said to be from his hand. These engravings are executed in imitation of the original drawings, and printed in a warm bistre colour ... They were at first produced only in outline ... The demand was so extensive that Boydell caused Earlom to retouch and refresh the plates five or six times ..."--Dict. nat. biog., under Earlom. The original drawings passed from Devonshire to the British Museum in 1957.
Title page of v. 3 reads: Liber veritatis, or, A collection of prints after the original designs of Claude le Lorrain in the collection of His Grace the Duke of Devonshire, Earl Spencer, Richard Payne Knight, Benjamin West, P.R.A., Charles Lambert, Edward Turnor, George Gosling, and Joseph Farrington, esqrs., executed by Richard Earlom ... . London : Published by Hurst, Robinson, and Co., Successors to messrs. Boydell : Printed by Thomas Davison, Whitefriars, 1819.
Vol. 3: Plates 1-40 only (of which no. 5 is missing); t.p. missing; cover-title for no. 1 (plates 1-20) dated June 4, 1802.
Proof impressions before the plates were cleaned; plates 1-30 are printed in black ink. Plates 17 and 18 in duplicate.
Copy 1 (PML 11740-42 is copy 2).