Claude le Lorrain (1600-1682) - French School
Perhaps the most important landscape artist in France. Learned and worked in Rome where he imported  his exquisite atmosphere and feeling of light in his  wonderful landscapes.
 

Richard Earlom (1743-1822) - English School
One of the finest mezzo tint artists ever. A technique for the engraving of washed master drawings he brought to perfection.
 

 View of the Sea, with an effect of the sun. Claude himself is seen drawing on the shore

 

Ditto, with mount Parnassus and the Muses, the River Helicon personified, under the Character of a River God below.
 

A Landscape with an adjoining Sea View

 LIBER VERITATIS
Was a group of landscape drawings done by Claude Lorrain who are for a great deal in the possession of the court of Great Britain.The group of mezzo tints done by Richard Earlom was his first major work. It was published in 1777 by John Boydell. Measures 8.30 by 10.30 inches in a larger sheet of laid paper. Condition is perfect with a good sharp impression, a marvellous tonality and very sharp clear plate border impression still with occasional blur.
 

Mezzotint:
This technique of engraving was invented in 1642 by Ludwig van Siegen. The whole surface of the plate is first made rough by an instrument and then the artist works his design in the plate by wiping out the rough area's more or less to become more or less white area's. This technique builded up a reputation in the 17th century but is above all a technique of the eighteenth century. It was especially a spatiality of the angel Saxon world. Mezzotint prints fetch higher prices because of the picturesque view (like painted) and the more labour-intensive method to make them. It was also called "a la maniere noire"