Cornelis was a very successful entrepreneur and that allowed him to become one of the most important art collectors from the Netherlands. Besides collecting drawings he was also interested in the scientific aspect of print making and experimented constantly in seeking new techniques to make etchings in a drawing alike style that reproduced his important collection. He experimented with printing in colour from several plates. He can be called a real inventor and brought the technique of printing to a new level. His working methods have been revealed by Th. Laurentius and catalogued in the work 'Cornelis Ploos van Amstel' Kunstverzamelaar en prentuitgever, published in 1980.

He worked with other printmakers who were obliged to keep the newly invented techniques secret. Some of his assistants include Bernard Schreuder, Elisabeth van Woensel, Cornelis Buys, Cornelis Brouwer. His printer was Johannes Körlein. Son-in-law of Cornelis Troost

 

DUTCH VILLAGE Reference: Undescribed in Van Huffel                               10,20 by 18,20 cm No reference found Design: Rembrandt Haremsz. van Rijn (1606-1669) Technique: Print (?) drawing (?) with hand colouring. Thin paper pasted on another paper. Inscription: on the backside Rembrandt,   P i P late (Personal Plate?) Gift from the late Mr Finwley

ZITTENDE MAN Jonge man met hoofd in zijn hand Sitting man sold Reference: Laurentius 75. Wurzbach 10          22,80 by 16 cm Rijksmuseum Amsterdam Inv. RP-P-1882-A-6771 Signature in pencil on backside : J Cootwyck Fecit (original own handed signature) Design: Rembrandt Haremsz. van Rijn (1606-1669) Engraver: Jurrian Cootwyck ( 1714 - died 1798) Technique: Aquatint in brown and grey. Hand coloured proof state.