This was made by covering an aluminium plate with a greasy layer known as etching ground, which is baked at high temperature to solidify it into something like hardened wax. The design is then drawn through this ground using a sharply pointed scriber, a pen-like steel needle. The plate is then immersed in a corrosive solution which burns the design into the metal plate. Selective applications of corrosive solution give shading and tone. The metal plate is cleaned, to remove all traces of the printing ground, then inked, and rolled through an etching press in contact with dampened paper. The etching press exerts thousands of pounds pressure forcing the ink from the plate into the paper. You can see the impression of the printing plate "stamped" into the print.