This is an engraved copper plate. Engraving is an intaglio process, a term derived from an Italian word meaning an incised design. In the intaglio process the printing surface is sunk beneath the areas that are to remain blank. The lines are cut into the metal using a burin, and can be identified as engraved by the way they swell and taper to a point at the tip. The ink is applied to the plate with a dabber or roller, and forced into the grooves and pits. The surface of the plate is then wiped clean. To take an impression a sheet of paper is laid on the inked plate, and together they are submitted to sufficient pressure to drive the paper into the grooves so that it picks up the ink.

The copper plate depicts a family tree of the Counts of Salvarolo, a Venetian family. The central trunk shows the descent of the family from eldest son to eldest son down the main stem of the tree and brothers and cousins in the branches. Only the male line is shown. At the base of the tree is a two-headed eagle bearing the family arms, and either side of it the family's attributes - on the right a tree and various objects symbolising devotion and learning such as the hats and staffs of bishops and cardinals and books, mathematical and musical instruments. A medallion showing the winged lion of St Mark, the symbol of Venice, is depicted. The cannon, flags and drums point to the family's prowess in war. A palm tree, representative of victory, is depicted on the far left. This is probably the engraved plate for a family tree produced for the 'Memoria sopra la famiglia de' Signori Altani, conti de Salvarolo', published by Enrico Altan the Younger, Count of Salvarolo, in 1717.