Other examples show the different uses to which drawings were put. There is a fine but macabre sheet by Pisanello (c. 1434-8) covered with six images of men hanging from a gibbet. It was a preparatory work for a background incident in his fresco of St George and the Princess of Silene in Verona and depicts the corpses in various states of decay as he worked out which poses were most suitable for the final work. Some of the sketches are clearly drawn from a posing model while two show a putrefying figure with a gaping mouth, vacant eye sockets and a neck snapped at a 90º angle that must have been drawn from life — or rather death. Despite the grisly subject matter, the bodies are drawn with great detail and almost loving delicacy.

Some drawings, such as Piero Pollaiuolo's head of the figure of Faith, show the holes that were pricked through the paper in order to transfer the exact design on to panel for painting. Some, such as Boltraffio's exquisitely rendered swirl of drapery on a roughly sketched figure of Christ, show the degree of care that underlay every element of a major commission in oil. Others, such as the sinuous, frothy figure studies by Parri Spinelli (1387-1453), show artists who were better draughtsmen than painters. 

There is a small clutch too of presentation drawings, autonomous works given to patrons or acquaintances as demonstrations of the artist's abilities or their friendship. The pick of them is Leonardo's celebrated profile Bust of a Warrior (c. 1475-80) showing a crumple-faced soldier in fantastical armour. It is a work of equal imagination and skill, drawn in metalpoint, a medium that, because it worked through a chemical reaction between the metal stylus and the prepared paper, allowed for no corrections or rubbings out. It is, in the very best sense, a show-off piece. 

The Leonardo, like many of the works in this thrilling selection, does what we have come to expect from the best drawings: they draw a direct line from the conception in the artist's brain, through his arm to their appearance on paper and, in doing so, take the viewer close to what in the post-Romantic age we presume to be the wellspring of creation.