Fra Angelico to Leonardo: Italian Renaissance Drawings, British Museum

This superb exhibition of Italian Renaissance drawings, featuring 100 works and chosen from the outstanding graphic collections of the Uffizi and the British Museum, explores the evolution of the preparatory sketch in the 15th century. We learn how artists began to experiment with the medium in order to create finished paintings that were far more compositionally and stylistically ambitious, far more dramatic and full of movement, than anything that had come before. And though the drawings themselves were never meant to be seen outside the artist’s studio, we learn that by the early part of the 16th century, drawing had gained great importance as a medium in its own right.

Though certainly scholarly, this exhibition is far from dusty and dry: drawings have, after all, an immediacy and directness that comes with the form. In marks executed in graphite and chalk, or even in the precision-demanding metal point, we detect the pressure of the artist’s hand, his direct contact with the surface of paper, when, for instance, he softens a line by smudging it with his fingers. And preparatory drawings not only speak of the fluidity of the mark, but of the fluidity of ideas; we detect a palimpsest of underdrawings, of marks erased and remade, and of figures reconfigured. We note the artistic struggle for perfection.

There were many reasons underpinning this explosion in graphic mark-making, most obviously, the production of cheaply produced paper. Before paper’s ready availability, artists drew on vellum – stretched calf or goat skin – and this was often prohibitively expensive. The production of reasonably priced paper was crucial in liberating the artist from stiff, medieval imagery, for it freed him to continually experiment - with the numerous intricate folds of a piece of drapery, to explore different facial expressions for the same study, or work out dozens of different hand gestures, expending several sheets as he did so. It allowed him to experiment with ideas in concrete form.

And in turn there was a ferment of ideas that demanded such a commercial innovation. In the early 1400s we see the development of linear perspective (invented by Brunelleschi along strict mathematical lines and practised almost like a second religion by artists such as Uccello; we see the carefully measured grids and receding curves of a chalice drawn by him here). There was also an increased interest in grand classical forms, and with that a greater focus on naturalism. Inspired by classical sculpture, and drawn to the life around them, artists began to move away from copying iconographic images from model books.

Leonardo is well represented here. There are his early anatomical studies; a landscape, precisely dated 5 August 1473 (pictured right), which is thought to be the first landscape study in European art; military inventions - two tiny drawings of his famous but impractical war tank; quick, doodling sketches of a child and his wriggling cat. What’s more, a tender and softly delineated drawing depicting the downcast head of a women by Verrocchio, shows just where his most famous pupil got a few of his own tricks from.

Some 50 artists are represented in this impressively comprehensive exhibition. We move from comparatively static, but compelling illustrations by Pisanello (Studies of hanged men; and a woman and child; 1434-8; pictured left), to the dramatic gestures of Michelangelo’s male nudes some six decades later. It culminates with the High Renaissance genius of Raphael and Titian, the latter the undisputed Venetian master of Renaissance sensuality who is represented here by the unforgettable Portrait of a Young Woman, c 1510-1515 (main picture). We see only this young woman's head and shoulders, but in the fullness of her lips, the tumble of her hair on a bare shoulder, the plumpness of her flesh and those ever so slightly flared nostrils, nothing beats it for buttoned-up eroticism.

• Fra Angelico to Leonardo: Italian Renaissance Drawings is at the British Museum until 25 July