Forster Codices (I–III)
Leonardo's Pocket Notebooks — V&A Museum, London
Overview
The Forster Codices are three small pocket-sized notebooks by Leonardo da Vinci, bequeathed to the Victoria & Albert Museum in 1876 by the biographer and collector John Forster. Their miniature format confirms they were Leonardo's constant portable companions, slipped into his belt purse as he walked through Milan, Florence, and royal construction sites.
Forster Codex I (c. 1487–1505)
Bound in two distinct sections: the first part (commenced at Milan in July 1505) is Leonardo's dedicated treatise on stereometry — the mathematical transformation of solid geometric bodies without loss of volume, created in dialogue with Luca Pacioli. The second part (c. 1487–1490) records investigations in hydraulic engineering, Archimedean water screws, and studio varnishes.
Forster Codex II (c. 1495–1497)
Composed of two pocket notebooks bound together. Contains Leonardo's seminal physical theories on the resistance of timber beams, levers, and gravity. Most famously, folios 1v–2r contain Leonardo's only surviving direct written studies for the apostles of The Last Supper, recording the exact psychological gestures, hands, and facial expressions executed on the refectory wall of Santa Maria delle Grazie.
Forster Codex III (c. 1490–1493)
A densely packed notebook from Leonardo's prime years at the Milanese court of Ludovico il Moro. It contains his on-site foundry recipes for casting the colossal 70-ton Sforza Equestrian Monument (Il Cavallo) in bronze, workshop recipes for preparing silverpoint paper, purifying linseed oil, and allegorical fables such as the emblem of the pruned tree ("Ancora spero").
Key Subjects & Highlights
- The Last Supper Apostles: Direct psychological and gestural choreography (Forster II, f. 1v–2r)
- Foundry & Metallurgy: Sectional moulds and refractory clay for casting the Sforza Horse (Forster III, f. 50a–56a)
- Workshop Recipes: Oil varnishes, silverpoint paper grounds, and oil purification (Forster I & III)
- Stereometry: Archimedean volume conservation and solid geometry (Forster I, f. 1r)
- Biomechanics: Kinetics of the human body in running and dynamic balance (Forster II, f. 14a)
- Structural Engineering: Bending resistance and beam flexion (Forster II, f. 72b)