Leonardo Da Vinci kept a to-do list. The thing that struck me was his interest in seeking out experts to teach him and show him how to do things. This list is from 1490 or so.
- [Calculate] the measurement of Milan and Suburbs
- [Find] a book that treats of Milan and its churches, which is to be had at the stationer’s on the way to Cordusio
- [Discover] the measurement of Corte Vecchio (the courtyard in the duke’s palace).
- [Discover] the measurement of the castello (the duke’s palace itself)
- Get the master of arithmetic to show you how to square a triangle.
- Get Messer Fazio (a professor of medicine and law in Pavia) to show you about proportion.
- Get the Brera Friar (at the Benedictine Monastery to Milan) to show you De Ponderibus (a medieval text on mechanics)
- [Talk to] Giannino, the Bombardier, re. the means by which the tower of Ferrara is walled without loopholes (no one really knows what Da Vinci meant by this)
- Ask Benedetto Potinari (A Florentine Merchant) by what means they go on ice in Flanders
- Draw Milan
- Ask Maestro Antonio how mortars are positioned on bastions by day or night.
- [Examine] the Crossbow of Mastro Giannetto
- Find a master of hydraulics and get him to tell you how to repair a lock, canal and mill in the Lombard manner
- [Ask about] the measurement of the sun promised me by Maestro Giovanni Francese
- Try to get Vitolone (the medieval author of a text on optics), which is in the Library at Pavia, which deals with the mathematic.