Self-tipping excavator cart, with a draft letter
A wheeled dumping cart in red and black ink, columns of numbers, and a drafted complaint to 'Your Lordship'
The large drawing, laid out in red and black ink, is a wheeled 'excavator cart' whose body pivots so that its load tips out on its own once the front lifts, described with the reference letters to, dc, ba, c d, o t and a b. Around it Leonardo has drafted a letter to a 'Your Lordship', warning that a man who failed to extort promises from him is now scheming to turn his friends and benefactors against him, and closes with the salutation 'Most loving in Christ.' Columns of numbers accompany the text, and notes record turning the sheet by 90 degrees to write in the free margins. Dense further writing at the lower right is not transcribed here.
On this page
The self-tipping cart mechanism
The cart's body is designed to empty itself: when the load lies further to the rear beyond the pivot, that part sinks and c d comes to rest on o t while the front rises, leaving the body free on the wheels. When a b touch, c d no longer holds the bottom of the body down, and it lifts and tips its load out. Leonardo tracks the parts with the letters to, dc, ba, c d, o t and a b.
Draft of a letter to 'Your Lordship'
A drafted letter complains of a man who, cheated of promises he tried to extort, has attempted to take away all of Leonardo's friends and threatens to contrive some means of robbing him of his benefactors. Leonardo informs 'Your Lordship' so that the schemer may be foiled. It ends 'Most loving in Christ.'
A cart for moving and dumping earth
The vehicle is conceived as an earth-moving cart that carries a load and discharges it automatically when the front end lifts, sparing the labour of unloading by hand. Its self-tipping action is the point of the design.
Columns of numbers
Sets of figures are jotted among the text, given here as 20 22 16, 1 ... 9, 7, 5 2, and 2 ... 75. They sit apart from the letter and the cart description as separate reckonings.