Water as the vital humour of the earthly machine
An aphorism on water in red chalk, a building plan with a hearth, and a syllable-list
At the head of the leaf, in red chalk, Leonardo writes the microcosm aphorism that water is the vital humour of the earthly machine and moves through its natural heat. Beneath it is a small red-chalk plan of a building marked with its hearth (focolare), together with faint further sketches. In brown ink toward the lower left, and written inverted, is a short exercise of rhyming word-endings. Additional untranscribed jottings and faint drawings remain on the sheet.
On this page
Water moves by its own natural heat
Water is called the vital humour of the earthly machine, and it is by means of its own natural heat that it is set in motion. The statement frames the circulation of water in the body of the earth as a living process.
The earth as a living machine
By calling the earth a machine possessed of a vital humour, the note applies the microcosm analogy: water stands to the body of the earth as blood or humour stands to a living body.
Plan of a building with its hearth
A small red-chalk ground plan shows a rectangular building whose central feature is labelled focolare, the hearth or fireplace.
List of rhyming word-endings
Written inverted in pen at the lower left is a column of syllable-like words with matching endings: bare, bere, rere, mere. It reads as a spelling or rhyme exercise rather than continuous prose.