Suspended-beam weights and a book memorandum
Numeric schemes for a balanced beam, with a note of the Gesuati and the Letters of Phalaris
Two small mounted fragments carry Leonardo's numeric schemes for the equilibrium of a suspended beam (asta sospesa), sketched as a horizontal balancing rod marked off with fractional weights. A brief upper note records 'the Gesuati' and the 'Letters of Phalaris', a memorandum naming a source or book. The large sheet mounted below is blank on this recto face, showing only the ink of its densely written verso bleeding through.
On this page
First scheme of a suspended beam
A horizontal rod is drawn balanced on a support and marked off in fractional divisions. Leonardo labels it the 'first scheme of a suspended beam' and sets the weights 12, 4 and 4 along a length of 1 1/3. The figures work out the load carried at the far extremity of the beam.
Fractional schemes of weights
Alongside the beam Leonardo lays out two further numeric schemes in fractions such as 1 1/2, 2, 2/3 and 2/6, with paired ratios like 6/1 and 1/6. They tabulate the proportional weights and lever-arms used in the beam calculations.
Note of the Gesuati and the Letters of Phalaris
A short note at the top of the left fragment reads 'the Gesuati' and 'Letters of Phalaris'. It is a memorandum naming a source or book, standing apart from the mechanical study on the sheet.