Pulley proportion, a covered cart, and geometric lattices
Red-chalk mechanics and geometry: weight-to-length proportion at a pulley, the top of a cart, and lattice figures
A working page in red chalk and pen. At the upper left a pulley (carrucola) is drawn with a short note stating that the proportion holding between the lengths r 4 and r 8 is the same as that between the weights 8 and 4, an inverse ratio of length to load. The centre carries a red-chalk sketch of the upper part of a cart or covered wagon, and the lower zone holds several small diamond-lattice figures labelled as geometric drawings, some written upside down with numbers. A few abbreviated Latin passive endings ('mur, ni, tur') survive at the top as continuation of the grammar drill.
On this page
Pulley: inverse proportion of length and weight
A pulley is drawn with lengths r 4 and r 8. The note states that the proportion which the length r 4 has to r 8, the weight 8 has to 4 - an inverse relation between arm length and load, the principle of mechanical advantage.
Upper part of a cart
A red-chalk sketch at the centre of the page shows the upper structure of a cart or covered wagon, captioned in the transcription as the 'upper part of the cart'. Only the tented top and part of the wheeled base are indicated.
Diamond-lattice geometric figures
Along the lower edge are several small figures built of crossed diagonals forming diamond grids, described as geometric drawings and drawn upside down. Loose numbers (4, 10, 483, 480) accompany them.
Fragment of the passive verb drill
At the top of the sheet a short line of abbreviated Latin passive endings (mur, ni, tur) repeats, continuing the conjugation exercise of the neighbouring pages.