Raising a Column: Pulleys, Beams and the Friction of Loads
Cranes and scaffolds for lifting, with notes on weight, friction and pulling lines
The sheet swarms with pen sketches of lifting gear: sheer-legs, cranes, timber scaffolds, pulley blocks, a large toothed wheel and cylinders, all serving to raise heavy loads such as a column. The notes analyse how the weight of a leaning beam divides between two bearing points a and b and how friction between the loads must be reckoned. Further notes compare how hard it is to pull along different lines (b f, M b, f b, a b), citing propositions by number. Two lines of Latin at the top of the sheet are not part of the supplied transcription.
On this page
Weight and friction of a leaning beam at points a and b
At a lies the share of the weight given by the beam resting there, and at b the remaining weight of that beam. Anyone moving the load along these lines must reckon with the friction of the two weights a and b.
Pulling a framework of beams along different lines (a f b M)
Pulling along the line b f is difficult; but pulling along the line M b is the easiest of all, and along f b more difficult. Leonardo cites propositions by number and describes how a b raises and supports the whole load.
Knowing the middle of a motion from its beginning and end
From the beginnings and ends of motions one can know their middles. He then begins to argue about pulling along the line a b.