Raising a great tree upright without ropes
A method by which one man, with only a lever, fulcrums and wedges, raises a large timber on end
This sheet describes and diagrams a method for raising a great tree or timber upright using no ropes at all. Leonardo first lifts the middle of the trunk onto a support, then drives the head down into a hole so that the opposite end rises, and finishes with cones and wedges struck by blows; a companion figure shows how the middle of the timber is walked upward by lowering one end and packing wood beneath the foot step by step. He concludes that a single man can raise any great tree on end without a single rope, needing only a bar to serve as a lever. The figures carry the letters g p n, o m n, r, h g, b, n m and a.
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Raising a great timber on end without ropes
To raise a great tree upright, first lift its middle and give it a support at m. Then pull the head n down so that it enters the hole r, whereby the opposite head o rises; then with cones and wedges, by the force of the blow, raise it at ease, as shown at p for the beam h g. Finally remove m, dig under a, and with the blow from above at p a single man can raise any great tree upright with no rope — only a bar for a lever suffices.
Walking the middle of the timber upward
A way of raising the middle of the tree on high: when you lower the head at b, its foot a rises, and once raised you drive a piece of wood beneath it (under m); then do the like at n when the foot a has been drawn down again, proceeding step by step from beginning to end. The successive fulcrums exploit the lever repeatedly rather than lifting the whole load at once.