A tripod made from wood poles, with a rope and pulley attached, helps you lift weights higher or heavier than you could otherwise. If you hitch the rope to a vehicle, windlass, draft animal or anything that can pull on it horizontally, the tripod and pulley will transfer the horizontal force to a vertical one, so you can use it to lift a heavy object straight up. Use materials that are strong enough to withstand the forces involved depending on the weight you're lifting and make sure everyone is clear in case of accident.
Cut three poles 15 feet long using a handsaw, axe or chainsaw. Choose straight trees of a strong wood such as hickory, oak or ironwood and trim off any branches with a hatchet or chainsaw. Avoid poles with knots or weak spots.
Lay the three poles side by side on the ground and lash them together about 1 foot from the top ends using heavy rope or chain. Set them up and spread the bottoms to form a stable tripod over the object you want to lift. Test the tripod for sturdiness, then lay the poles down again or set up a stepladder so you can reach the lashed area.
Tie a rope or hook a chain around the lashed area and hang or tie a pulley beneath the lashed area. Run a rope over the top of the pulley's wheel so one end is long enough to reach the object you want to lift and the other end is long enough to pull on. Set the tripod up again if necessary or move the ladder.
Attach one end of the rope to the object you want to lift and take hold of the other end of the rope while you're standing on the ground beside the tripod. To raise the object, pull on the rope.
Wear gloves and a hardhat or other protective gear. Keep everyone clear and be ready to move out of the way quickly in case of equipment failure.