Furnace, riverbank palisade, and a water-and-air bellows
A furnace heated top and bottom, a palisade to repair scoured banks, and a leatherless bellows, with a note on proportion
The sheet gathers several engineering notes. At the top a small furnace is designed to heat its base both from below and above; alongside, a palisade driven into a riverbed shows how an eddy scours the bank and how to rebuild it by nailing boards and planting alders that will knit into a living wall. A long note describes a bellows shaped like a sugar loaf, divided lengthwise into a water half and an air half so that falling water drives the air out. A closing paragraph 'On proportion' proposes throwing stones of different sizes to test whether the heaviest travels farthest, and whether equal pellets thrown together cover the same distance.
On this page
Furnace heated from below and above
A small furnace or oven is arranged so that its base receives heat both from beneath and from over it. The drawing at the top right shows the low boxed hearth.
Eddy scouring a riverbank at a m
The bed is to be filled at points a m below the bank; otherwise the eddy (ritroso) will hollow out and carry away the bank. The pile structure over swirling water at the upper left illustrates the scouring.
Palisade and a living wall of alders
To repair a ruined riverbank, first drive a palisade, then nail boards to it from outside, then set trees or alders inside about a span apart in every direction. After four years they knit together and form a wall.
Water-and-air bellows like a sugar loaf
The bellows is shaped like a sugar loaf, divided lengthwise by a partition into an upper part full of water and a lower part full of air. Water falls into the air vessel through a vent near the pipe, and its rising drives the air out of the mouth; a valve refills the water. It is called the most useful bellows one can use.
On proportion: distance of thrown stones
A test of whether the heaviest of many small stones of various sizes travels farthest when thrown alone by the same instrument and force, and whether it goes farther alone or accompanied. It also asks whether equal pellets, like blowpipe shot, thrown by one power at once cover the same distance.