Crucibles, a geared millstone and a goose-foot oar

Crucible charged with live coals

One crucible drawn with glowing coals is labelled b and instructed: take coals without lumps. Its proportions are given as thick 1/4, wide and high 2/3. Neighbouring crucibles are packed with iron wire and with sponges.

Three-stage gear train of the millstone A

The central millstone is driven through three motions: the wheel of the first motion, A, has 180 teeth; the lantern-pinion and shield of the second motion are 8 and 64; and the lantern-pinion of the third motion, that of the millstone itself, has 8. The train makes the millstone turn 144 times for a single turn of the first wheel.

Boat rowed with a goose-foot oar

A man in a small boat pulls an oar annotated to work 'in the manner of a goose's foot', a feathering blade that opens on the pull and folds on the return to drive the craft through the water.

Gearing multiplications

Columns of figures work the gear ratios: 18 and 8 combined to 144, and 64 with 18 giving 512 and on to 1152, checking the 144-to-1 reduction of the millstone train.

In alto, da destra a sinistra. Elemento verticale puntellato, con:

Elemento quadrato, con:

Crogiuolo, con:

Uomo in barca con remo:

Crogiuolo colle dimensioni:

Altra figura di crogiuolo, con:

Crogiuolo con carboni accesi:

Margine opposto. Sezione di crogiuolo, con:

Al centro, macina, e particolare della stessa, con:

Operazioni aritmetiche:

At the top, from right to left. Vertical shored element, with:

Square element, with:

Crucible, with:

Man in a boat with an oar:

Crucible with dimensions:

Another figure of a crucible, with:

Crucible with lit coals:

Opposite margin. Section of a crucible, with:

At the centre, a millstone, and a detail of the same, with:

Arithmetical operations:

Crucibles, a geared millstone and a goose-foot oar

On this page

Crucible charged with live coals

Three-stage gear train of the millstone A

Boat rowed with a goose-foot oar

Gearing multiplications