Pulleys, cords and balances: how weight multiplies through tackle

A weight is felt through the whole cord; 4 pounds load the cord as 8

If 2 pounds are placed at f they are felt throughout the whole cord to a, as if it were straight; hanging 2 more at a resists f's descent. Holding a cord with 4 pounds tied to it, you cannot lift the weight unless you pull up more than it pulls down; so the cord suffers as much for the resistance as for the power of the weight, and a cord seeming to sustain 4 pounds sustains 8.

A bank of 29 pulleys: 100 resists 2900

Above and below a system of 29 pulleys operating on two rods pivoted like the arms of a compass: here a hundred of weight resists two thousand nine hundred of force, and the cord feels 100 pounds as many times as there are of its straight lines.

Chained rods geared 1:10 balance a pound against a hundred million

A system of seven rods, each in the ratio 1:10, mounts the values 1, 10, 100, 1000, 10000, 100000, a million, ten million; and, he notes, with 8 rods one pound stands equal to a hundred million.

The suspended weight loads the whole cord equally

The gravity suspended by the cord is wholly in the whole cord and wholly in every part of its length. Since both the power of the weight and its resistance are found in every part, if the weight is 4 the resistance is also 4, so the part and the whole of the cord feel 8.

Men on the sea floor bearing the whole ocean

If the whole bottom of the sea were covered with men lying down, those men would sustain the whole element of water, so that one man would have a mile-thickness of water upon him; for if the whole sea is sustained on its bottom, each part of the bottom sustains its part of the water.

A jack for hooping casks

Below the pulley diagrams, a device fitted with a pulley is labelled a jack ("cane") for putting hoops on casks.

Facciata destra. Metà destra, da destra a sinistra sira. Numeri:

Tre sistemi di carrucole coi numeri:

Quattro sistemi di carrucole con:

Sotto le precedenti, congegno con carrucola:

Parallelepipedo sospeso a due corde:

Margine destro:

Cinque sistemi di carrucole con:

Peso attraversato da una grossa corda:

Cinque sistemi di carrucole con:

Sistema di 7 aste collegate e bilanciate col rapporto 1 : 10 ciascuna:

Sopra e sotto a un sistema di 29 carrucole operanti su due aste imperniate come aste di compasso, con:

Prima colonna della metà sinistra. Figure di una corda semplice e una girata su carrucola, con:

Sistema di quattro carrucole, con:

Due sistemi di doppia carrucola con:

Più sotto:

Colonna lungo la piega mediana.

Figura di doppia carrucola con:

Continua dopo le due figure di carrucole:

Facciata sinistra. Prima colonna. Asta sospesa con:

Idem con:

Terza colonna. Asta composta con:

Quarta colonna. Asta composta con:

Sistema di 4 aste collegate e bilanciate col rapporto 1 : 10, con:

Quinta colonna. Asta sospesa a tre corde, con:

Asta sospesa a due corde, con:

Asta sospesa a tre corde, con:

Asta sospesa a cinque corde, con:

Asta sospesa a una corda:

Schema di bilancia coi pesi:

Asta sospesa a due corde:

Asta sospesa a una corda con:

Idem, con:

Asta con tre pesi applicati e due da applicare:

Doppia asta sospesa, con:

Sesta colonna. Sistema di aste sospese, con:

Schema di bilancia con pesi indeterminati:

Asta obliqua sospesa:

Sistema di aste sospese, con:

Schema di bilancia con tre contrappesi:

Schema di bilancia con:

Settima colonna. Tre corde con tre aste:

Doppia carrucola con:

Carrucola con:

Asta angolare con:

Bilancia con aste sospese:

Sistema di carrucole:

Right side. Right half, from right to left. Numbers:

Three pulley systems with the numbers:

Four pulley systems with:

Below the preceding, a device with a pulley:

Parallelepiped hung from two cords:

Right margin:

Five pulley systems with:

Weight crossed by a thick cord:

Five pulley systems with:

System of 7 connected rods each balanced at the ratio 1:10:

Above and below a system of 29 pulleys working on two rods pivoted like compass arms, with:

First column of the left half. Figures of a simple cord and one turned over a pulley, with:

System of four pulleys, with:

Two double-pulley systems with:

Further below:

Column along the median fold.

Figure of a double pulley with:

Continues after the two pulley figures:

Left side. First column. Suspended rod with:

The same with:

Third column. Compound rod with:

Fourth column. Compound rod with:

System of 4 connected rods balanced at the ratio 1:10, with:

Fifth column. Rod suspended by three cords, with:

Rod suspended by two cords, with:

Rod suspended by three cords, with:

Rod suspended by five cords, with:

Rod suspended by one cord:

Diagram of a balance with the weights:

Rod suspended by two cords:

Rod suspended by one cord with:

The same, with:

Rod with three weights applied and two to be applied:

Double suspended rod, with: