De Beghinselen der Weeghconst (lit. "The Principles of the Art of Weighing") is a book about statics written by the Flemish physicist Simon Stevin in Dutch. It was published in 1586 in a single volume with De Weeghdaet (lit. "The Act of Weighing"), De Beghinselen des Waterwichts ("The Principles of Hydrostatics") and an Anhang (an appendix).^[1] In 1605, there was another edition.

The importance of the book was summarized by the Encyclopædia Britannica:^[2]

In De Beghinselen der Weeghconst (1586; “Statics and Hydrostatics”) Stevin published the theorem of the triangle of forces. The knowledge of this triangle of forces, equivalent to the parallelogram diagram of forces, gave a new impetus to the study of statics, which had previously been founded on the theory of the lever. He also discovered that the downward pressure of a liquid is independent of the shape of its vessel and depends only on its height and base.

The first part consists of two books, together account for 95 pages, here divided into 10 pieces.

Start: panegyrics, Mission to Rudolf II, Uytspraeck Vande Weerdicheyt of Duytsche Tael, Cortbegryp Bepalinghen and Begheerten (definitions and assumptions)

Proposal 1 t / m 4: hefboomwet

Proposal 5 t / m 12: a balance with weights pilaer^{[check spelling]}

Proposition 13 t / m 18: follow-up, with hefwicht, two supports

Proposition 19: balance on an inclined plane, with cloot Crans

Proposal 20 t / m 28: pilaer with scheefwichten, hanging, body

Proposal 1 t / m 6: center of gravity boards – triangle, rectilinear flat

Proposal 7 t / m 13: trapezium, divide, cut fire

Proposition 14 t / m 24: center of gravity of bodies – pillar, pyramid, burner

The Weeghdaet

The Beghinselen des Waterwichts

Anhang

Byvough

• Simon Stevin

• Stevin, Simon (1955). Dijksterhuis, E.J (ed.). The principal works of Simon Stevin, Mechanics, edition Vol. I, volume (PDF) (in English and Dutch). C.V. Swets and Zeitlinger.