Dom Bédos de Celles
François Lamathe Bédos de Celles de Salelles, known as Dom Bédos de Celles, (24 January 1709 – 25 November 1779) was a Benedictine monk best known for being a master pipe organ builder.
He was born in Caux, Hérault, near Béziers, France. He was elected to the French Academy of Sciences at Bordeaux and correspondent of the Academy at Paris in 1758.
As a recognized organ-builder, he was called upon to carry out repairs and appraise and advise other organ-builders in many locations across France.
In 1760 he published "La Gnomonique pratique ou l’Art de tracer les cadrans solaires" under the patronage of the Jean-Paul Grandjean de Fouchy, Secretary of the Academy of Sciences and an authority in gnomonics and sundials.
In 1766-78 he published his treatise L'art du facteur d'orgues (The Art of the Organ-Builder). This monumental opus contains great historical detail about eighteenth-century organ building, and is still referred to by modern organ-builders.
He is buried in the former Abbey (now Basilica) of Saint-Denis.
The 26 images below are taken from this work, kept in the St.Bernard's abbey library in Bornem.
Title page
The Dom Francois Bedos de Celles method (1790) otherwise known as the Waugh method (1973), enables a dial to be constructed on a narrower piece of paper or velum, than using Dürers (1525) method- though it is essentially the same for the hourlines 9 to 3. It relies on a theorem proved on 1682 by P. de la Hire.
Setting out a dial for 52°N. The three initial lines.
Marking the latitude, laying out length , and copying to G on the vertical.
...
Wikipedia