Saint-Maur · 1734
Traité général des horloges
dom Jacques Alexandre · Paris, Hippolyte-Louis and Jacques Guérin · one volume, VIII and 387 pages, with folding plates
A Benedictine of Saint-Maur set out to describe every machine then used to divide the day: the shadow on a wall, water falling from cell to cell inside a drum, the weight-driven movement of a town tower, the spring in a pocket watch, and the engine that cut the wheels for all of them. The book appeared in 1734, the year its author died at Orléans. More than a quarter of it is a bibliography of everything written on clocks before him.
Nine chapters, from the gnomon to the pocket watch
The chapters run from the simplest instrument to the most delicate. Chapter I, on solar clocks, occupies pages 28 to 72: a practical course in laying out a horizontal dial, a vertical one, one declining eighty degrees under an elevation of forty-eight, and then in getting the drawing onto a wall, with the arcs of the signs and the arcs of the days at the end. Chapter II turns to water, and on page 74 credits one machine in particular — the hour drum that dom Charles Vailly, another Benedictine of Saint-Maur, had built at Sens in Burgundy in 1690 by a local étaminier named Regnard. Water inside a soldered drum passes from cell to cell through a hole the thickness of a needle; the drum, hung off its centre of gravity on two twisted cords, sinks under its own weight. Alexandre gives the partitions, the soldering, the movement of the drum and the marking of the hours a section each.
Chapter III, pages 88 to 141, treats clocks de gros volume, the weight-driven movements of church and town towers, and works down through the simple pendulum, the isochronous pendulum, quarter and hour striking, detents, bascules, remontoirs and the alarm. Chapter V gives fifty-two pages to the Sun, Moon and planets, taking them in turn from Mercury to Saturn and ending on planetary watches, because a clock that shows the heavens must first know them. Chapters VI and VII come back down in scale, to clocks of middling size and then to pocket watches; Chapter VIII, from page 254, to repetition work and to the engine that cuts the wheels.
Eight years from permission to press
The book was slow to reach the press. Dom Pierre Thibault, Superior General of the Congregation of Saint-Maur, licensed its printing at Orléans on 12 May 1726, his secretary Fr Joseph Castel countersigning. The royal censor’s approbation, signed Godin — the book does not say which Godin — is dated Paris, 16 February 1733, and is candid about why such a survey was wanted: the public had long wished for a complete treatise on horology, and in the meantime this one could be put in its place. The privilege of Louis XV followed on 2 May 1733, good for six consecutive years. A fortnight later Hippolyte-Louis Guérin, whose shop stood in the rue Saint-Jacques, made his brother Jacques a half-share of it, and on 16 May the cession was entered in the eighth register of the Chambre royale des libraires et imprimeurs de Paris, number 527, folio 515.
The volume appeared in 1734. Its author — born at Orléans on 24 January 1653, professed at the abbey of Vendôme on 26 August 1673 — died at Bonne-Nouvelle, in Orléans, on 23 June of that same year, sub-prior of that house, aged eighty-one; whether he saw the printed book we do not know. A letter from the chevalier de Louville, of the Académie des sciences, is printed among the preliminaries, praising above all the history of wheel clocks. Louville had been dead since September 1732.
The hundred pages at the end
Chapter IX is a bibliography of horology: titles, editions and, where Alexandre had the book in hand, an account of what was in it. It begins at page 277 and runs to the end of the text at page 387, in four articles — bare titles, authors and editions for the books on sundials; the same for sand and water clocks; then, for wheel clocks, extracts from every book he had managed to handle, with his own observations added; and from page 383 an index of the authors cited in the treatise. The book’s own table of chapters prints 275 for the start of the chapter, two pages before the heading actually falls. A leaf of Fautes à corriger follows page 387, before the table and the privilege.
How many plates the book ought to have is not settled. The Zurich copy is catalogued by the ETH-Bibliothek with twenty-six folding copper engravings; auction and dealers’ descriptions of the first edition give twenty-seven, and four folding letterpress tables besides. The format is disputed in the same way, called an octavo in one catalogue and a duodecimo of 12.5 by 19 centimetres in another. The plates examined — II, X and XXIV — are signed Dheulland sculp., without a first name. Most of what Alexandre wrote never reached print at all: his papers were said, a generation later, to be kept in a folio volume in the library at Bonne-Nouvelle, and we have not traced them since.
Why it is here
The ninth chapter is the part of this book that concerns the Conservatoire most. A man who could not read everything on his subject said so, listed what he had actually handled, marked his own observations as his own, and left the rest as bare titles. That is the standard the library and archive holds itself to, and the habit the courses are meant to pass on. The plates have a second use: they are working drawings of mechanisms before they are ornaments, and they belong nearer the workshops than a display case.
SourcesThe opening photograph shows a copy of the first edition open at two of its folding plates. The two plates reproduced here are from the copy digitised by the ETH-Bibliothek Zürich, shelfmark Rar 2052 (doi:10.3931/e-rara-14928), published on e-rara under a Public Domain Mark; the 1734 printing is itself in the public domain. The chapter and page references, the permission of 1726, the approbation of 1733 and the privilege are read from that copy, whose preliminaries and table of chapters may be turned page by page. The collation of twenty-six plates is the ETH-Bibliothek’s description of its own copy, not a statement about the edition.