I have previously compiled brief biographic surveys of the authors of two of the earliest and best know machine books: Jacques Besson and Agostino Ramelli. I am now taking this opportunity to give the same service to Jacob Leupold whose 10-volume Theatrum Machinarum (1724-) marked the definitive end of the machine book's 150 year reign.
Leupold freely borrowed from the work of other scientists and authors in the compilations of his own volumes. More importantly, he was the first first of the authors to apply what we would now recognize as engineering rigour to the machines he was articulating. Reuleaux credited Leupold with being the first to consider elements separate from machines (despite Branca's poorly rendered depictions of machines disengaged from their power sources). Similarly, James Watt was a great fan of Leupold and went so far as to learn German in order to read the works (Ferguson, 1971). Even Wittgenstein owned five volumes--purchased from "Max Harrwitz, Potsdamer Str. 113, Berlin W., Buchhandlung und Antiquariat" for "K.180" (Hide, 2004).
A number of authors, most notably Ferguson, have called for an English translation of Leupold's work. None were forthcoming. Luckily, Wilfred George Lockett, a retired engineer, penned a most remarkable dissertation on Leupold in 1994. He managed to collect reproductions of all 10 of Leupold's works and a great deal of secondary literature, most of it non-English. Most remarkably, he obtained a reproduction of an unpublished English translation of the works. This manuscript is held by the Huntington Library and was likely commissioned by Charles Hamilton (1691-1754).
- July 25, 1674. Leupold is born in Planitz, near Zwickau in the Electorate of Saxony. He is the son of George Leupold: cabinet-maker, turner, sculptor, and watchmaker. Leupold recieved relatively little formal education but studied sufficient math at the area's four universities to become a tutor. For these lessons, he began to build mathematical instruments.
- 1698. He is apprenticed to an instrument maker. After six months, he left to open his own shop.
- 1701. Accepted post as the hospital warden. Leupold remained active in his instrument shop and persued his own technical instruments.
- 1704. Leupold become sick from an unknown illness, possibly a stroke which affected his memory and hearing. In his discussions on the capacity of humans for labour, he notes that he was able to lift and move far more weight before his illness.
- 1714. He resigned from the hospital and managed his instrument shop with several assistants. The shop produced both musical and scientific instruments. During this time, he is associated with University of Leipzig as "Mechanic."
- April 12, 1715. He is appointed member of Berlin Academy of Sciences. This positioned quickly attracts two other plum appointments: Commissioner of Mines to Saxony and Counsellor of Commerce to Prussia.
- 1724. The first volume of his TM appeared.
- January 12, 1727. Eighth volume of the TM is nearing completion when Leupold becomes suddely ill and dies. His obituary indicates that we was married twice but makes no mention of off-spring. However, the dedication of vol. 8 notes the deserving cause of "widows and orphans" indicating that Leupold may have had children.
Ten volumes of the theatrum machinarum were published, three of them posthumously:
- TM Generale (1724)
- TM Hydrotechnicarum (1724)
- TM Hyraulicarum Tomus 1 (1724)
- --- Tomus II (1725)
- Theatrum Machinarum (Heb-Zeuge; 1725)
- Theatrum Staticum Universale Part I T. Staticum
- --- II T. Hydrostaticum
- --- III T. Aerostaticum
- --- IV T. Horizontostaticum (all 1726)
- Theatrum Pontificiale (1726)
- Theatrum Arithmetico Geometricum (1727)
- Theatrum Machinarum Molarium (1735)
- Theatrum Machinarum Supplementum (1739)
While the expression "theatrum machinarum" had existed since the Berould editions of Besson's work, Leupold provides some explanation of the term. In the preface of vol.1, he notes:
"We will call this first section, as we intend to call all the subsequent sections, a Theatrum: as in it we show and display visibly, an in a theatre or on an open stage, the principles of Mechanics, and the various machines and devices by which these principles are illustrated." (Lockett 1994 pg. 14)
Leupold's intended audience was not highly educate elites but rather the common "mechanic." His work is addressed "...not to the learned and experienced mathematicians [Mathematicus] who are already, or should be, better acquainted with them... [and most of whom] have studied mechanics more as a subject of curiosity and a hobby, than with any view of service to the public. The people we had in mind were rather the mechanic, handicraftsman [Ku:nstler, Handwercker] and the like, who, without education or knowledge of foreign languages have no access to many sources of information..." (Lockett, 1994 pg. 16)
He also provides a working description of the practice of mechanics:
"The Practice of mechanics is the art of actually producing a machine based on mechanical theory and principles, so that it works properly.
1) Thus, briefly, a Theorist in mechanics is one who only understands the principles; while a Practitioner is one who knows how to design and produce a machine based on these principles.
2) An Empiricist in mechanics is one who can indeed construct a machine by traditional methods, as in the case of most of our master-craftsmen, carpenters, foremen, millers and the like; but who knows no reason or has no grounds as to why it should be such and such and not otherwise." (Lockett, 1994 pg. 32)
Leupold clearly acts on these sentiments. He tries to draw together mechanical theory with emerging scientific discourse. For example, he criticizes one of Ramelli's hauling machines for being over-complicated and over-geared. Unlike Ramelli, Leupold recognizes issues such as required human effort and--notably--friction. He takes Admontons's 1699 articulation of friction in machines and applies to an extant corpus of mechanical devices.
He also misses. For example, his work on bridges is woefully inadequate from the perspective on analysis (although he appears to have a better sense of statics that earlier authors such as Jean Errard Bar-le-Duc or Ambroise Bachot). Surprisingly, Leupold appears to be ignorant of some of the basic tenants of strength-of-materials as articulated by Galileo. I would have assumed that the technical writing of such a famous heretic would have been required reading in Saxony!
[Note: I'm currently only on page 77 of the dissertation... and since I'm waiting for Claire to go into labour I find myself oddly distracted from this sort of academic ritual. However, there are some other interesting dissertations out there including work on Salomon de Caus (also available at the Library of Canada Archives site), Renaissance iconography, Peter Ramus and English rhetoric, Domenico Fontana.]
Ferguson, E.S. (1971). Leupold's 'Theatrum Machinarum': A Need and an Opportunity. Technology and Culture. 12(1): 64-68.
Hide, O. (2004). Wittgenstein's books at the Bertrand Russell Archives and the influence of scientific literature on Wittgenstein's early philosophy. Philosophical Investigations. 27.1: 69-91.
Lockett, W.G. (1994). Jacob Leupold as Hyraulic Engineer: A Study of His Theatrum Machinarum. Unpublished PhD Dissertation, University of Toronto.