Translation:The Origins of Statics/Preface

The reader will not find in this work the order that had without doubt been desired there, that we had assuredly hoped to place there; he would be astonished to see our exposition return, repeatedly, on its steps, if he did not obtain from the first the explication of these singular traversings.

''Before undertaking the study of the origins of Statics, we had read the writings, little numerous, which treat the history of this science. It had been to us easy to recognize that they were, the majority of the times, good summaries and well little detailed; but we had not any reason to suppose that they would be not accurate, at least in the great outlines. In retaking therefore the study of the texts that they mentioned, we were anticipating that we would need to add or to modify well some details, but nothing allowed us to suspect that the whole itself of the history of Statics would be able to be overthrown by our researches.''

''These researches had led us, from first arrival, to some unforeseen observations; they had proved to us that the work of Leonardo da Vinci, so rich in new mechanical ideas, had not at all, as one commonly supposed it, remained unknown from the geometers of the Renaissance; that it had been exploited by many of the learned of the XVIth century, in particular by Cardan and by Benedetti; that it had furnished to Cardan his views so profound on the power motor of machines and on the impossibility of perpetual motion. But, from the time of Leonardo and of Cardan down to Descartes and Torricelli, we had been able to follow the development of Statics without the passage of this development having seemed to us essentially different from those that one would attribute commonly to it.''

We had commenced to retrace this development in the hospitable pages of the when the reading of Tartaglia, of whom no history of Statics even pronounces the name, came to us unexpectedly to show that the work, already primed, was needing to be begun again on an entirely new plan.

''Tartaglia, in effect, well before Stevin and Galileo, had determined the apparent weight of a body posed on an inclined plane; he had very correctly drawn this law from the principle of which Descartes was needing later to affirm the entire generality. But this fair discovery, of which no historian of Mechanics made mention, was not the deed of Tartaglia; it was, in his work, an impudent plagiarism; Ferrari reproached him harshly for it and claimed this invention for a geometer of the XIIIth century, for Jordanus Nemorarius.''

''Two treatises had been published in the XVIth century, as representing the Statics of Jordanus, but these two treatises were so different, they contradicted each other so precisely, that they could not be the work of a single author. If we were wanting to be familiar with exactly what Mechanics owed to Jordanus and his disciples, it was necessary for us to resort to the contemporaneous sources, to the manuscripts.''

Constrained we were therefore to despoil all the manuscripts relative to Statics that we had been able to discover at the Bibliothèque Nationale and at the Bibliothèque Mazarine''. This laborious despoilment, for which M. E. Bouvy, Librarian of the University of Bourdeaux, wished well to aid us with his very competent counsels, conducted us to a consequence absolutely unforeseen.''

''Not only had the western Middle Ages received, be it directly or be it by the intermediary of the Arabs, the tradition of certain Hellenic theories relative to the balance and to the lever of the Romans, but moreover its own intellectual activity had engendered an autonomous Statics, unsuspected by Antiquity. As early as the beginning of the XIIIth century, possibly even before this time, Jordanus de Nemore had demonstrated the law of the lever in setting out from this postulate: It requires the same power to elevate different weights, when the weights are in inverse ratio with the heights that they travel through.''

The idea of which the first germ was found in the treatise of Jordanus had grown, following a continuous development, through the writings of the disciples of Jordanus, of Leonardo da Vinci, of Cardan, of Roberval, of Descartes, of Wallis, to attain its form achieved in the letter of Jean Bernoulli to Varignon, in the Analytical Mechanics'' of Lagrange, in the work of Willard Gibbs. The Science of which we are today so legitimately proud derived, by an evolution which has been given to us to mark the gradual phases, from the Science which was born about the year 1200.''

''It is not at all solely by the doctrines of the School of Jordanus that the Mechanics of the Middle Ages has contributed to the formation of modern Mechanics. In the middle of the XIVth century, one of the doctors who was bringing the most honor to the brilliant nominalist School of the Sorbonne, Albert of Saxony, inaugurated a theory of the center of gravity which was obliging to have the greatest credit and the most durable influence. Impudently plagiarized in the XVth century and in the XVIth century by a crowd of geometers and physicists who reproduced it without naming the author, this theory flourished still in the heart of the XVIIth century; to he or she who ignores it, more than one scientific controversy ardently debated in this epoch remains incomprehensible. From this theory of Albert of Saxony has issued, by a filiation which has not at all suffered interruption, the principle of Statics enunciated by Torricelli.''

The study of the origins of Statics has conducted us thus to a conclusion; in proportion as we have pushed our historical researches earlier and in directions more varied, this conclusion has imposed itself to our spirit with an increasing force; also we dared to formulate it in its full generality: the mechanical and physical science of which we are well within our rights proud in modern times flows, by an uninterrupted series of scarcely sensible improvements, from the doctrines professed in the heart of the schools of the Middle Ages; the intellectual revolutions alleged have not been, most often, but slow and long-prepared evolutions; the self-proclaimed renaissances but reactions frequently unjust and sterile; the respect of tradition is an essential condition of scientific progress.

Les Origines de la statique/Préface