I. Versions and variants

Since the Paris manuscript BNF Fr. 12265 reveals many revision stages, it was crucial for the editors to make explicit the main stages of revision in structure and content made by Émilie Du Châtelet, through establishing them as textual versions on their own, rather than placing them in the variant apparatus. On the one hand, this makes it easier for the reader to perceive the differences by presenting the versions as distinct texts, so that the reader does not need to reconstruct all revision stages from the entries in the variant apparatus, which at times is quite a complicated task. On the other hand, in order to analyze the differences between the revision stages in detail, the reader needs to compare the online edited versions by arranging them in separate windows on the screen or display. This might be demanding at times, yet it is still easier than reconstructing all revision stages from the variant apparatus.

However, in order to make the comparison between the distinct versions easier, we decided to offer, in these introductory notes, a survey of some striking differences between the versions. We continue to provide a variant apparatus, however, representing the finer-grained revisions made by Émilie Du Châtelet.

By consequently establishing versions as texts on their own, and as distinguished by the amount of changes in structure and content, we also establish revision stages as variants which might only consist of one word being changed.

We have identified seven total revision stages in this chapter. There is an initial fair copy (siglum A), which then undergoes various revisions, leading to a final handwritten version (siglum F). In addition, there are the two published printed versions from 1740 and 1742 (sigla F and G). The final manuscript revision stage is available as a full version E, with the earlier revision stages available in the edition as variants

VERSIONS AND VARIANTS	SOURCE
A = VARIANT DOCUMENTED IN THE VARIANT APPARATUS OF VERSION E	Émilie Du Châtelet: Institutions de physique, Bibliothèque nationale de France, sign. Fr. 12265, 246r–253r
B = VARIANT DOCUMENTED IN THE VARIANT APPARATUS OF VERSION E	Émilie Du Châtelet: Institutions de physique, Bibliothèque nationale de France, MS fr. 12265, 246r–253r
C = VARIANT DOCUMENTED IN THE VARIANT APPARATUS OF VERSION E	Émilie Du Châtelet: Institutions de physique, Bibliothèque nationale de France, MS fr. 12265, 246r–253r
D = VARIANT DOCUMENTED IN THE VARIANT APPARATUS OF VERSION E	Émilie Du Châtelet: Institutions de physique, Bibliothèque nationale de France, MS fr. 12265, 246r–253r
E = MAIN TEXT = VERSION	Émilie Du Châtelet: Institutions de physique, Bibliothèque nationale de France, MS fr. 12265, 246r–253r
F = MAIN TEXT = VERSION	Institutions de physique, Paris: Prault, 1740, 273–287
G = VARIANT DOCUMENTED IN THE VARIANT APPARATUS OF VERSION F	Institutions physiques, Amsterdam: Au Depends de la Compagnie, 1742, pp. 285–300

II. Short survey of the main manuscript version E

As with the surrounding chapters, an initial fair copy (version A) is then significantly revised in Du Châtelet’s hand, with some passages being worked over in great detail across many versions. The fair copy appears to be in a hand that has not appeared previously in the manuscript. Thus the fair copy may be due to a different copyist than the fair copies of the earlier chapters.

III. Some significant differences between versions

A first important revision appears early in the chapter. Du Châtelet is discussing experimental evidence for Galileo’s law that (in the absence of resistance) all objects in free fall accelerate equally towards the earth. Galileo had merely conjectured about free fall in a vacuum. However, experiments were later made in a vacuum chamber to confirm this law. The first draft (version A) attributes these experiments to Newton and does not raise any problems with them. Later drafts delete the attribution to Newton, and note limitations with the vacuum chamber experiments, namely that bodies fall too quickly for their impact to be observed precisely. She then turns to a description, added only in later versions, of Newton’s famous double pendulum experiments.

Second, Du Châtelet importantly amends a discussion of experimental evidence for absolutely empty space. The same experiments in a vacuum chamber, she writes in the fair copy, “prouve invinciblement le vide absolu” (247r). First this is revised to “prouve invinciblement lexistence du vide,” thus omitting any reference to an absolute vacuum, and adds the qualification “sil y a cependantquelque chose qui puisse le prouver davantage que le vide meme” (247r). These revisions are of interest in context because the final, published versions omit these claims about empty space, and the published work elsewhere states that there is no void (vuide) in nature (§ 196).

Finally, an important note in Du Châtelet’s hand at 248v reads: “j’ay oté detout le paragraphe lenom demr. huguens.” This note appears to come from late in the revision process: it appears within a fair-copy discussion of Huygens’s Horologium Oscillatorium, which in fact does still name Huygens. Here, however, one can compare p. 280 of the 1740 printed version, where the three points formerly ascribed to Huygens as suppositions are now simply advanced as assumptions required as needed to generalize his reasoning.