E12 -- De innumerabilibus curvis tautochronis in vacuo

(On the innumerable tautochrone curves in a vacuum)

Summary:

Publication:

Originally published in Commentarii academiae scientiarum Petropolitanae 4, 1735, pp. 49-67
Opera Omnia: Series 2, Volume 6, pp. 15 - 31
Reprinted in Comment. acad. sc. Petrop. 4, ed. nova, Bononiae 1743, pp. 42-57 + 2 diagrams [E12a]

Documents Available:

Original publication: E012 (in the Commentarii), Volume 4
Ian Bruce has made both a translation and transcription of E12 available at his page Mathematical Works of the 17th Century.