Two Volumes duodecimo contemporary marbled calf, 5 raised bands, spine compartments and titles gilt (tips and spine-edges rubbed & 4cm patch of leather missing from font cover of Vol I) marbled end-papers & armorial bookplates with eagle & sailing-ships, top corner of 1st EP torn off All Edges Marbled. Spoardic light spotting and traces of light marginal waterstain to first 30 pages, otherwise very clean & crisp throughout, [1]Half-title & Avis au Relieur +[2]1st titlepage & blank +xv (inc 2nd titlepage) +[1] +424 +[2]pp errata +12 folding copperplates, [4](inc Vol II titlepage) +501 +[3]pp +6 folding copperplates. *Sigaud de Lafond was a pupil of the Abbé Nollet who produced an earlier work with the same title. Splendid folding copper-plates in pristine condition all illustrating scientific experiments.