(1727 – 1817)
Lettres physiques et morales, sur les montagnes et sur l‘histoire de la terre et de l‘homme: adressées a la reine de la Grande Bretagne.

(Première partie). XVIII, 266 pp. The Hague, De Tune, 1778. – [And]: Lettres physiques et morales sur l‘histoire de la terre et de l‘homme… Tome I (- Tome V). viii, 1-224, ccxxv-ccclxviii, (225-268), (cclxix)-cclxxiv, (275)-430; [2], 539; [2], 566 (recte 567); [4], 640; [4], 772, [2] pp.The Hague, De Tune and Paris, Veuve Duchesne, 1779-1780.Together six volumes 8° (205×120 mm). Contemporary boards of blue paper, spine gilt with fillets, and orange labels for the title and oval-shaped volume numbers. Edges and corners somewhat scuffed. Toned and slightly foxed in places.
BIBLIOGRAPHY: Perret, 1269; Ward & Carozzi 631.
A rare complete set in first editions of the major geological work by the Swiss geologist, natural philosopher and meteorologist, Jean-André Deluc. The work consists of philosophical lettres mainly on his geological researches in the Swiss Alps, adressed to the queen consort of Great Britain, Charlotte of Mecklenburg-Strelitz (1744-1818).A first part under the title Lettres physiques et morales sur les montagnes was published in 1778 and relates in fourteen letters his voyage mainly to the Valley of Lauterbrunen and the Glacier of Grindelwald as well as Neuchâtel and the Jura from September 1774 to April 1775. On page VIII of the Preface, Deluc introduces the term “géologie” for the first time as a more appropriate word than “Cosmologie” for the knowledge or understanding of the earth and its structure. The following five volumes, with the title omitting sur les montagnes, were published independently, as Deluc points out explicitly in the ‚Avertissement‘ to the first volume. The last volume contains a report on an excursion to the Savoy Alps.”Deluc believed that the six days of the Creation were six epochs that preceded the present state of the globe, which began when cavities in the interior of the earth collapsed and lowered the sea level, thereby exposing the continents. There was thus a distinction between an older creative, or antediluvian, period and a newer, or diluvian, period” (DSB IV, 28). [369022].