Tractatus philosophicus de Barometro.

3 works in 1 vol., 8vo: [4]-188 pp.; 12 pl. (errata leaf missing, some soiling in the margins).

Contemp. vellum (old labels on front cover), ink titled flat spine (old labels).

Rare first edition, variant issue of this scholastic work by the Jesuit from Liège L. Gobart (1656-1750). Ill. with 12 engr. pl. showing barometers. In the first part Gobart explains the reasons why mercury in a barometer ascends and descends. In the second part he explains the conclusions to be drawn when mercury at a certain degree stops moving up or down. Other subjects he digs into are thermometers, the ebb and flow of the sea, etc.
Ref. STCN. - DBS III:1504-1505:2. - BnF. - Cp. Blake 178, COPAC.
Prov. Ownership entry on title crossed out. - Bibliotheca Hageveldensis (libr. stamp and label).
Bound with: 1. Le Lorrain de Vallemont, Pierre - Description de l'aimant, qui s'est formé à la pointe du Clocher neuf de N. Dame de Chartres. Paris, L. d'Houry, E. Couterot, 1692. [12]-215-[1 bl.] pp. (soiled, more obtrusive on lower corner last quires, min. paper flaw on p. 105, sm. (ink)stain on title). First edition of this important treatise on magnets and magnetic theory by the Jesuit and theologian Le Lorrain de Vallemont (1649-1721). Ill. with an engr. headpiece. Vallemont describes a violent thunderstorm in October 1690 - demolishing the steeple of N. Dame de Chartres - during which the phenomenon of magnetism clearly manifested itself through a piece of iron that belonged to the steeple of the church. Ph. de La Hire (1640-1718) already tried to give an explication of the phenomenon, but it was B. Franklin (1706-1790) who first discovered that electric fluid gives iron the properties of a magnet. Ref. Wheeler 205. - Caillet 10983. - BnF. - COPAC. - 2. [Gauger, Nicolas] - La mechanique du feu, ou l'Art d'en augmenter les effets, & d'en diminuer la dépense. Contenant le traité de nouvelles cheminées [...]. Amsterdam, D. Mortier, 1714. x-267-[9] pp.; 12 pl. (front. missing, soiling on upper margins and lower corners). Later Amsterdam edition, variant issue of this wonderful study of the mechanics of chimneys and fireplaces by the lawyer at the French court and royal book censor N. Gauger (ca. 1680-1730). Ill. with a vign. on title and 12 engr. fold. pl. Gauger aimed to improve the use of fires to ameliorate health, sanitation and domestic welfare. Title in red & black. Ref. STCN. - COPAC. - Cp. Poggendorff 1:852, BnF.