Traitez de l'equilibre des liqueurs, et de la pesanteur de la masse de l'air by PASCAL, Blaise - 1663

Paris: Guillaume Despree, 1663. 1st Edition. Hardcover. Very Good. 1st Edition. Hardcover. 12mo (148 x 84 mm). [28], 232, [8] pp. 4 folding engraved plates and 1 woodcut illustration on p.105. Early 18th century mottled calf, spine with lettering piece and 5 raised bands richly gilt in compartments, red sprinkled edges, original endpapers (corners scuffed, wear to extremities, joints and spine-ends repaired). Text and plates bright and clean with just very little age-toning, pale waterstain to margin of few pages, two words added within text in sepia in old hand, one pencil notation in the margin next to woodcut. The engravings are normally found as 2 plates; in this case, at time of binding, the plates were divided into 4 sections without loss of images, and placed presumably to correspond to the text. Provenance: old owner's ink signature on title page. In all a fine copy. ---- Dibner Heralds of Science 143; Sparrow Milestones of Science 157; Tchemerzine V, p. 59; Waller 12161; Norman 1650. - FIRST EDITION OF THE FIRST ACCOUNT OF PASCAL'S LAW, stating that pressure in a liquid is transmitted undiminished in all directions. Divided into two closely related parts, this posthumous work is devoted to the laws of hydrostatics and to the demonstration and description of the various effects of the weight of air. Continuing the investigations of Stevin, Galileo, Torricelli, and Mersenne, he provided in the Traites a lucid account of the fundamental concept of pressure. 'Using the recently invented Torricellian barometer, Pascal had his brother-in-law climb the Puy de Dome in 1648 and watch the barometer level fall with the ascent, thereby demonstrating that air had weight ... The relationship of barometric change and change in the weather was first outlined here' (Dibner).