1786 description of the historic Montgolfier Brothers’ 1783 balloon flight. Illustration with engineering proportions and description.
Translation: Figure and exact proportions of the “Aerostatic Globe”, which was the first to first carry men through the air.
Engineering data is provided in prerevolutionary French units:
Height of the Globe: 70 pieds
Weight of the Globe: 1600 Livres
Diameter: 46 pied
Lifting capacity: between 1600 and 1700 livres
Volume: 60000 pieds cubes
Gallery: 3 pieds wide
These units, while translating literally to “feet” and “pounds”, varied regionally and the version was not specified by the engraver. If Parisian units were used (by far the most likely) then this translates to metric and Imperial measurements as follows:
Height of the globe: 70 pieds du roi = 22.7 metres = about 75 ft
Weight of the globe: 1600 Livres = 780 kg = 1700 lb
Diameter: 46 pieds du roi = 14.9m = 49 ft
Lifting capacity: 1600-1700 livre = About 780-830 kg = about 1700-1800 lb.
Volume: 60000 pieds cubes = ~2000 cubic metres or 2,000,000 Litres = 73000 cubic ft.
Gallery: 3 pied du roi = 1 metre= 3 ft
Remainder of translation:
The top portion was surrounded by fleurs-de-lys, with the twelve zodiac signs below. In the middle portion were images of the king’s face, each surrounded by a sun. The bottom section was filled with mascarons and garlands; Several eagle’s wings appear to support this powerful machine in the air. All of this ornamentation was gold on a beautiful blue background, so that that this superb globe appeared to be gold and azure. The circular gallery, in which we see the Marquis D’Arlandes and Mr. Pilatre de Rozier, was covered in crimson draperies with gold fringes.