CHAPTER LXVI.
ON THE UTILITY OF BALLOONS.
Section 333. THE Balloon opens a new and unlimited Field for Philosophical Discoveries.
334. The many curious and interesting Conjectures which Mons. de Luc (before the Invention of Balloons) throws out, in the Course of 4 large Volumes, on the Subject and Qualities of the Atmosphere; may now be determined by actual Trial.
335. The Abbée Bertholon wrote in 1784: and has particularly mentioned the following Points, as capable of ample Investigation, and. Discussion.
Sect. 336. Art. 1. The Temperature of the Air at different Heights.
Which will determine whether the Atmosphere be practically Navigable, at all Times and Places.
336. 2. The dissolvent Power of the Air by Means of an Atmometer for Evaporation.
Probably the Height may be determined, to which Clouds commonly ascend in order to find the proper horizontal Level, in which Balloons can move with the greatest Ease, Safety, and Expedition.