Stubble, Corn, or Hay in the Meadows are raised, and spread around in the Form of an +extended canopy+, (_inverted Cone_, _elliptic Solid_, and _hyperbolic Curve_.) See “Bacon’s Historia Ventorum”, Pag. 43, ad Articulum 10.[58] 236. If then it be allowed to reason from that Analogy which took Place in most of the Cases already mentioned; the _gentler_ Depression. of Balloons over Water in _milder_ Weather, may be owing to a Cause somewhat similar, tho’ not so evidently an immediate Object of the Senses, viz. _an actual tho’ invisible Descent of Air upon the Water_. 237. Blanchard in his Passage over the Sea from Dover to Bologne in France, when near the Middle of the Channel, suffered an unexpected Depression, and at the same Time was nearly +becalmed+. A +calm+ also took Place on the Irish Sea: which must have prevented Crosbie from landing,—without _Wings_, or some _propulsive_ Machinery, connected with the Balloon. 238. Lunardi rose from Liverpool when the Wind blew _boisterously_: yet was _becalmed_ twenty Minutes over the _broad_ Turn of the Mersey near Ince, when above the Level of the Wind: and, descending into the same Stream of Wind, was hurried along towards Beeston-Castle in Cheshire. CHAPTER XXXXIV. [Sidenote: Depressing Columns of Air known to the Egyptians.] Section 239. The Existence of depressing Columns of Air was well known to a People more ancient than either Romans or Greeks. 240. The sultry Climate of Egypt, whose Situation is that of an extensive Meadow watered by a _broad_ River, and enclosed by Mountains to the East and West; consequently not subject to general horizontal Currents of Air, except along the Line of its Meridian,—is _the Country_, wherein Columns of +cool+ Air descending on the Water, woud be soon observed. And they, in Fact, were almost the only People who applied the Observation to common Life: having, according to Herodotus, as well as later Writers, built lofty Structures +open at the top+. By which Means the cool Air +rushing+ downwards greatly refreshed the Inhabitants. The ancient Pantheon, at present called All Saints Church, now standing at Rome; built in the lowest Situation of a Street named the Piazza di Navona is on this Construction: and the Hint probably taken from an Egyptian Model. 241. In all inland Countries, whose Lakes are frequently surrounded by Mountains, as Bala-Pool in North-Wales; those of Westmoreland and Cumberland; the Lake of Geneva in Swisserland;—the Air rushes +forcibly+ on the Surface of the Water in descending Torrents: this the Writer has frequently observed.[59] (In other Languages, the Words applicable to Wind on a Lake, or the Ocean, signify Descent: as, Καταβαινω, and Επικειμαι· also the Northerly or _descending_ Wind corresponded to the Εκνὲφιας while the Southerly or _ascending_ Wind answered to the Απογη.)