but by the effeft of looming, it fometimes fubfides almoft totally in the horizon;
fometimes it rifes more acute and more elevated; fometimes it is hemifpherical ;
and fometimes its fides are perpendicular, its top flat, and as broad as its bafe. In fhort it affumes at times the moft whimfi- cal fhapes, and all thefe perhaps fucceffively in the fame morning. The blue ridge of mountains comes into view, in the north- eafl:, at about loo miles diftance, and approaching in a direft line, paffes by within 20 miles, and goes off to the fouth- weft. This phaenomenon begins to fliew itfelf on thefe mountains, at about 50 miles diflance, and continues beyond that as far as they are feen. I remark no par- ticular ftate, either in the weight, moif- ture, or heat of the atmofphere, necefla- ry to produce this. The only conftant circumftances are its appearance in the morning only, and on objects at leafl; 40 or 50 miles diftant. In this later circum- ftance, if not in both, it differs from the looming on the water. Refradlion will [ i6o ] not account for the metamorphofis. That only changes the proportions of length and breadth, bafe and altitude, preferving the general outlines. Thus it may make a circle appear elliptical, raife or deprefs a cone, but by none of its laws, as yet developed, will it make a circle appear a fquare, or a cone a fphere.