472 METEOROLOGY. 



Professor Espy collected a iiumlier of cases in Pennsylvania and other parts 

 of the eastern States, of examples of this remark '>.ble phenomenon. The only 

 explanation winch appears to be sufKcient to account for it, and particularly the 

 amount of water which falls, is that of a water-spout or rotatory motion of the 

 air, produced by the disturbance of the ordinary stable condition of the atmo- 

 sphere by the abnomial heating; of the stratnm next the earth, and the subse- 

 quent bursting- of this upward, in the form of an ascending vortex, carrying with 

 it all the vapor which the air may contain from a smTounding- space of several 

 miles. 



The quantity of water which falls will depend upon the amount of vapor in 

 the atmosphere which has been drawn into the vortex. It should be recollected 

 that although the air may be ver^^ dry at a higli temperature, yet it may con- 

 tain a much greater quantity of water in the form of vapor than a damper 

 atmosphere at a lower temperature. Thus, at 70° of temperature the air, when 

 perfectly saturated, contains about eight grains of vapor to the cubic foot ; at 

 90° it is capable of containing about 15 grains. From this it appears that the 

 capacity for vapor increases very rapidly with the temperature ; in the case 

 above cited an increase of 20° of temperature nearly doubles the capacity for 

 inoistm'e, and consequently produces a character of extreme dryness. 



Although, at the same time, the air may contain a very large amount of vapor 

 •which, condensed by a diminution of temperature due to its increased elevation, 

 or perhaps by a colder stratum immediately above, may be precipitated on a 

 single spot, and thus give rise to the extraordinary effects above described. 



ACCOUNT OF A METEORITE. 



By Abner Woodworth, Council Grove, Kansas, March, 186G. 



On the 7th of March, 1843, 1 left Paral, a town situated on the river Allendo 

 Mexico, State of Chihuahua, and, travelling some 25 miles, course 1C° east of 

 south, passed a lump of solid malleable iron, shape or figure resembling- two 

 inverted saucers, one-third or more bm'ied in the ground, supposed to weigh 

 five or six thousand jiounds. It is softer than bar iron. The blacksmith at 

 Rio riorido cuts oil" pieces with his cold chisel for horseshoes. It lies upon a 

 level plain, 20 miles from any mountain. 



ACCOUNT OF A METEOKITE. 



BV EOBERT SiMSON. 



Shortly before an'iving at El Valle, on the road from Ilio Florido, we encoun- 

 ter first streaks of iron — grateful to the lips and hands, cracked and sore with 

 the lime through which we have for some time been travelling, (going north- 

 ward.) The hill-sides, where bare, now show a reddish color; and vegetation 

 is not so luxuriant as heretofore. 



About half-way between El Valle and Paixal, on a bend of the Rio Florido, 

 at a place called Concepcion, is a most splendid specimen of meteoric iron. It 

 is four feet above ground, and almost pure in quality. It is from two to three 

 feet one way, by, probably, two to five feet the other, very regular in shape, 

 and, where worn by the rubbing of hands, &c., of passers b}^, is bright, and, to 

 all appearance, is nearly pure metal. The steel hatchet cuts into it easily, but 

 with our means at hand wo found it impossible to detach any part of it. It 

 stood at the corner of the house, apparently to guai'd it from collisions of wagons 



