80 PLrtTT's NATURAL HISTOET. [Book II. 



CHAP. 50. — TOENADOES ; BLASTING WINDS ; WHIELWINDS^ 

 AND OTHEE WONDEEFUL KINDS OF TEMPESTS. 



But if it burst from the cavity of a cloud which is more 

 depressed, but less capacious than what produces a squaU, 

 and is accompanied by noise, it is called a whirlwind, and 

 throws down everything which is near it. The same, when 

 it is more burning and rages with greater heat, is called a 

 blasting wind^, scorching and, at the same time, throwing 

 down everything with which it comes in contact. (49.) Ty- 

 phon never comes from the north, nor have we Ecnephias 

 when it snows, or when there is snow on the ground. K it 

 breaks the clouds, and, at the same time, catches fire or 

 burns, but not until it has left the cloud, it forms a thunder- 

 bolt. It differs from Prester as flame does from fire ; the 

 former is difiiised in a gust, the latter is condensed with a 

 violent impulse^. The whirlwind, when it rebounds, diflers 

 from the tornado in the same manner as a loud noise does 

 from a dash. 



The squall differs from both of them in its extent, the 

 clouds being more properly rent asimder than broken into 

 pieces. A black cloud is formed, resembling a great animal, 

 an appearance much dreaded by sailors. It is also called a 

 pillar, when the moisture is so condensed and rigid as to be 

 able to support itself. It is a cloud of the same kind, which, 

 when drawn into a tube, sucks up the water^. 



CHAP. 51. (50.) — OE THUNDEE^ ; IN WHAT COTJNTEIES IT 

 DOES NOT FALL, AND FOE WHAT EEASON. 



Thunder is rare both in winter and in summer^, but from 



^ The terms here employed are respectively " tm-bines," " presteres," 

 and " vortices." 



2 7rpr](TTr]p^ a TrpriOio, incendo. Seneca calls it "igneus turbo;" Nat, 

 Qusest. V. 13. p. 762. See also Lucretius, vi. 423. 3 Plutarch. 



* A water-spout. We have a description of this phaenomenon in Lu- 

 cretius, vi. 425 et seq. ^ " fulmen." 



^ This has been pointed out by Alexandre, Lemaire, i. 346, as one of 

 the statements made by our author, which, in consequence of his following 

 the Greek writers, apphes rather to their climate than to that of Italy. 

 The reader may form a judgement of the correctness of this remai'k by 

 comparing the account given by Aristotle and by Seneca ; the former in 

 Meteor, iii. 1. p. 573, 574, the latter in Nat. Qusest. ii. 32 et seq. 



