ZJO Examination of Si. Pierre's HypotheJiS- 



a-day, by means of the counter-currents, which have abvayi 

 a velocity proportional to that of the principal current. 



The particular effects obferved in lakes and rivers commu- 

 nicating with icy mountains, illuftrate the nature of the polar: 

 effufions. A kind of flux and reflux in the lake of Geneva, 

 during liimmer and towards the evening, is obfervable, occa- 

 fioued by the melting of the mows, which fall into it after 

 noon in greater quantities than at other feafons of the day. 

 The intermittence of certain fountains is afcribableto the fame 

 caufe. The frequent and rapid fluxes (ten or twelve times 

 a day) of the Euripus, the {trait feparating Bceotia from Eu-* 

 bcea, arifc from the fame fource. 



The current? of the ocean are reducible to two general 

 ones: one, during our fummer, from the north pole, in a 

 fouth direction J the other, during our winter, proceeding 

 northward from the fouth pole. 



Dampier lavs it down as a principle, founded on many ex- 

 periments, that currents are fcarcely ever felt but out at lea, 

 and tides' upon the coafts. 



The polar effufions, which are the tides of the north and 

 eaft to thofe who dwell in the vicinity of the pole, or in bays 

 communicating with it, take their general courfe to the middle 

 of the channel of the Atlantic ocean, attracted toward the 

 line by the diminution of the waters, which the fun is inccf- 

 fantly evaporating. They produce by their general current 

 two contrary currents or collateral whirlpools iiinilar to thofe 

 produced by rivers on their banks, and the tides may be-con- 

 iidered as vortices of the general current of the Atlantic 



ocean- 



The general current, which flows from our pole in fummer 

 with fo much rapidity, and which is lo violent towards its 

 fource, crofles the equinoctial line, its flux not being fiemmed 

 bv the effufions of the fouth pole, at that feafon confolidated 

 into ice ; it extends beyond the Cape of Good Hope, and 

 being directed call, by the pofition of Africa and Alia, forces 

 the Indian ocean into the fame direction, and may be con- 

 sidered as the prime mover of the vveftern monfoon, which 

 takes place in the Indian feas in April, and ends in September. 



The general current, iOiiing during our winter from the 

 6 foutb 



