210 Limits ofpef'pefual Snow in the North. [Marcit, 



But the ocean may be considered as composed of an Infinite num- 

 ber of such columns, and therefore the waters must accumulate by 

 a progressive swell, from the quadratures to the equator, to balance 

 the progressive increase of pressure from the equator to the qua- 

 dratures.* 



This theory has the advantage of simplicity, and simplicity, the 

 offspring of unnerring wisdom and almighty power, is in general 

 the companion of truth. It is also certain, that the cause to which 

 the effect is attributed does exist, and that it must produce such an 

 effect. If then the effect is equal to the phenomena of the anti- 

 lunar tide, it must be the true and the only efficient cause ; for 

 another equal cause would produce a redundant effect. 



On the principles above explained, the lunar and antilunar tides 

 would coincide in all their appearances, and be of equal magnitude 

 were their distances from the moon equal. Their difference, there- 

 fore, must be in proportion to the difference of the squares of their 

 mean distances from the moon, and no more. The antilunar tide 

 is produced by a force weaker than that which produces the lunar 

 tide, as 1 is to 30, or thereabouts. If the medium lunar tide 

 therefore be 10 feet, the antilunar tide on these principles will be 

 9 feet 8 inches. 



Article X. 



On the Limits of perpetual Snoiv in the North. By Leopold Von 

 Buch, Fellow of the Royal Academy of Sciences in Berlin. f 



For the first and only information which we possess respecting 

 the limits of perpetual snow in the north, we are indebted to that 

 eminent and able philosopher, Mr. Esmark of Kongsberg. It was 

 made known in 1803, in the Danish newspapers, and in a later 

 period in the Northern Archives for Natural History. {Nordischeit 

 Archiv fur Natnrkimde,) by Professor Pfaff. Mr. Esmark in- 

 forms us in that notice, that on the north and north-east declivities 

 of Norway, he had observed the line of perpetual snow at the 

 height of 3000 feet above the level of the sea, while on the south 

 and west declivities of the same country, its height was no less 

 than 7000 feet. This demonstiates that even in high latitudes 

 this limit is still considerably elevated above the level of the sea. 

 But the question in some measure still remains; What degree of 

 latitude in Norway corresponds with this determination ? For the 

 land stretches from the 58th to the 71st degree of latitude. Neither 



. * This illustration is commonly applied to the Newtonian theory, and correctly 

 too, because tlie Newtonian theory is equally founded on the difference in gravity 

 between the equatorial and polar waters. The error lies in tins, that it ascribes 

 that did'erence to a greater diminution of gravity, whereas it truly arises from a 

 smaller addition. 



f Translated from Gilbert's Aunalen der Physik, for 1812, vol. xli. p. 1. 



