NAT URAL HISTORY oi NORWAY. 93 



SECT. XIII. 



At air/ great diftance from the lea, the rivers of Norway are Great advan - 

 __t navigable for veflels of considerable burden \ for though in waters for 

 many places, there be a Sufficient depth of water, yet the water- and forward- 



m r 1 , -1 • t ■. -..,- ~ - ing the 



falls, caufed by the intervening rocks and clifts, are unfurmountable tlmb«! 

 obftacles, the ilream precipitating itfelf from a height of 6, 8, or 

 10 fathoms, where only mafts and fuch timber can be floated down, 

 and many of thefe are deflroyed; yet the greater!: part get fafely 

 through, and being marked by their owners, are fecured at the s ee plate VII , 

 Lentzes. Thefe are large booms, fortified with iron bolts, and 

 laid acrofs feveral parts of the river for flopping the timber. The 

 breaking of a Lentz is of fuch ill confequence .to the timber- 

 merchants, that in 1675 fach an accident which happen'd by an 

 inundation of the Glommen, occafioned many bankruptcies among 

 them *.■ As thefe and other rivers perform the capital fervice of 

 conveying from the mountains and forefts thofe mafts and timbers, 

 which without fuch conveyance would be abfolutely ufelels with 

 refpect to commerce, fo by their feveral waterfalls they are of a 

 further 1 utility, in driving feveral hundred law-mills, where, with 

 little labour, planks and boards are fawed to all dimenfions. 



SECT. XIV. 



The vaft force of rivers in feme mountainous countries, where 



WeltfiF- falls' 



the fall from lofty rocks redoubles the motion of the water, from the 

 may in fome meafure be conceived from what I have already re- rivers - 

 la ted of the fudden fubterraneous courfe of the river Gule, and the 

 inundation occafioned by the fubfequent eruption. But I lhall 

 here add another inftance of this kind frill more wonderful, which, 

 according to the authentic account from whence it is taken, hap- 

 pened in the year 1702. I mean the fudden immerlion of the fa- 

 mily feat of Borge near Friderickftad into a deep abyfs. The par- 

 ticulars of this unhappy and lingular accident may be read in the 

 ' nova iiteraria maris baltici ad ann. 1703. maj. p. 3. where is an- 

 nexed a draught of the fituation of the place. In the night of the 



* The yearly charge of fuch a Lentze or Boom, may in fome places amount to 

 three or four hundred Rix Dollars, but in return it yields to the owner no lefs than 

 a thousand or eleven- hundred, for at leaft thirty thoufand dozen of large pieces of 

 timber pafs through it, of which each makes fix or eight planks, 



2 fifth 



