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PHYSICAL GEOGRAPHY. 



his comedy of the " Old Bachelor " and a part of his " Mourning Bride." In Spain a 

 similar phenomenon is exhibited by the Guadiana ; but it occurs under different circum- 

 stances. It disappears for about seven leagues an effect of the absorbing power of the 

 soil the intervening space consisting of sandy and marshy grounds, across which the 

 road to Andalusia passes by a long bridge or causeway. The river reappears with greater 

 power, after its dispersion, at the Ojos de Guadiana the Eyes of the stream. 



Many rivers are subject to a considerable elevation of the level of their waters. This 

 is periodical or irregular in its occurrence, according to the nature of the producing 

 cause. Casual temporary floodings, as the effect of extraordinary rains, are common to 

 the streams of most countries, and sometimes occasion great changes of the surface, and 

 destruction of life and property. One of the most remarkable instances of this kind in 

 modern times, occurred on the 4th of August, 1829, in Scotland, when the Nairn, Spey, 

 and Findhorn rose above their natural boundaries, and spread a devastating deluge over 

 the surrounding country. The rain which produced this flood fell chiefly on the Monadh- 

 leadh Mountains, where the rivers in question have their feeders, situated between the 

 south of Loch Ness and the group of the Cairngorums. Sir Thomas Dick Lauder, in his 

 interesting account of this inundation, considers the westerly winds, which prevailed for 

 some time previously after a season of unusual heat, to have produced a gradual accumu- 

 lation of vapour, somewhere north of our island ; and the column being suddenly impelled 

 by a strong north-easterly blast, it was driven towards the south-west, till arrested in its 

 course by the lofty mountains upon which it discharged itself in torrents perfectly unex- 

 ampled. The rain fell occasionally in heavy drops, but was for the most part broken by 

 the blast into extremely minute particles, so thick, that the very air itself seemed to be 

 descending in one mass of water upon the earth. It deluged every house whose windows 

 were exposed to the south-east. The lesser animals, the birds, and especially game of all 

 kinds, were destroyed in great numbers, by the rain alone ; and the mother partridge, with 

 her progeny and mate, were found chilled to death amidst the drenching wet. At Huntly 

 Lodge, according to an accurate observation, between five o'clock of the morning of the 

 3rd of August and the same hour of the succeeding day, there fell 3J inches of rain, or 

 about one-sixth of our annual allowance of rain descended there in twenty-four hours. 

 This was at a considerable distance from the mountains the central scene of the rain 

 where its quantity must have been prodigiously greater, sufficient to account for the 

 tremendous flood that followed, far exceeding in its rise, duration, and havoc, any other 

 that ever affected the same locality. The Findhorn and Spey assumed the appearance of 

 inland seas ; and, when the former began to ebb, a fine salmon was driven ashore and 

 captured, at an elevation of fifty feet above its ordinary level. Most of the rivers of the 

 temperate zones are subject to these irregular floodings from the same cause, especially 

 those which take their rise in high mountain regions, the St. Lawrence being the most 

 remarkable exception, the level of which is not affected by either rains or drought. The 

 vast lakes from which this river issues, furnish its channel with an inexhaustible supply 

 of water, and present a surface too extensive to be sensibly elevated by any extraordinary 

 rains. A strong westerly wind, however, will affect the level of the St. Lawrence, and 

 occasion a rise of six feet in the waters to the eastern extremity of Lake Erie. An 

 easterly wind also upon the Orinoco will check its current, elevate the upper part of the 

 stream, and force its waters into the channels of its tributaries, giving them a backward 

 flow, and causing them to be flooded ; and a northerly wind will drive the Baltic up the 

 mouths of the Oder, and raise its level for a considerable distance. In a similar manner, 

 the Neva rises when a strong wind blows from the Gulf of Finland ; and that occurrence, 

 taking place coincidently with high water and the breaking up of the ice, would create an 

 inundation sufficient to drown the whole population of St. Petersburg, and convert that 



