340 GENERAL OBSERVATIONS. 



three to five hundred yards, throughout that extent, and 

 in most parts bristled Avith rocks. The banks, between 

 which the water is thus hemmed in, are, for the whole of 

 this distance, every where precipitous, and composed en- 

 tirely of masses of slate; which, in several places, run in 

 ledges across from one bank to the other, forming rapids 

 or cataracts, which the natives distinguish by the name of 

 Yellala. The lowest and the most formidable of these 

 barriers was found to be a descending bed of mica slate, 

 '.vhose fall was about thirty feet perpendicular in a slope 

 of 300 yards. Though in this low state of the river it was 

 scarcely deserving the name of a cataract, it was stated 

 by the natives to make a tremendous noise in the rainy 

 season, and to throw into the air large volumes of Avhite 

 foam. Even now the foam and spray at the bottom are 

 said to have mounted eighteen or twenty feet into the air. 

 On visiting this Vellala, Capt. Tuckey, Professor Smith, 

 and Mr. Fitzmaurice were not a little surprised to observe, 

 how small a quantity of water passed over this contracted 

 part of the river, compared with the immense volume 

 which rolled into the ocean through the deep funnel- 

 shaped mouth ; the more so, as they had previously as- 

 certained, in their progress upwards, that not a single tri- 

 butary stream of water, sufficient to turn a mill, fell into 

 the river on either side, between the mouth and the ca- 

 taract; and they concluded, that the only satisfactory 

 explanation of this remarkable dift'erence in the quantity, 

 was the supposition that a very considerable mass of water 

 must fmd its way through subterraneous passages, under 



