Travelers 9 Original Accounts: 1801-1840 



say, than a man's fingers and thumb, brought as nearly to a 1827-28 

 point as possible. The conical tails which stream from these 

 watery meteors may vary from one or two yards to ten or twelve, 

 and are spread out on all sides in a very curious manner. 



The lower part of the Fall, it must be observed, is so con- 

 stantly hidden from the view by a thick rolling cloud of spray, 

 that during ten days I never succeeded once in getting a glimpse 

 of the bottom of the falling sheet; nor do I believe it is ever 

 seen. Out of this cloud, which waves backwards and forwards, 

 and rises at times to the height of many hundreds of feet above 

 the Falls, these singular cones, or comets, are seen at all times 

 jumping up. The altitude to which they are projected, I esti- 

 mated at about thirty feet below the top ; which inference I was 

 led to by means of the sketches made with the Camera Lucida. 

 I watched my opportunity, and made dots at the points reached 

 by the highest of these curious projectiles. The whole height 

 being between 1 50 and 1 60 feet, the perpendicular elevation to 

 which these jets of water are thrown cannot, therefore, be less 

 than 1 1 or 1 20 feet above the surface of the pool. 



The controversy respecting the elasticity of the air behind the 

 Fall, was soon settled. I carried with me a barometer made 

 expressly with a view to this experiment. It was of the most 

 delicate kind, and furnished with two contrivances absolutely 

 indispensable to the accuracy of experiments made under such 

 circumstances. The first of these was a circular spirit-level 

 placed on the top of the frame holding the tube, by which the 

 perpendicularity of the instrument was ascertained ; and secondly, 

 an arrangement of screws near the point of support, by which 

 the tube, when duly adjusted, could be secured firmly in its 

 place. By the help of these two inventions of Mr. Adie of 

 Edinburgh, this instrument can be used with confidence, although 

 exposed to such furious storms of wind and rain, as that I have 

 just been describing. These simple additions to the barometer, 

 it may be mentioned, give great facility to observations made for 

 the determination of the height of mountains, as it secures the 



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