KRFALLS. 



WATERFALLS. 



diversion or obstruction of water U of a permanent nature and injurious 

 to UM reversion, an action may be brought l>y the re\ ersioner, sa well 

 as by the tenant in possession, each for hit renwctire lot*. 



The diversion of watercourse* or injury to their bank* to at to cauM 

 inumlatioo are nuisance* against which a court of fruity will protect 

 partte* by injunction ; and if there be a question as to the right t,, tin- 

 flow of water, an issue will be directed to try it Although a court of 

 equity will not in terms decree the banks of riven, watercourses, or 

 navigable canals to be repaired, the effect of such an order may be 

 obtained by an order that parties shall not be at liberty to use them 

 while out of repair, or against their impeding the use of them by the 

 obstructions consequent upon a state of disrepair. An injunction may 

 also be obtained against conducting the water from one man's tene- 

 ment upon that of another to his injury by drains or otherwise, in a 

 manner in which it has not been accustomed to flow. And it may be 

 laid down generally, that, with respect to water and watercourses, the 

 aid of a court of equity may be obtained for the purpose either of 

 restraining injury or of quieting possession. 



WATERFALLS. In the article VALLKTS we have arranged 

 general view of the main features of the earth's surface, and a series of 

 inferences touching the forces whereby the diversified forms of hills 

 and valleys have been occasioned. But these forms, though on a large 

 scale they appear permanent, because the great modifying agencies' 

 which produced them have passed away, are really undergoing continual 

 change from causes in daily operation. The moat solid stone is wasted 

 by the feeble but unceasing power of decomposition possessed by the 

 atmosphere. Rain washes away the disintegrations occasioned by 

 varying temperature and chemical processes ; the hills lose and the 

 valleys gain, and the balance of decay and renewal of land is only 

 finally adjusted on the shores and in the basin of the sea. Among the 

 phenomena which show this mutability of the supposed solid land 

 with most distinctness, are interruptions to the general uniformity of 

 the inclinations of valleys and the even slopes of hills : for these 

 changes of slope are .points of variation of the intensity of the agencies 

 excited by the slope. These interruptions of uniformity are all 

 referable to the unequal power of resistance which rocks of different 

 hardness, or dissimilar position, or unequal thickness, or unlike modes 

 of association present to external agencies. Thus have U.-M (Win. .1 

 round the high limestone hills of the northern counties a series 

 of rocky terraces, not lean regular than the escarpments made by 

 military art ; and thus the oolitic ranges of the CoUwold show 

 horizontal mounds of sand and cliffs of stone above the broad plains of 

 lias clays and red marls which margin the Severn and the Avon. On 

 these grand features of the earth's surface the action of the atmosphere 

 (including chemical and mechanical operations) produces only slight 

 modifications ; but when the terraced slopes in their flexures round the 

 hills turn into the valleys, a new agency is brought to work upon them. 

 Rivulets, however small in quantity, and torrents, even such as are of 

 only temporary energy, exert a positive influence in wasting and trans- 

 porting away earthy materials ; and these effects rise to a maximum 

 wherever, from any of the causes already alluded to, the surface of the 

 earth presents successive points of less and greater power to resist the 

 action of running water. Wherever, in a valley whose slope is con- 

 siderable, the rocky masses successively crossed by the stream arc of 

 very unequal hardneu, as, for example, when solid limestone is found 

 resting on soft shale or feebly indurated sandstone, a more than 

 ordinarily rapid current is occasioned over the lower beds of the lime- 

 stone into the iipjmr beds of the shale. This difference of slope in the 

 running water is of a nature to increase continually to a certain 

 depending on the relative firmness and thickness of the hard and soft 

 rocks, the inclination of the valley, the magnitude of the stream, and 

 other less important particulars. Thus rapids and cataracts ore formed ; 

 and where the conditions combine in the most favourable degree water- 

 falls, to use that term in a more specific sense, are produced. 



The character of these varies according to the disposition of the 

 yielding and resisting portions of the rocks. Wherever stratification is 

 absent, as in granite, or concealed, as in some metamorphic slates, the 

 main features of the waterfall are determined by the direction of t In- 

 natural joints in the stone. Hence the picturesque character of the 

 falls of the Bruar (Highlands), Lodore (Cumberland), and the Rhcid- 

 diol (North Wales). In some cases these natural joints yield in parallel 

 hoes, and give a deep narrow passage to the water. Scale Force, in 

 Cumberland, is an example. But the most interesting, if not the 

 most picturesque, class of waterfalls, is occasioned by the stratified 

 rocks ; and the most curious of them are observed where hai 

 stones or gritstones rest upon yielding shales or soft clays, 

 continual action of the stream, the shales, kept constantly damp, 

 crumble and fall away even at considerable heights and distances from 

 the points where they are touched by the water. Thus, a hollow space 

 is formed beneath the limestone which crowns the i 

 proceeds so far as to reach at last some of the natural joints which 

 divide the rock. Tin n the limestone falls down, the waterfall recedes, 

 and the process of removal and destruction is renewed. Thus, on the 

 ides of the hills, in the limestone dales of tl.. unties of 



England, the waterfalls are daily receding up the streams, and thus are 

 the Falls of Niagara forced continually farther up tin- river. 'I 

 cess is by no means slow. Beneath Hardrow Force, in Y,.ikshire (a 

 fall of 9U feet), the effect since the general valley of the Yoro was exca- 



vated by other force* ha* been to produce a sinuous glen within steep 

 vertical walla of rock, at the foot of which yet lie great heaps of fallen 

 material*, v. hi, li the- feeble stream that formed the glen has not been 

 powerful .n K.ir .in account of the natural processes 



!;, uli i-li tl. lieen displaced, and are utill mi.l. r- 



going change, the volumes of Sir C. I.yell (' Principles of Geol 



tli.- former of which are instructive on 



all points connected with the operations of running water) -may be 

 consulted. Exactly such effects as are here attributed to m 

 streams happen on the sea-coasts where rocks of a particular i 

 occur under analogous circumstance*. 



The physics of waterfalls have received but little attention. though 

 it might have been anticipated that they must involve c-:- 

 of an interesting nature, nn.l of some philosophical importance ; fur in 

 them we have the principal cases in nature of the mechanical agi> 

 nn.l division of water, resulting chiefly from its own inertia, gi 

 and momentum. In the greatest waterfall in Kurope, for example, the 

 Voring FOB, near the Hardanger Fiord, in UY-u-ni Norway, we 1 

 very large body of water, and a clear faU of 900 feet. It descent* 

 into a narrow bare chasm, the sides of which are very nearly ] - 

 dicular. " The spray dashes up from below with such 

 another waterfall, which descends on the opposite side of tin- chaMn, 

 is actually stopped by it and dispersed before it can reach the l>" 

 (II. F. Tozcr, ' Vacation Tourists in I860.') 



The late Captain Basil Hall, in his 'Travels in North An, 

 thus describes the involution of air in the Horse-shoe Fall of Niagara, 

 and its subsequent disengagement. " This enormous cataract, 

 descent, like every other cascade, carries along with it a quan; 

 air, which it forces far below the surface of the water, an experiment 

 which any one may try on a small scale by pouring water into a 

 tumbler from a height. The quantity of air thus carried down by BO 

 vast a river as Niagara must be great, and the depth to which it is 

 driven in all probability considerable. It may also be mud 

 by the pressure ; and it will rise with j.j, nee both on 



the outside of the cascade, and within the sheet or curtain whicli 

 the cataract." He mentions also the blast of wind which rises : 

 ingly from the pool on the outside of the sheet. To the explosion, as it 

 may bo termed, of the bubbles, thus constituting 1 1 . 

 pel j>ctuajly renewed accumulation of bursting fr.iili. scribe 



the greater part of the sounds which combine to produce the i 

 the Niagara falls. In doing this we apply to the subject the observa- 

 tions of Professor TyndaU, on the sound of breakers and the roar of 

 the ocean. ('Vocation Tourists in 1800,' p. 307, note.) The i; 

 of water against water, he has shown, is a comparatively suborilinate 

 source of sound; though in this cose, from the enormous mosses of 

 water concerned, and the momentum which those of the river a- 

 from the height from which they descend, the sounds proper 

 impact must be very considerable. The sonorousness of tli, 

 agrees with this ascription of it, principally, to the violent imp 

 air against air, the air impinged upon being that of the free atmo- 

 sphere, by which the sound is communicated to the ear. The ex- 

 plosions of the bubbles must take place, in many instance ~. 

 enormous force, owing to the resistance presented by the immense 

 cohesive power of films of water, and occasion corresponding loudnes* 

 of the sounds, which, however, in coalescence and rapid succession 

 are heard as an interminable roar. 



To these, no doubt .enormous bubbles of condensed air, rushing 

 upwards to the surface of the pool, and expanding as tl 

 must also probably attribute the production of the sharp-p' 

 cones of water which are continually projected upwards from the pool, 

 on the outside of the fall, sometimes to the height of a hundr. 

 ten or twenty feet They are further described by (.'apt.iin 11^11 lh", 

 however, expresses no opinion as to their origin), as resembling some 

 comets in form, their point, or apex, which is always turned IM 

 being quite sharp, and not larger, he estimates, " than a man's 1 

 ami thumb, brought as nearly to a point as possible. The conic 

 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 01 



r." The actual production of these cones, and their emergence 

 In mi the surface of the pool, which must be their beginning above 

 water, if the origin here ascribed to them be the true one, are con 

 by the clouds of spray in which the bottom of the falling sheet is 

 constantly hidduu from the view. Out of this they are at all times 

 seen darting up. 



This cloud or mist of spray is itself an interesting phenomenon, 

 characteristic more especially of great falls, like thone of Niagara, 

 uniting depth of fall and ipi.-tntity of water. It arises from the l> 



i tin- iloecndiiu; upon the Mill <T merely flowing 

 water takes place; and it involves several physical c, 

 which ,"ticc. As produced by the Niagai.' 



its extent and vi.-il'iniy from a distance have often been 

 The lower port of the great fall, according to Captain li. II 

 always concealed by this rolling cloud of npi .1 . , which waves back 

 and fin m*S to the height ol in. my hundred i. -i-i 



Consisting ol thick VOI 



of whitish n much the appearance of smoke rising 



heaps . weeds ; such smoke, it may bo added, itself consist- 



ing principally of steam condensed into globules of water, or steam- 



