A PREHISTORIC WATER-SYSTEM. 541 



The oldest of the canals dato unquestionably from pre-Roman 

 times. The *' Roth " Canal supplies three villages with water, and is 

 19,200 metres (more than eleven miles), or four hours and twenty- 

 three minutes long. It starts from " La Plaine Morte " glacier, on the 

 Weisshom, 2,673 metres above the sea, crosses several clefts, is con- 

 ducted through a tunnel more than three hundred metres long, is cov- 

 ered for 9,600 metres, exhibits other features of high engineering 

 skill, has an average section of a metre and three tenths, and delivers 

 nearly a cubic metre of water a second. An artificial lake, or reser- 

 voir, has been built in the same district, to hold the water that is not 

 wanted for immediate use. Its water, however, has not the same 

 value as that taken directly from the glaciers, because it has lost 

 most of its mineral constituents by settling ; but, as it has become 

 thoroughly warmed, it is admirably adapted to those applications in 

 which water is wanted simply to refresh vegetation, and make the 

 soil more friable. 



The villages of Ried and Bietsch have three aqueducts (Kehr- 

 wasser, Bietscherriune, and Riederrinne), severally 8,400, 2,400, and 

 12,000 metres long, to bring down the muddy water from the great 

 Aletsch glacier, which are led for long distances along vertical cliffs 

 and over giddy chasms. At one point on the " Kehrwasser " three 

 men have been killed, within twenty-five years, by falling into the 

 gorge. The water of the Bietscherrinne issues foaming from a fear- 

 ful-looking chasm. The canal, having a border formed of stones laid 

 with sods, and masked by bushes from the Massa ravine that yawns 

 beneath it, is safe to walk along at first. The bushes soon disappear, 

 and the aqueduct becomes simply a wooden conduit, made of planks 

 that have to be drawn to the place, and adjusted there with great 

 danger, while the narrow, slippery gang-plank, which is the only walk, 

 offers but the most precarious footing to one who has to look down 

 through the high trestles or into the steep ravine of the wild Massa, 

 on one side, while he must watch on the other side lest he hit his head 

 against the overhanging rocks and lose his balance. The highest of 

 the three canals, the Riederrinne, is distinguished from the others by 

 its loftier rock-walls and deeper chasms. It reaches to the foot of the 

 Aletsch glacier, and draws the water from its source. Near it may be 

 seen older, abandoned canals. 



Near where these three canals start is the Marjulen Lake, having 

 its surface covered, even in summer, with floating ice. Its natural 

 outlet is by the valley of Viesch into the Rhdne, but occasionally, in 

 seasons of extraordinarily high water, it overflows in the opposite 

 direction, and pours its floods into the Massa, causing breaks in the 

 canals and stopping the conveyance of water. The existence of the 

 villages of Bietsch and Ried depends upon their obviating the mis- 

 chievous effects of these overflows, and it is customary to give a pair 

 of shoes to the mountaineer who first notifies the dwellers in the 



