••562 



WATER-TRANSPORT. 



(a) Earth-dams. — Earth-dams are formed of heaps of earth 

 at the ordinary angle of repose for the material used, as shewn 



in fig. 202, which gives the section of such a dam. A facing 

 (a) of clay or loam is added to the dam on the side near the 



Fig. 203. 



The ^tartin's dam in tlie Bavaiian-l'olieini.in Foich^t 

 masonry. 



wlikli ]ia.s now been rebuilt in 



