44 KKNDAM. : OHSKHVATIONS ON THK (iLACIER LAKES. 
Howe Beck, near Castle Head Farm (see Fig. 9 and Plates XII. and 
XIV.). The moraine, which in all probability marks tlie furthest 
extension of tlie ice, attains an altitude of just over 450 feet above 
sea-level, yet tlie ice which produced it not only surmounted the 
lofty cliffs moie than (HX) feet high at Peak, but oveirode hills 
of 80() feet altitude in the intervening ground. 
Anotliei- ratlier different apphcation of tlie same principle 
explains wliy no marginal channels are visible on the hills south 
of Sla])ewath. two miles E. of Guisborough (see Fig. 12) ; 
tlie outstanding mass of Airy Hill (to the west of Boos Beck, in 
Scale _ ? ' ■ : Miles 
Fig. 12. 
MAI' OF THE lioOS liKCK VALLEY, SlloWlNc; THE DEVIATION 
OF THE STREAM AT SLAl'EWATH. 
Fig. 12) acted as an effective fender to keep the ice away from 
the main slope of the Cleveland Hills, so that a sinuous lake would 
lie along their front, probably extending further to the westward 
