Drainage hj Steayn Power. 



165 



From the foregoing levels it will be seen that the ordinary 

 lift" of the water-wheel, when the water in the sluice is level 

 with the breastwork of the wheel, is 5 ft. 4| in. (viz., 7 ft. 9i in. — 

 2 ft. 4^^ in.) ; it happens, however, that frequently during winter 

 the water in the sluice stands at 9 ft. 6 in., so that in fact the lift 

 at this season may be averaged at 7 ft. 1^ in. 



Reasons for fixing upon the present Site of the Engine. — 1. The 

 level of the ground at the engine and near it (referring to the 

 Ordnance datum) is 12 to 13 feet, which is from 3 to 4 feet 

 higher than most of the land along the line of sluice up to which 

 it was desirable the engine should be placed. At this height, 

 therefore, the work of erecting the buildings and the engineers 

 cottage could go on without fear of flood. 



2. The foundation here was also good, being a bed of marl of 

 several feet deep. 



3. There is a good public road close to, by 

 which the materials for building and the coal 

 for the engine could be easily got to the spot. 



4. The site is nearly equidistant from both 

 extremities of the land requiring to be drained ; 

 so that the water reaches the engine in one half 

 the time it otherwise would do if the engine 

 were at the west end — that next the sea, and the 

 most natural point of outfall. 



Other reasons might be given in favour of the 

 present site, but it is considered unnecessary to 

 state them. 



Statistics relating to the Drainage and Rain- 

 fall. — The engine commenced working for the 

 first time on the 9th of April, 1850, but it was 

 not until the 29th of March, 1851, that a regu- 

 lar account was kept, by which the quantity of 

 water lifted could be calculated. The mode 

 adopted for ascertaining this fact, is, I think, 

 deserving of notice. The depth of the water in 

 the v/heel-race is ascertained by fixing in the 

 w^heel-house up to the wall near to where the 

 water enters the building, a gauge or graduated 

 rod, which is acted upon by a round zinc float, 

 and indicates in feet and inches the exact depth 

 of the water in the wheel-race. This will, perhaps, 

 be better understood by reference to the drawing 

 in the margin. The depth of water is noted by 

 the engine-man soon after he commences work- 

 ing, and afterwards throughout the day, at inter- 

 vals of generally two, but sometimes three hours. 



5.0 



Zinc 





Float. 



























