Index. 



175 



V. 



Velocity of water in open drain, 1 1 



mean, 13 



formula for ascertaining, 12, 



160 



scoop wheels, 83 



Vernatts drain, deepening by scour, 



20 

 Vistula, river, 19 

 Vreedenberg, A. C. J., trials of 



pumps, 136 



W. 



Waldersea drainage district, 50 

 Water, quantity to be raised by 

 pumping engines, 64 



table, 162 



raised by scoop wheels, 



82 



due to rainfall, table, 162 



transporting power of, 18 



. sediment carried in suspen- 

 sion, 19 



motion of, 10 



velocity of, in open channels, 



II, 161 



through bridges and 



sluices, 32, 1 60, 162 



— pressure of, 160 



— inclination in surface, 14 

 machines used for raising, 50 



Waterland, pumping station at, 152 

 Watt & Co., machinery erected by, 

 109, 114, 130 



Watt &: Co., trials of, as to dis- 



charge of wheels, 115 

 Weeds, obstruction from, 13 



in river Hull, 1 3 



removal of, 17 



Weights and measures, 158 



French, 159 



Welland, river, deepening by scour, 



21 

 Wells, use of Appold pump, 93 

 Welsh, E., trials of Lade Bank 



engines, 112 

 Wexford Harbour, cost of running 



pumps, 54 



drainage stations, 131 



Wheel pumps, 74, I49 

 Wheler, W., scoop wheel, "jo 

 Whittlesea Mere, use of centrifugal 



pump, 93 



pumping station, 1 1 8 



Windmills, use of, for drainage, 55, 



56, 57 

 for draining Lake Haarlem, 



141 



Zuidplas Polder, 150 



Witham drainage, 4 

 river, 19 



Y. 

 Young, Arthur, description of wind- 

 mill in fens, 56 



Zuidplas Polder pumping station, 

 57, 150 



LONDON; FKINTED BY WILLIAM CLOWES AND SONS, LIMITED, STAMtORD STREET 



AND CHAKING CROSS. 



