Drainage by Steam Power, 57 



working night and day at 10^. 6^. each a week with coals for 

 a fire ; add the expense of repairs, grease, and all together 

 will amount to 2/. per cent, with 1000/. first cost Mr. Eckard, 

 of Chelsea and Dover Street, was the engineer. It drains 

 1900 acres. Two years ago the floods overtopped the banks 

 and it cleared the water out so quickly that not a single year 

 was lost/* 



Previous to the complete drainage of Lake Haarlem, the 

 rainfall from 75,357 acres of Polder Land was lifted into the 

 low part, or JBoezem, by two hundred and sixty-one large 

 windmills, of an aggregate force of 1500-horse power. The 

 complete drainage of this lake was subsequently effected by 

 steam power, a full account of which will be given further on. 

 In 1776 the first attempt was made in Holland at using steam 

 power in place of windmills for drainage purposes. A pump- 

 ing station and steam engine was erected at Arkelschendam, 

 near Rotterdam, and another at Mijdrecht in 1792. These 

 engines worked bucket pumps actuated by rods attached to 

 chains which rode on an arc at the end of a large rocking 

 beam, the piston-rod being similarly attached at the other end 

 of the beam. As these engines consumed 31 lb. of coal per 

 horse-power per hour, the use of steam did not extend much, 

 as it was thought that steam could not be used economically. 

 In 1825 steam power was used at Zuidplas to drive two Archi- 

 medean screws for lifting water a height of about 22 feet 

 These engines consumed 22 lb. of coal per actual horse-power 

 per hour. This lake was emptied by the united action of 

 thirty windmills working scoop wheels and the two steam 

 engines in 1840, and subsequently kept dry. Each steam 

 engine raised the water from 2352 acres to a height of 3*28 

 feet. Each windmill with its scoop wheel raised the water from 

 1898 acres for the first half of the upper lift to a similar height, 

 and from 2656 acres for the second half. The annual cost of 

 maintaining these thirty mills amounted to 60/. per mill 

 These mills were superseded by steam in 1871. 



