History of Sanitation

78 HISTORY OF SANITATION water by means of engines. It remained for Hanover, Germany, to install the first pump of which we have knowledge, for supplying a town or city with water. In Germany, waterworks were constructed as early as 1412, and pumps were introduced in Hanover in the year 1527. In London, England, the first pump was erected on the old London Bridge in 1582, for the purpose of supplying the city with water from the Thames and distributing it through lead pipes. There are only meagre accounts of the Hanover and London Bridge pumps to be had, however, and no illustrations showing their construction. The oldest known print of a steam engine is in the Birmingham public library,* and shows a machine built in 1712 by Savery and Newcomen. A search made by The Engineer of London, has brought to light an old engraving dated 1725, and entitled “The Engine for Raising Water by Fire.” It is unique in containing the first illustrateddescription of a steam engine. This machine is somewhat dif- ferent from that portrayed in earlier engravings, for the boiler is fed with a portion of the hot water coming from the bottom of the cylinder or hot well. This fixes the date of the improvement described by Desagaliers in his Ex- perimental Philosophy as follows: “It had been found of benefit to feed the boiler warm water coming from the top of the piston, rather than cold water, which would too much check the boiling and cause more force to be needful. But after the engine had been placed some years, some persons concerned about an engine, observing that the * Engineering. Record, Oct. 21, 1905