flows into another reservoir, wlience it is conducted in pipes back 

 to a great culvert, the position of which may be known by a 

 broad iron pLate in the walk facing the Memorial on the soutli 

 side of Mr. Nesfield's circular composition of gTavel-beds in front 

 of the great basm. This large culvert — up which a man might 

 walk, and which, to continue the comparison of circulation, may 

 be likened to the vena cava — receives all the water on its return 

 from the four canals, and conveys it back to the Appold pump. 

 That pump connects, or stands between, the two ends of the 

 pipes, as the lieai-t does between the veins and arteries, and, like 

 it, draws the circulating fluid out of the one and throws it into 

 the other. It does so by the excessively rapid revolution of a 

 fan, which wliirls the water round, exhausting it from the one 

 pipe and forcing it into the other. By this means the whole of 

 tlie garden waterworks are set in motion at once ; and 5000 

 gallons are passed through the pump every minute. In two 

 hours time it would exhaust the whole water in the canal and 

 basins, which it takes the small engine four days and four nights 

 constant working to fiU. The ordinary purpose for which the 

 Appold pump is used is merely to draw water out of one ptipe ; 

 the forcing it into the other pipes is an additional appHcation 

 of the pump to another use. 



The Appold pump is the work of one of those mechanical 

 geniuses of whom England has produced more than any other 

 nation. It is rather more than twelve years since, that Mr. 

 Ap>pold, on a visit to Cornwall, saw the steam cylinders which 

 were being prepared there for the purpose of draining the 

 Haarlem lake in Holland. These central steam cyHnders, 12 

 feet in diameter, were to work several pumps around. One set 



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