SIR WILLIAM SIEMENS, f.R.S. 277 



very simple construction, which is represented in Fig 1, Plate 24. 

 It consisted of a mould or double bucket A, that is divided 

 equally by a division B, and is at liberty to rock upon a centre C. 

 Perpendicularly above this rocking centre is the open mouth of 

 the supply pipe D, filling alternately the one and the other bucket. 

 At the extremities of the buckets, small pockets E E are provided, 

 that fill at the instant the mould overflows, and being at the 

 greatest distance from the rocking centre, cause the filled bucket 

 to overbalance the empty one, and to discharge itself into the 

 cistern F below. The supply of water is regulated by means of a 

 float G, and a cock H, as will be readily understood. The rocking 

 shaft C gives motion to a counter that is not shown, by means of 

 a ratchet and wheel. 



Mr. Parkinson, of London, has invented a bucket meter, 

 similar in its construction to the ordinary gas meter, which is 

 found to register the water passing through with great accuracy, 

 and is actually used to a great extent in connection with receiving 

 cisterns. 



It would be interesting to add to the list of bucket meters, 

 contrivances both cheap in construction and capable of measuring 

 liquids with accuracy, were it not that these meters destroy the 

 onward pressure of the water, and are of necessity incumbered by 

 cisterns at elevations above the premises supplied, which cisterns 

 entail great expense and inconvenience. 



The name " Piston Meter " is intended to comprise all meters in 

 which the fluid is measured by displacing a piston, a disc, or a 

 diaphragm, and thereby filling a measured cavity. 



The " piston meter " in this respect resembles the " bucket 

 meter," with the advantage of 'transmitting the onward pressure 

 of the water, and of dispensing with the necessity of a cistern. 

 On the other hand it labours under great and peculiar dis- 

 advantages, partly on account of the valves and pistons which are 

 employed being quickly destroyed by the sand and other impurities 

 contained in the water, or broken by its impact against them, and 

 partly on account of their great bulk and expense in proportion to 

 the water measured. 



It will only be necessary to mention a few of the multitude of 

 piston meters that have been proposed, for the sake of illustration. 

 Those of Lewis and Taylor, both of Manchester, and of Messrs. 



