&3& bii the Stowage and Sailing bf Ship^* 



as it would have the same effect, and give considerable rdief 

 to the fore extremity. 



There is one part of Professor Inman's observation — ** or by 

 bringing the ship more by the head or stern, thus adjusting the 

 seat of the ship in the water to the masting, as it is," which 

 it appears to me can only be meant as a temporary expedient, 

 and till an opportunity offers to alter the masting, as it would 

 be sacrificing a very material point — the proper seat of the 

 ship in the water. 



J. P. 



Plymouth^ Nov. 22, 1828. 



On the Elevation of TVater by the momentive Force of that 

 Fluid in the Suction Pipe of a Pump. Communicated by 

 R. Addams, Esq. 



The principle upon which the action of the water-ram (belier 

 hydraulique) depends, is known to the readers of this Journal * ; 

 but I am not aware that any one has, publicly, noticed or ob- 

 served the same principle producing a similar effect without a 

 fall or head of water. I am, therefore, inclined to suppose the 

 following description of a hydraulic operation, which I have 

 lately witnessed, possesses sufficient novelty to constitute an 

 admissible article in the Journal of Science and the Arts. 



In the water-ram, the momentum is generated in proportion 

 to the velocity of the water ; and the velocity is dependent upon 

 the fall : but it is obvious the same effect would take place 

 from the same momentive force, in whatever manner this force 

 may originate. 



Now, when a common pump is worked and drawing water 

 from a well, the air presses the water through the ingress or 

 suction-pipe with a certain velocity: the moving water in that 

 pipe will have a proportionate momentum ; and if it be suddenly 

 checked it vvill exhibit its force as in the water-ram. This 1 

 have seen verified in a pump at the house of Mr. Balaam at 

 Clapham. I was requested to examine it, and explain its 

 action. . • 



* Journal of Science, Vol. I., 0. S. 



