354 EXPLANATION OF THE PLATES. 



c, Cover, screwed on the pipe. 



d', Gland, or stuffing box. 



e, Handle of the valve. 



f t Nozle with flanch for connecting the valve with the stop-cock of the injection pipe. 



g', Guard, so constructed as to form a grating, in order to prevent weeds or other 

 substances from being admitted into the condensers ; and having a socket rising 

 from the centre, through which the lower spindle of the valve passes. 



li ft, Two copper standards, screwed into the cover, having mortices or key ways 

 through them, which coincide in direction with a corresponding one in the rod; 

 and are so adjusted, that when the valve is completely open, a key passing 

 through them maintains the valve in its place, and thereby prevents its being 

 closed by the pressure of the water without rushing in to fill up the void in the 

 condensers. 



i, Key, or cutter, for fixing the valve as above. 



nit Ship's timbers. 



x, Planking of the ship's bottom. 



III. HAND-PUMP VALVES. 



These are the same as the Injection, with the exception of the grating. 



MANNER OF FIXING THE VALVES IN THEIR PLACES. 



The situation of the pipes being fixed, a close jacket of fearnought, well covered 

 on both sides with a mixture of white and red lead, is sewn on from the base to the 

 lower part of the screw, and a corresponding hole is formed in the ship's bottom. 



Then the pipe, being set up in its place by shores, is firmly screwed up by the 

 cover, and the space between the cone and a corresponding flanch of copper sheathing 

 (extending two or three inches up between the planking and the cone, to protect the 

 former from the attacks of the worm) is well caulked ; this done, a copper screw is 

 fitted through the lower part of the cone, into the wood, to prevent the possibility of 

 the pipe turning or heaving the cover on or off. 



The cover is now taken off, and the space around the upper part of the pipe is 

 caulked ; then it is finally replaced and screwed down on a copper washer of about 

 \ inch in thickness. 



The chocks are well coated on their under sides with red and white lead. 



