1845.] 



THE CIVIL ENGINEER AND ARCHITECT'S JOURNAL. 



177 



The dift'erent moiics of obtaining watiT from tho mains or pipes are 

 shown in the accompanying drawings. Fig. 2 is a section of a com- 

 mon pUig when not in ose. Fig. 3 is a section of the common plug, 

 with a canvas dam or cistern over it, as used in London.* The cistern 

 is made of No. 1 canvas.lj inches deep, extended at top and bottom 



Fig. 3.— Fire-plug with 



by J inch round iron frames, a double stay is hinged on the top frame 

 at each end. When the cistern is used, the toj) frame is lifted up, and 

 the stays put into the notches, in two pieces of hoop iron, fixed to the 

 bottom frame. There is a circular opening 9 inches diameter in the 

 canvas bottom, two circular rings of wash-leather about 2 inches broad 

 are attached to tlie edges of tiie opening in the canvas, so as to con- 

 tract it to 4 inches or 5 inches diameter; the plug being opened, the 

 cistern is placed over it, the wash-leather is pressed down to the sur- 

 face of the road by the water, and a tolerably water-tight cistern, with 

 about 12 inches or 11 inches of water in it, is immediately obtained. 

 Fig. 4 is a plug with a standcock in it, to which hose maybe attached. 



Fig. 4.— Plug, ivlth Slandcock. 



Fig. 5 is a common single firecock with a round water-way 2J inches 

 diameter. 



* Tile canvas dam is the Invention of Mr. Ilradlcy, for whlcb b 'wM aWBrded by the 

 Society of Am with a silver medal,— Ed, C.,E, f( A, Journal, 



1 .^. .\-Siiit;lt Fire-cock. 



Fig. G is a double firecock, as laid down in Her Majesty's Dock- 

 yards. 



Fig. C— Duuble F 



the Uoyal Dutkya 



It will be observed, that the short piece of pipe between the main 

 and this firecock is not curved to the current of the water, but merely 

 opened a little ; this is done with a view of increasing the supply by 

 steam power, and as the steam engines are, in most cases, situated in 

 a different direction from the tanks or reservoirs, therefore, the curve 

 that would have assisted the current in one direction, would have re- 

 tarded it in the other. It has been objected to these firecocks, that 

 the opening does not run through the centre of the key, therefore only 

 one side of the key covers the opening in the barrel, while in tliecom- 

 inon firecock both sides are covered. 



Fig. ".—Double Firo-cock, used at the British Museum. 



Fig. 7 is a double firecock, as Inid down at the British Museum. 

 This has a very good delivery, and is certain to be always tight, if 

 well made, as the pressure of the water forces the key into the barrel; 



