1869,] Engineering — Civil and Mechanical. 113 



of tlie harbour. This will form part of a system of defensive works 

 for the protection of Bombay Harbour, which was determined on 

 some years back. Several of the minor works, comprehended in the 

 defensive system, have already been completed, 



A firm of gas engineers and contractors in New York have 

 recently undertaken the erection of gas works at Canton, in China. 

 The main building for retorts, &c., will be 184 feet long, made of 

 iron, and manufactured after the most approved plans. The works 

 will have a capacity to make 500,000 cubic feet per twenty-four 

 hours. All the materials for the buildings, gasholder, and works 

 will be made, fitted, and shipped complete, ready to be put up im- 

 mediately on their arrival at their destination. 



On 24th November the new Smithfield Meat Market in London 

 was opened to the pubhc with some ceremony, by the Lord Mayor 

 and Civic Corporation. The market is a parallelogram, 631 feet in 

 length by 246 feet in width, and covers ?>\ acres. The general 

 height of the external wall is 32 feet. There are 162 shops in the 

 market, each about 36 feet by 15 feet; and behind every shop is an 

 enclosed counting-house, with domestic apartments overhead. The 

 lower part is filled in with broad glass louvres, so placed that while 

 air is admitted freely the direct rays of the sun are kept out. 



Mechanical. — Peet's stop-valve, which forms an admirable substi- 

 tute for all other taps, stop-cocks, or stop-valves, is now being largely 

 manufactured by Messrs. Josej)h Whitley and Co., of the Kailway 

 Brass Works, Leeds. This valve has the advantage of giving an 

 unobstructed line of communication when open, and when shut it 

 comprises two steam-tight surfaces. The opposite internal sides of 

 the valve are parallel, and instead of a single wedge-block, two 

 separate discs are employed, which go down loosely to their bearing, 

 when they are forced apart and driven close home by a conical end 

 to the spindle. Thus, in the event of any obstruction preventing 

 the proper closing of one of the discs, it in no way interferes with 

 the other disc taking a perfect bearing. 



A new method of applying steam to the propulsion of canal 

 boats has been tested on the Erie canal. The driving-wheel is 

 placed in the middle of the boat, and rolls on the bottom of the 

 canal, being so arranged as to rise and fall with the irregularities of 

 the bottom. The speed thus obtained is from two to two-and-a-half 

 miles per hour. 



A very useful invention has recently been patented by Mr, An- 

 drew Murray, of H.M.'s Portsmouth Dockyard, designed for the 

 purpose of hauling stranded vessels into deep water, in attempting 

 to do which ordinary steam-tugs generally fail completely. The 

 invention consists in fitting one or more powerful capstans on board 

 a vessel which is to be placed between the stranded ship and one or 

 more heavy anchors, laid out in the direction in which it is desired 



VOL. VI. I 



