MECHANICS AND USEFUL ARTS. 89 



from January 4th to February 7th, 137 bars^es of merchandise 

 passed from one sea to the other. On February Gth there were 

 at Port Said 4 three-masters and 3 brigs occupied in land- 

 ing large cargoes of coal. The receipts in 18G7 amounted to 

 1,292,822 francs. The first quarters gave 250,000 francs, and the 

 fourth 474,000 francs. The transit continued to be active in Jan-' 

 uary, 1868. 



London Underground Railway. — The engines are of the usual 

 form, but are so arranged that the exhaust may, at will, be turned 

 into the tank instead of the chimney, and that the furnace may at 

 a moment's notice be shut up air-tight. The road is not a contin- 

 uous tunnel, but a series of alternate tunnels and open cuttings. 

 Iq the open cutting the engines are run as on any other road, but 

 as soon as a tunnel is reached, the exhaust is turned into the tank, 

 the fire-box shut tight, and the engine run through by the accu- 

 mulated heat in the furnace and boiler. The cost of this road 

 was about $4,000,000 per mile. — FranJdin Journal. 



SUEZ CANAL. 



The line of the Suez ship canal, as determined by the commis- 

 sion of engineers, runs nearly north and south, from Port Said, on 

 the Mediterranean, to Suez, at the head of the Red Sea, a distance 

 of 100 miles. The width at the water Hue will be 330 feet, with 

 a uniform depth of 26 feet. The alignment is very favorable, 

 there being but 8 curves ; the shortest radius is 6,666 feet, with 

 an angle of 143 degrees. For nearly three-quarters of the dis- 

 tance the canal will be dredged through a line of shallow lakes, 

 some of them containing brackish water, filtered in from the sea, 

 and others being at present dr}^ indicating the locality of former 

 lakes. The intervening strips of land are parts of the great 

 desert, an arid, desolate waste, with nothing to sustain animal or 

 vegetable life. To supply the fresh water necessary for the men 

 and steam engines, an old canal at Gassassine was extended to a 

 point on the line of the ship canal midway between Port Said 

 and Suez ; the length of this fresh-water canal is 30 miles, the 

 width at the water line 66 feet, the depth 6 feet, and the fall 

 about 2 inches per mile ; its direction is nearly east, and it comes 

 in at right angles to the ship canal at a point now called Ismailia. 

 From Ismailia, the water is forced by steam through 2 cast-iron 

 pipes to Port Said, a distance of 50 miles, to the amount of 54,000 

 cubic feet of water per day; these pipes are tapped at such jxirts 

 of the line as may be necessary to supply the men and engines. 

 At a point on the fresh-water canal, 2^ miles above Ismailia, a 

 branch canal takes off the water southward to Suez, 58 miles. In 

 this way drinkable water is furnished from the Nile along the 

 whole route, whereas formerly it had to be brought from Cairo, 

 across the country by railroad, a distance of 90 miles. It is by 

 the last-mentioned canal that water communication has been 

 opened between the two seas, and not through the ship canal 

 proper, as the public have been led to believe. Tiie northern end 



