108 Chronicles of Science. [Jan., 



Kailway is now completed at Messrs. Samuda's yard, Poplar. It is 

 230 feet long, 12 feet 9 inches internal diameter, and is formed of 

 f-inch boiler plate, surrounded by four rings of brickwork; its 

 weight as it lies is nearly 1,000 tons, Bulkheads are to be fitted 

 at each end, when it will be floated to its destination above Hunger- 

 ford Bridge. Here an inner ring of brickwork will be built inside 

 it, and it will then be sunk upon its piers, and its ends secured in a 

 junction chamber. 



A pneumatic despatch tube is now being laid down in Paris, 

 from the telegraph office near the Grand Hotel, to that in the Place 

 de la Bourse, and others will shortly connect those with the central 

 telegraphic office on the other side of the river, the head-quarters 

 of the post-office, and other stations. The system adopted in Paris 

 is the reverse of ours. While we exhaust the air in advance, our 

 neighbours' system is to compress it behind the despatch truck, at a 

 pressure of one atmosphere and a half. 



The surveys for the Busso- American telegraph have been com- 

 pleted from Anadyrsk to the Amoor, a distance of 6,000 versts, and 

 the direction of the line has been determined. As soon as the sea 

 of Ohkhotsk shall be free, vessels belonging to the Telegraph Com- 

 pany are expected to arrive at Guigiga from America with the 

 necessary materials for commencing the works immediately. 

 Already between Anadyrsk and Ohkhotsk the works have been 

 commenced with the assistance of the inhabitants of the country, 

 who are engaged in constructing houses and trimming trees to serve 

 as telegraph posts. 



An iron floating dock for Bermuda is now being constructed by 

 Messrs. Campbell, Johnstone, & Co., of North Woolwich. It is to 

 be capable of docking ships of the Bellerophon class when water- 

 logged ; it is fitted with a caisson at each end, and has a double 

 bottom and sides 20 feet apart. Its internal dimensions are — 

 length, 330 feet ; breadth, 84 feet ; and depth, 52 feet. 



The Norfolk Estuary Company have recently completed another 

 embankment of a mile and a half in length, at Walferty, reclaiming 

 another 300 acres of land in the " Wash." This now makes a total 

 of about 500 out of the 32,000 acres to be recovered from the sea. 



The new Ladoga Canal has recently been opened for traffic. The 

 first canal was commenced by Peter the Great, in order to develop 

 the commerce of St Petersburg ; it, however, proved inadequate 

 to its purpose, owing to the defective system of locks. The new 

 canal has no locks, and thus the project of Peter the Great, who 

 intended that the first canal should be constructed without locks, is 

 now realized. 



The new screw pile pier at Brighton was opened on the 6th 

 October last. The entire length of the structure is 1,115 feet ; it 

 is approached from the shore by an abutment 290 feet long and 



