IV NOTES BY THE EDITOR. 



We can point with pride to some substantial engineering work 

 of the past year : notably, the building, launching, and placing 

 the great caisson at the Brooklyn terminus of the East River 

 bridge. An extract from the report of Col. Roebling will be 

 found in the present volume. 



It is stated that the great central shaft of the Hoosac Tunnel 

 has reached the grade of the tunnel 1,030 feet below the natural 

 surface. 



The Broadway Underground Railway is well underway ; the 

 construction progressing while the thoroughfare above is crowded 

 with its endless procession of vehicles. 



The St. Louis bridge, under the able engineering skill of Captain 

 Eads, progresses finely. 



The removal of the obstruction at Hellgate is continued day and 

 night. These and the work of the coast survey testify to the pres- 

 ence of engineering skill among us. 



The European war has not called forth to a large extent the in- 

 ventive capabilities of our population, while it has had distinctly 

 this effect abroad. Activh>, however, among the American manu- 

 facturers of arms and ammunition has necessarily followed. 



As a proof of the esteem in which American weapons are 

 held abroad it is stated that the Remington Co., N. Y., have ex- 

 ported to Denmark 25,000 breech-loaders, and as many to the 

 Swedish government. Colt's Co., 30,000 Berdan rifles to Russia. 

 Turkey has also been a large purchaser. Nearly the half of the 

 work of Smith & Wesson's manufactory is bought by European 

 parties. And the Union Metallic Cartridge Co. send their prod- 

 ucts to all parts of the world. 



We learn, from the "London Broad Arrow," that "12 of the 

 Gatling guns of 45-bore have been ordered from America for the 

 government absolutely, and 50 additional on the understanding 

 that they will be taken. Meanwhile, 50 more of these guns are 

 being manufactured by Sir William Armstrong, at the Elswiek 

 ordnance works, in expectation that they also will be taken by the 

 government. As it is understood to be the intention of the gov- 

 ernment to arm each of the ships of war with a mitrailleuse, in 

 addition to supplying a certain number to the army, it is clear that 

 several hundreds of this arm will be required." 



The new explosives, nitre-glycerine, dualin, lithofracteur, and 

 dynamite have received considerable attention during the past 

 year. Full accounts of dualin will be found in the present volume ; 

 it seems to promise well for certain kinds of work, although the 



