192 TliAySACTTOXS OF TUE AMERICAN INSTITUTE. 



removal of 800,000,000 tons of water. Each of tliese engines were 

 capable of delivering 200,000,000 gallons of water per day, and 

 when the three engines worked together would discharge a volume 

 six times as great as that which the Croton Aqueduct is capable of 

 delivering. The next largest pumps in the world are those at the 

 United States Dry Dock at Brooklyn (which are sixty-three inches 

 diameter, and ten feet stroke), and capable of delivering 30,000,000 

 gallons of water per day, from a depth nearly three times as great as 

 that of the Harlem Mere. The steam engines next in size to those 

 at Harlem are those of the Bristol and Providence steamers, with 

 cylinders of nine feet two inches diameter, and twelve stroke. A 

 new pumping engine in London and one in Cincinnati have also cyl- 

 inders of this size. One of the greatest of modern discoveries is the 

 process of converting great masses of pig or cast iron into steel, in 

 twenty minutes, without the aid of fuel or furnace, at a cost of half 

 a cent a pound, and developing a heat heretofore unknown or unused 

 in the arts, and a light equal to the combined eifect of all the gas- 

 burners in the city of T^ew York. When it is remembered, that by 

 the ordinary process, it requires several hours to decarbonize cast- 

 iron and render it malleable, and then a fortnight to recharge it with 

 the small quantity of carbon to convert into steel and another smelt- 

 ing, to produce cast-steel, thereby increasing the cost of the product 

 four-fold, you will see the extent of the changes which this discovery 

 is destined to introduce in engineering structures. Steel of more 

 than twice the strength of wrought iron will soon be furnished at 

 almost the same price. Already we have witnessed the commence- 

 ment of this revolution in the substitution of steel for iron rails upon 

 all our leading railways. Apprehensions have been expressed that steel 

 which unusually is considered so brittle, will not withstand the heavy 

 shocks of the locomotives in our severely cold climate. But I can say, 

 from my own experiments and examinations here and abroad, that 

 steel rails, properly made, are really very much tougher and much less 

 liable to break in extreme cold weather than those made of the 

 best of wrought iron. In fact, by this new process the rails are 

 necessarily made of the exact degree of hardness and toughness that 

 is demanded, and the English engineer now prescribes the extent of 

 the carbonization of the iron, with a limit of variation of only one- 

 tenth of one per cent. The tires of locomotives, the axles of cars, the 

 large rods of steam engines, large and small shaftings, and many other 

 of the most important parts of machinery are now. made of this metal, 



