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for its terminus. The old project of the North Atlantic is being again mooted. That route was to go by Iceland, Greenland, and so on to Canada and the United States, Denmark being the assumed starting-point. The cable to India by the Red Sea is going on satisfactorily, and an auxiliary line, one between Marseilles and Malta, is spoken of.
All these projects indicate increased convenience and gain to the public. At present the use of the ocean telegraph is confined to the commercial community; but ere long, when the tariff is reduced from Europe to America, and to India, the general public will send messages as freely as they do by the land wires. We may reasonably hope, too, that the cost of submarine cables will be reduced by and by, and this will do more to cheapen messages than anything else.
In Northern Russia the construction of a land line is far advanced to connect St. Petersburg with the mouth of the Amour River, on completion of which only a submarine link will be wanting to complete the telegraphic girdle round the earth.
Electricity and steam are the great agents of civilization. The introduction of telegraphic lines and railways in Russia and Asia is destined to revolutionize this part of the globe. We Americans are apt to think ourselves the most progressive nation, and point with especial pride to our Pacific Railway. Russia, however, is making great strides; and the English railways in India compete in difficulty of execution and magnitude with the Pacific Railway.
During the past year several improvements in railway carriages have been brought before the public.
Mr. Robert F. Fairlie has invented a steam carriage which will round curves of 50 feet radius at 20 miles an hour, with, it is alleged, perfect safety. The carriage, instead of seating the usual complement of 100 passengers (English car), seats only 66. The English papers are enthusiastic in regard to this carriage.
The Portmadoc and Festiniog Railway, in Wales, has also attracted much attention, from the narrowness of its gauge, – two feet only. The Fairlie carriage and the narrow-gauge railway will undoubtedly come into play in difficult countries.
We are certainly far from perfection in the construction of our railways in America. The fearful catastrophes that have taken place from cars taking fire have reawakened an interest in new methods of heating them. No method has yet been devised to meet the difficulty satisfactorily. In this volume will be found the description of an electro-heating apparatus. The introduction of steel rails promises to make accidents from defective rails rarer.
The English have lately turned their attention to the American system of constructing railroads. They have found, to their surprise, that in India they must adopt American ideas. Notwithstanding its defects, it has been found that our system is likely to prove the best for their colonies. A commission of English engineers are now investigating our system with a view to the railways of India.
The brake power on several of the French and Spanish railways has been greatly increased by an ingenious arrangement conceived by Monsieur Chatelier, of applying what has been termed “contre vapeur" to the engine, converting it, for the time being, into a pump forcing steam and water into the boiler.
At a meeting of the American Academy of Arts and Sciences, held in Boston, U. S., the Rumford medals were presented to Mr. George H. Corliss, of Providence, R. I., for his improvements in the steam-engine. The presentation was made by Dr. Asa Gray, the President of the Academy. We make the following extract from his remarks:
“It appears that within the twenty years since this machinery was perfected, more than 1,000 engines of the kind have been built in the United States, and several hundred in other countries, giving an aggregate of not less than 250,000 horse-power; that as to economy of fuel, evidence has been afforded to the Rumford Committee, showing a saving over older forms of engines of about one-third. As to its other crowning excellence,'uniformity of velocity, the purchasers of one of the engines, now in its eighteenth year of service, certify that, with the power varying from 60 to 360 horse-power within a minute, the speed of the engine is not perceptibly affected.”
While we chronicle the great works in engineering, the improvements of the past year in making steel promise still greater achievements. The Bessemer process has already done much; the later discovery of Bessemer, the high-pressure furnace, by which the melting of ores is accomplished much more speedily and economically than by the old processes, is destined, it is thought, to further cheapen steel. It is stated that Bessemer was led to this discovery by meditation on the cause of the heat of the sun, and the influence that the force of gravity, 27 times greater than that upon our earth, must have upon the intensity of that heat.
The Siemens regenerating furnaces are being rapidly introduced into this country.
These processes tend towards cheapening a very first-class material, which will undoubtedly supersede iron for almost all structural purposes. Engineers hesitate at present to use this material, since no adequate experiments have been made in regard to the limits to which steel structures can be loaded with safety. Experimental researches have been carried on for some time in England, at Woolwich, under a committee appointed by the Institution of Civil Engineers, which promise to supply this want.
The results of Mr. Whitworth's experiments, tending to supersede the hammer and rolls by forcing cast steel, while in a semifluid state, into strong iron moulds by hydraulic pressure, are regarded with great interest.
The use of pulverized fuel, experiments on which are now being conducted, promises, by surrounding each particle with just the amount of oxygen which it needs for perfect combustion, to utilize fuel to greater advantage.
" The Bulletin of the American Iron and Steel Association" states that 65 new blast furnaces have been erected in this country during the last 18 months. It adds that it has a record of 58 more in contemplation, the greater number at the West, nearly all of which will be built the coming year, if those engaged can be assured of the stability of the tariff.
The “ Bulletin” computes the total product of Pig Iron in this country during 1869 at more than 1,900,000 tons. In 1865 (the first year after the war), it was but 931,000 tons, an increase without a parallel in the history of any country.
Steel rails are being largely adopted both at home and abroad. The results of the experiments-made are not merely satisfactory in regard to the increased durability of the new material. They demonstrate that the section might be materially reduced. The Northern Railway Company, of Austria, was one of the earliest to experiment upon rails of Bessemer steel, and exhibited specimens of its rails at the exposition of 1867. With a weight per yard of only 45 pounds, the company obtained a steel rail having double the strength of the iron rails of a larger section previously employed by them; the cost to the company per ton of iron rails having been from 60 dollars to 70 dollars, and that of steel rails being from 90 dollars to 100 dollars. The expense per running mile is still kept nearly within its original limits, with a very great improvement in regard to strength and durability.
The French Railway Companies are also extensively introducing rails of Bessemer steel upon their roads. These rails, as manufactured at the principal French works, cost from 60 to 70 dollars per ton.
There is a growing feeling among engineers and steel makers, that the compound rail, made wholly or partly of steel, will prove more safe and economical than any solid rail, for, if the same durability of track can be obtained with a steel cap as with an all-steel rail, the first cost will be greatly decreased. A rail made in two or three continuous parts, breaking joints, is also a practical insurance against disaster from broken rails.
It is estimated that in the United States from 40,000 to 50,000 tons of steel rails are in use on our various railways.
The Lehigh and Susquehannah is entirely built of steel. Other railways are using them largely, the Hudson River, Erie, and Pennsylvania Railways using 10,000 tons or more each. The last report of the New Jersey Railway and Transportation Company says: “It is probable that steel rails will be gradually laid the entire length of the road, the greater durability of these rails overcoming the objection to their increased cost."
The use of steel rails will guarantee greater safety of life and limb, and their introduction, therefore, should be hailed with delight, for the term American rails has become a synonym for the cheapest and least durable rails manufactured.
Our late war taught us much in regard to ordnance and iron ships. The great advances in the manufacture of steel, and the discovery of new explosives, are destined to materially further our knowledge.
The most noteworthy improvement of this year in fortifications is Captain Moncrief's system. By an ingenious device he lowers his gun upon its rocking carriage after firing, and thereby does away with embrasures (the weak places in protecting works), while he gains the advantage of reloading his gun in comparative of safety.
What influence the new explosives, picrates, dynamite, and ammonia powder will have on warlike operations, remains to be
Attention has lately been turned to gas as a calorific agent. Profs. Silliman and Wurtz, by their researches, promise to increase our knowledge of its illuminating power.
Articles will be found on page 90 bearing upon this subject.
Prof. Tyndall says that the superiority of gas for light-houses over oil is rendered very manifest by the experiments lately instituted at Howth Baily and Wicklow Head.
One cannot fail to notice the impulse which the completion of the Pacific Railway, the Suez Canal, and the French Atlantic Cable have given to the desire implanted in the human breast to overcome natural obstacles. M. Lesseps advocates flooding the desert of Sahara by means of a canal, and thus afford communication with the interior of Africa.
Among the projects that have been re-agitated the past year, are the project of a canal around the Falls of Niagara; a re-enlargement of the Erie for vessels of 1,000 tons; one across the Alleghanies in Virginia; one through the Isthmus of Darien, the expedition for surveying which has already started, and one from Huron to Ontario. In tunnels we have that of Mt. Cenis, 8 miles, and the Hoosac, 5 miles, in length, both in rapid progress; one of wrought-iron tubes at London, and another at Chicago; tunnels proposed under the East and North Rivers at New York; under the Ganges at Calcutta, and under the Straits of Dover.
In view of past achievements, it is not safe to pronounce any of these projects not feasible.
In physical science, Tyndall commenced the year with a picturesque account of a discovery of the peculiar action of light upon vapors.
In electricity we have no startling discoveries to chronicle. M. Jamin, it is said, has ascertained that magnetism can be condensed for a short period in the same way as electricity. Prof. LeRoy Cooley, of Albany, has discovered a way of registering vibrations by means of electricity. His method will be found on page 162.
He dispenses with the sirene, and obtains a direct registration, the vibrating body itself opening and closing a circuit.
We have about the usual number of new batteries to chronicle. The combination of elements to produce currents seems unlimited.
The energies, however, of most of our physicists, both at home and abroad, have been directed to the field of spectrum analysis.