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Illustrated articles on topics of timely interest are solicited for publication. Those that are short and accompanied with good photographs will receive special attention. Accepted articles will be paid for at regular space rates.
"LSEWHERE in this issue will be
found an interesting description of the remodeling of the Grand Central terminal in New York City, which, when completed according to the plans outlined, will undoubtedly be one of the most important and best equipped of railroad terminals ever built. It is also of interest to note that in connection with this great engineering work electricity is to be one of the most important factors. Electric locomotives will be used exclusively for the operation of all suburban trains, and for a distance of 34 miles on the main line of the New York Central & Hudson River Railroad and 24 miles on the Harlem division of this road.
The fact that trains have hitherto entered New York City through a long tunnel, is one of the strongest arguments for the use of electrical propulsion, as there is to-day a growing feeling among engineers that electric power is the only safe power to use in tunnels or subways. Where ventilation is not very
Q You will never find time for anythingif you want time, you must make it.
C Take pride in the hard, consistent, straightforward, and uncompromising effort which has been stamped as “the strenuous life.”
C. You cannot prevent the birds of the air from Aying over your head, but you can prevent them from building their nests in your hair.
thorough, the fumes from steam loco- Growing Use of Steam motives endanger the lives of passengers,
Turbines while escaping steam has caused serious accidents by obscuring signals.
Two years ago the steam turbine was The first of the new electric locomo hardly considered in connection with tives built for this service was given an large power plants, although this was official trial a few weeks ago. It has one of the earliest suggested forms of four driving axles, each of which car steam engines. Turbines of the Parsons ries the armature of an electric motor type, having an extremely high velocity mounted directly upon it; and the motors of rotation, and using gearing to reduce have a normal rating of 550 horse-power. this to practicable speeds, have been in This makes the total rated capacity of use for some time to a limited extent, for the locomotive 2,200 horse-power, al special applications; but, within a comthough for short periods it is capable of paratively few months, turbines having developing considerably greater power several stages and operating at comparthan this. It is of interest to note that atively low speeds have been perfected this is more powerful than the largest and introduced to such an extent that steam locomotive in existence.
they have already brought about considThe heaviest trains which are to be erable modification in the design and arhandled by electric locomotives weigh rangement of steam plants. 875 tons, and are drawn at a maximum One of the most noticeable features speed of from 60 to 65 miles per hour.
in turbine plant is the relative For hauling these heaviest trains, two size of the turbines and reciprolocomotives are coupled together; and, cating engines of the same capacity. when so coupled, the method of electrical The floor space occupied by a large crosscontrol is such that they can be operated compound engine would be sufficient for by a single crew from either loco three or four times its capacity in turmotive, only one controller being used to bines, and this saving in space means actuate all the motors on both locomo considerable in the case of plants located tives.
at cities where real estate is very valuOn the trial trip a maximum speed able. of 63 miles per hour was attained with Another modification due to turbines an eight-car train; and with a four-car is the very noticeable increase in the prestrain, 72 miles per hour was reached. sure and temperature of the steam. From Both of the trains were still accelerating 150 to 200 pounds' pressure, and from at these speeds, but the length of the 100 to 200 degrees of superheat, are fretrack electrically equipped did not per- quently used in connection with steam init of reaching higher speeds.
turbines ; and much higher vacua are also The electrical system which is being generally employed, as the economy of adopted by the New York Central is, high vacua is more marked in the case however, applicable only for terminal pur of the turbine than in that of the recipposes or over limited distances, as the low rocating engine. The efficiency of the voltage of the current used entails a cost steam turbine is somewhat higher than for electrical conductors and sub-stations the average efficiency of steam engines, along the line of the road which would although a multiple-expansion reciprocatbe prohibitive if extended over great dis- ing engine oi European make has been tances. But the fact of electricity being tested under high vacuum and extremely used in such heavy and severe service is high superheat, which showed a higher no small triumph of electrical engineer- efficiency than the turbine has yet ing; and it is not improbable that the reached. Where average working conexperience of steam railroad men with ditions are found, however, the turbine this flexible, powerful, and cleanly mo undoubtedly has some advantage in the tive power may pave the way for the matter of efficiency. adoption of high-tension alternating cur Aside from high efficiency, the turbine rent systems which will be able to op has many points to recommend it, among erate economically over very long dis which may be mentioned the absence of tances,
reciprocating parts, the absolute uni
formity of iurning moment throughout chines, in which case inter-coolers are an entire revolution, the ease and sim generally used between the different plicity of repair, the absence of all bear stages of compression, which cause the ing surfaces, except the two main jour- air to shrink in volume between the nals, and immunity from accident by rea stages. A properly designed inter-cooler son of water being carried over with the should reduce the air in the cylinders to steam. Its overload capacity is also very the temperature of the outside air. The large, and its economy under varying economy of compressing in several loads very marked. These points of ad stages-or, in other words, compound vantage have been sufficient within a very compressors—is shown from the fact that short time to make the steam turbine a in compressing air up to 100 lbs. the formidable rival of the highest grades heat loss reaches about 30 per cent.
By of reciprocating engines on the market. compressing in two stages, this loss is
cut down to less than half; and in four
stages, it is reduced to four or five per Compressed Air
cent. It is evident, therefore, that the
higher the pressure required the more esTHE HE vast number of applications of sential is the use of compound machines.
compressed air to modern engineer. It is probable that much of the delay in ing problems have proved it to be one of the adoption of compressed air for nuthe most flexible and efficient agents for merous purposes has been caused by the the transmission of power over coni complicated and ponderous machinery paratively short distances; and when its formerly used; but this objection is rapadvantages come to be more generally idly disappearing with the introduction appreciated, its use will be extended to of simple, durable machinery which can many of the operations of everyday life. be readily operated by entirely unskilled In view of its rapidly growing field of attendants. usefulness, the description of various forms of air-compressors, which will be found elsewhere in these pages, is of
Training Sailors timely interest. Owing to the wide vari
Technically ations of air pressure required for different services--which range from a few THE old-time able seaman had to know ounces' to several hundred pounds' press how to “hand, reef, and steer.” ure per square inch-a number of differ- Such, nominally, is the requirement of the ent types of compressors have been de- able seaman of the navy of to-day, though veloped. With the fan and blower types, in practice he has neither to hand nor reef. whose limits of economical operation are and the ship steers by a mechanical gear within one pound pressure, few difficul which responds to the touch of a finger ties are found in the construction of the even in the heaviest seas. The sailor who compressing machinery, which is ex would rise above the ordinary to-day, tremely simple.
must have technical training. Seamen for As the pressures increase, however, our increasing Navy are none too plentithe machines become
and more ful, and those who come to it with techcomplicated, owing not only to the great nical training are few indeed; so the er power required, but also to the heat Government is taking the matter in hand ing of the air during compression. The and giving it to them after they arrive. dissipation of heat, is in fact, one of the The United States Navy is establishing most difficult problems with which the the most thorough system of wireless designer of air-compressors has to con communication in the world, and to optend. The use of water-jackets for cool erate this it must have many wireless ing the air in the compression cylinders operators. At present a corps of twentyis general, but this does not effect thor five sailors is being trained in these mysough cooling, as only a small portion of teries at the Brooklyn Navy Yard. It the air in the cylinder comes in contact takes three months to make a wireless with the jacketed parts. This difficulty operator out of the average sailor from has led to the use of compound ma the warships; and as soon as he is made,
he is turned over to one of the various a lesson was learned from this prodigalstations far or near, to begin active serv ity, and the safeguarding of the much ice at a salary increasing as he shows reduced supply began. During the last efficiency and is promoted. The ordinary few years new wells have been struck, seamen recruits receive but $16 per and, the lesson having been learned, the month, but the wireless man when gradu- industry seems to be once more on a ated is rated as a third-class electrician prosperous basis. The supply is virtually at $30 per month. From that, advance confined to four States-- Pennsylvania, ment brings rapid increase up to the po West Virginia, Indiana, and Ohio. Last sition of Chief Electrician at $70 per year's output from these States was the month. The Bureau of Equipment is most valuable since the first wells were preparing to establish a network of wire sunk. In round figures it represented less stations covering the entire coast of nearly $30,000,000. The volume at atthe United States from Key West in Flor- mospheric pressure was 238,769,067,000 ida to Alaska and the Aleutian Islands in cubic feet, and its heating value was estithe north, and extending to Honolulu,
Honolulu, mated as equal to that of 11,938,453 tons The Philippines and the Panama Canal of bituminous coal. strip. When you add to this the fact that every warship in our great and growing Navy is equipped with similar apparatus Valuable Invention and must hence carry two or more op
Lost? erators, it will be seen that the chance for electrically trained young men in the THE fact that lead men tell no Navy is a good one. The modern bat tales” has lately caused much untleship is no longer a fine sailing ship casiness in the scientific world, for two equipped with guns, but a huge and com men who recently died are feared to have plicated floating mechanism requiring taken with them a secret of great imscores of highly trained men to make her portance. In certain classes of efficient. In this fact lies the hope of ad scopic work, a concave mirror is used vancement for the man who enters the on which are engraved parallel lines, service already equipped with a good me sometimes 100,000 to the inch. Profeschanical training
sor Rowland of Johns Hopkins University, a scientist of splendid mechanical
ability, invented a machine for making Natural Gas Again these lines. Its principal mechanism NA (ATURAL gas, not such as bubbles was a screw with an exceedingly fine from political orators, but the kind
thread that had to be cut and ground which flows from the depths of the earth,
under water by a method hitherto unis again coming into constant and in known, which the professor taught only creasing use, because the supply is once to his head mechanic. These two men more to be depended on. When this alone held this priceless secret for years, great source of light, heat, and power
and ground out the machines regularly from the chasis of the earth was first for the whole world, but did not grind discovered, it was used with reckless ex
out the secret with them. Then one day travagance. The cities and towns near Schneider, the head machinist, died. the wells received it at merely nominal Professor Rowland at once set to work rates, and acted as if they knew the sup teaching the secret to another foreman ; ply was exhaustless.
but before it was accomplished, Rowlighted by it at night, and it was burnt land himself died. in countless ways for the fun of the Is the secret lost? It remains to be thing. Great industries were built up seen. Attempts have lately been made dependent on its use; and when the sup to cut a new screw like those cut by ply, as might have been expected, began Schneider and Professor Rowland, and to decline, suffered from the lack of it. the scientific world is waiting the result The supply ran low and lower, and gas with great interest. If it fails, the three was regarded as a declining product, machines already in working order will likely to pass away almost entirely. But be priceless.
On this rock, tradition tells us, the Pilgrims from the “Mayflower” landed, December 21, 1620. Although its reclining place is in the little Massachusetts town whose name it bears, Plymouth Rock underlies all America. On it Putnam stood when at Bunker Hill he shouted, “Don't fire till you see the ites of their eyes;" and Jefferson had it for a writing-desk when he drafted the Declaration of Independence.