FIGS. 5 AND 6.-NEW FORT WAYNE CUT-OUT AND ARC SWITCHBOARD.

During the test of the machine the potential at the terminals was measured by means of two Weston voltmeters, specially designed for the purpose.

FIGS. 3 AND 4.-CIRCUIT OF NEW WOOD MACHINE: AND DIAGRAM OF DIRECT COUPLED UNIT.

wrought-iron forgings, joined by a heavy cast-iron yoke at the top and provided with cast-iron pole pieces. The entire regulating mechanism is placed within the pillow block and is operated by a small round belt from a pulley at the end of the armature shaft. The regulation of the machine is effected after the manner of the Wood system, now well known and long tried. Sparking is almost entirely avoided by varying the distance i. e. the number of commutator segments between the two positive and the two negative brushes. The regulation is such that fifty lamps and more can be switched in or out without fear of endangering the machine. It is, indeed, remarkable that an efficiency exceeding 90% should be secured in an arc machine, as it is in this.

The circuits of the machine and its connections are shown in Fig. 3. From these it will be evident, as stated above, that the machine is entirely self-contained. The wires leading to the circuits are taken from the binding posts at the base of the machine and carried below the floor to the switchboard, thence through the lightning arresters and to the outside circuits. This leaves the dynamo room entirely free from the wires which usually connect with such a machine from overhead; and thus gives the whole a substantial and neat appearance.

The engraving, Fig. 4, shows the new Wood machine coupled direct to a Willans high-speed engine. This

combination was got up to meet the specifications of the Detroit municipal electric light plant.

Among the new auxiliary apparatus manufactured by the Fort Wayne Company is the arc switchboard shown in Fig. 5. The plug sockets are mounted on marble bases, the line terminals above and the dynamo terminals on the lower board, with the voltmeter and ammeter and ground connections on the central panel. This board embodies the ingenious devices of Mr. Wood, by which a circuit can be changed from one machine to the other without causing a break in the circuit.

to

bulb at its further end. On current passing through this heating coil the air in this bulb is expanded and forces part of the liquid in the tube to overflow into the trap bulb, where it remains until reset. When the current is cuto ff, the air in the heating bulb naturally contracts, and the liquid in the tube therefore recedes, leaving a part proportional to the maximum current that has passed in the trap bulb, and displaying in the tube against the scale a shortened column of liquid similar to a thermometer. It will be seen that the lower the column of black liquid in the glass stem, the greater must be the number of full-price units consumed before the 50 per cent. rebate commences. The heat developed is, of course, proportional to the square of the current, but, owing the cushioning due to the air in the receiver bulb, the volume of liquid spilled is practically proportional to the first power of the current. Great care is taken to calibrate every indicator, but the scales are almost exactly, if not quite uniform. The instruments are reset very easily, all that is necessary being to tilt the interior part, which is hinged for the purpose, until the liquid in the trap bulb flows back and refills the tube. The loss of pressure does not exceed half a volt even in the smallest instruments, and is quite inappreciable in the larger ones. The influence of this demand indicator upon the habits of the consumer is most salutary. Instead of burning a great many lamps at a time for short periods, he is induced to burn a normal number of lamps for long periods; thereby unconsciously flattening the station load diagram and filling out the work of the plant over an extended period. The engineer of the Brighton station reports that the influence of this indicator has been most marked, and that the station load factor is now 15 per cent. better than during last year.

A PRACTICAL TEST OF MATHER APPARATUS IN PHILADELPHIA.

The Mather Electric Company, of Manchester, Conn., has issued a small and convenient catalogue from the press of Bartlett & Co., giving a short description of the improved, ring type dynamo with the dimensions of the different sizes manufactured by the company, together with a partial list of plants now in operation.

Among these plants may be especially mentioned the equipment of the Pennsylvania Institute for Deaf and Dumb, in Philadelphia, where there are installed four 550-light ring type dynamos, driven by four 60 h. p. New York Safety engines. These have all been in use for a year and a half, during which they have

66

FIGS. 1 AND 2.-WRIGHT'S DEMAND INDICATOR.

demand indicator," the object of which is to furnish a correct means of ascertaining the actual call each consumer makes upon the generating plant of the central station.

In order to understand the duty of this instrument it is necessary to describe the system of charging adopted by the Brighton Corporation, which is as follows: 7d. per unit (1,000 watt hours) is charged until the quantity consumed amounts to a use of the average maximum demand for 365 hours in half a year, which equals two hours per day, and all current consumed in excess of this quantity is charged at 3d. per unit. The average maximum demand of each consumer is directly shown by the demand indicator being read once a month and the mean being taken as the consumer's actual demand. The Brighton instruments are calibrated to show directly the number of units to be consumed in the half-year before half price is charged instead of in amperes, as, at the Brighton voltage, each ampere used for two hours per day equals 42 units in the half-year. On this system the consumer is allowed a rebate directly his own load factor exceeds 8% per cent.

But the consumer is allowed to have a blaze of light occasionally, without fear of being betrayed by the faithful indicator. In order to prevent any single special demand for electricity raising the number of full-price units, the consumer may, in the event of his intending to burn a number of lamps in excess of his usual maximum on any such occasion not exceeding once in each month, give 24 hours' notice, in writing, of such intention to the Corporation, and they will thereupon short circuit the consumer's "demand-indicator" from registering the demand on the occasion so notified.

Two views of this indicator are seen in the accompanying engravings; Fig. 1 shows the front exterior of the instrument, as it is placed in the consumer's house, and Fig. 2 shows the interior arrangements of the latest pattern. The current passes through a heating resistance coil which surrounds a sealed glass bulb, connected to which is a U-shaped tube filled with liquid, with a trap

MATHER PLANT IN THE PENNSYLVANIA INSTITUTE FOR DEAF AND DUMB.

run without a single hitch. The switchboard is furnished with Mather instruments exclusively, with the exception of a Weston station voltmeter. A special building has been provided for the plant, which is now operating between 2,000 and 3,000 lights, with room for more when needed.

The work of installation was done by Chas. S. Solomon & Co., of Philadelphia.

CENTRAL ASIAN TELEGRAPHS.

A young Chinese engineer Woo Hown Yung, who was educated at the Hopkins Grammar School, New Haven, Conn., has erected, it is said, a telegraph line crossing about 3,000 miles of Central Asia, starting from Tientsin. Branch lines are now in course of erection to connect with the Russian network.

AN ELECTRICAL CANAL BOAT IN FRANCE.

IN THE ELECTRICAL ENGINEER of April 11, 1894, an account was given of the use of an electrical canal boat on the Canal de Bourgogne, France. The boat is now illustrated. Water power is utilized for the generation of the current, which, by means of a double overhead trolley line is carried to an electric motor on the

TROLLEY CANAL BOAT ON THE CANAL DE BOURGOGNE.

boat. This motor drives a drum over whose teeth pass the links of a submerged chain, by hauling upon which the boat makes its advance slowly. The chain is shown in the drawing, at the head and stern of the boat. In this instance the motor takes the place of the ordinary steam engine, in driving the haulage drum. In the de Bovet system, which has been noted in these columns, the drum is made magnetic in order to obtain greater hauling effort. It may be noted that in the installation upon the Canal de Bourgogne, the generating plant charges accumulators during the night, the current from which is utilized during the day. The use of the motor is said to be found economical, while less attendance is necessary, and the absence of the heat, etc., encountered in the use of steam, makes the newer method far preferable. Part of the current from the generating plant is also used to light a tunnel through which the barges pass.

THE BARMEN ELECTRIC RACK RAILWAY.

The cities of Barmen and Elberfeld occupy a prominent position as German industrial centres; and they also have claims to natural charms almost equally famous in North Germany. Surrounded by forest-clad hills and bighlands, they possess in these admirable breathing places the means of recreation for the city workers. For a long period however, the difficult access to the neighboring hills has proved a great obstacle to any extensive enjoyment of natural beauties; and wishes have continually been expressed for some method of transit by means of which there might be obtained sufficient accommodation for the heavy passenger traffic

SECTIONS OF TRACK ON BARMEN ELECTRIC RACK RAILWAY.

from Barmen to its southern suburbs, where there are magnificent parks and forest land, giving splendid views of the Wupper valley.

The plans submitted by Siemens & Halske for the operation of a rack railroad by means of electricity were, after due consideration, accepted by the Barmen Mountain Railway Co.

The line begins in the centre of the town in a large terminal

station building which fronts upon the Clepsstrasse. The total length of rack line is as near as possible one mile, in which distance it rises about 550 ft. The mean grade is therefore, in round numbers, 1 in 10, the steepest grade on the line being, 1 in 5.4 and 1 in 7.2. The sharpest curve, where the line crosses into the Luisenstrasse, has a radius of 500 ft. Besides the two termini there are also two intermediate stations or stopping-placesone on the Lichtenplatzerstrasse, and another near the Kohlenstrasse. The line is double track throughout, and is of metre gauge. Between each pair of rails is fixed a rack rail of the Riggenbach pattern, with teeth about 31⁄2 inches long, pitched 3 inches apart. Each section of rack rail is about 10 ft. long. The adhesion rails are in general of the ordinary flatbottomed type, though Phoenix girder rails (with grooves as used on street tramways) are employed for the sections along or across the streets. Both rack and adhesion rails are fastened to iron cross sleepers, spaced 40 inches apart. To prevent the rails-both adhesion and rack-from slipping downwards, they are firmly secured for their entire length to footplates bolted to the sleepers; whilst at intervals of 50 or 60 yards two adjacent sleepers are firmly anchored to strong concrete foundations sunk deep into the earth. The adhesion rails average 30 ft. in length.

At the terminal stations there are provided cross transfer tables, worked by electric motors, which move the cars-as they arrive from one line to the other; all shunting is thereby avoided and a great amount of time and trouble saved, as the tables operate automically.

The rolling stock is designed solely for passenger traffic, each car having accommodation for 28 persons seated, with standing

places for six or eight more. They measure in length 26 ft., and are divided into four compartments, of which the inner two are entered from the side as with ordinary railway carriages, whilst the outer ones are approached from the end platforms. Each car has two axles, carrying toothed wheels, which gear into the line rack, and are revolved by means of two separate electric motors, with a capacity of 36 H. P. each. Besides the regular hand and automatic brakes the braking action of the armature is employed in descending, which converts the motor into a generator, and hence sends current into the line.

The cars are lighted, of course, by means of incandescent lamps, fed with current from the main conductor. The latter is placed overhead, along the centre line of each pair of rails; it is of solid drawn copper, and hangs at a height of about 16 ft. above the ground level from insulators, on cross wires, which span the track at regular intervals of 100 ft. or so. Along the city streets these span wires are stretched across from insulators on the top of ornamental steel tubular poles; but outside the town, and along the line, where fenced in, wooden poles are employed for the purpose. Traveling contact between the conductor wires and the motors on the cars is maintained by means of two oblong metal frames, the top sides of which bear against the under side of the conductor. The frames themselves are supported by tubular uprights hinged to the car roof, and so arranged with strong spiral springs that the frames at the top come, as stated, into contact with the conductor wire. The return circuit is completed through the rails to the supply station, strong copper

bonds of large section being employed to connect the rail ends together electrically.

The supply station where the necessary electric current is generated for the line is situated in the Barmen town terminus, underneath the platforms and rails. Two horizontal compound condensing steam engines, running at 165 revolutions, are employed for driving the generators, each engine indicating 250 h. p. They are coupled direct to two ring dynamos with interior field magnet system, generating current at a potential of 500 volts. The total capacity of the station is such as to allow of erecting two more generating sets and two more boilers, similar to those now in use; and these will probably soon be required, for the station not only supplies current for the mountain railway but also for private purposes in the town for electric lighting, small motors, etc. Besides this, it will provide electric energy for a omplete system of street tramways in the town.-The Railway World.

THE PATTON SYSTEM OF STREET CAR PROPULSION.

AMONG the many attempts that are being made from time to time to introduce a system of street car propulsion intended to supersede the overhead trolley construction, the Patton system is one of the latest claimants for recognition. It consists essentially of a combination of gas engine, electric generator, storage battery and motor, all carried on one car. The arrangement is shown diagrammatically in the accompanying figure.

The chief point of merit claimed consists in the employment of a storage battery so arranged as to be capable of being charged

R

E

C

M

DIAGRAM OF CIRCUIT IN PATTON SYSTEM.

continually by the generator, which from the intermittent character of the load can be of considerably less capacity than would be required were the power of the engine to be applied to the car axle direct. In the diagram, E represents a vertical gas engine, coupled direct to the shunt-wound dynamo &; a battery of accumulators is shown at B, and the motor is represented at M. The controller is shown at C, and R is the starting rheostat.

A car equipped with a combination of this kind has been in operation on the Calumet Electric Railway lines at 67th street in Chicago for several weeks and is reported as giving general satisfaction. The operating expense is said to be about one-half that of running a trolley car of the same capacity.

BROOKLYN TROLLEYS TO CARRY THE MAIL.

The Atlantic Avenue Railroad Company has made a contract with Postmaster Sullivan in Brooklyn for carrying the mails from the mail office to the Union station at Fifth Avenue and Thirtysixth street. From this point the mail will be transferred to a special closed trolley car, painted white, and marked "U. S. Mail," for distribution along the line of the road from the station to Coney Island. The company is also considering the proposition of putting mail boxes on all the trolley cars for the convenience of the passengers.

ESTIMATED COST OF SUBSTITUTING ELECTRICITY FOR CABLE ON THE BROOKLYN BRIDGE.

The trustees of the Brooklyn and New York Bridge now have under consideration the use of electricity for lighting and propelling the Bridge cars. The Bridge itself has been lighted by electricity for many years. The subjoined figures were submitted, it is said, by the General Electric Co. in 1892, but the items of apparatus would now be much lower than then :

Estimate of cost and operating expenses of electrical equipment for the New York and Brooklyn Bridge, dispensing with both cable and steam locomotives, and utilizing present steam plant :

First, on basis of present car mileage of 1,269,597 car miles per year. Power required, twelve trains maximum service, five shifting, seven running, of which four are ascending and three descending-five shifting will require a maximum of 1,000 H. P., four ascending will require a maximum of 1,000, three descending will require no horse-power. Total running plant required 2,000 Reserve 1,000 H. P.

H. P.

Horse-power hours per round trip: Each train takes an average of 200 1. H. P. for nine minutes during each round trip, or 30 1. H. P. hours; 420 trips per day will require I. H. P. hours per day, 12,600, or per year, 4,616,700.

Power Plant: 2,000 I. H. P. active, 1,000 reserve; cost of dynamos at $25 per I. H. P. installed, $7,500; cost of line, $6,000; cost of motors for fifteen trains, at $10,000 per train, $150,000; total investment, $231,000.

Operating expenses of motive power: Power plant-fuel, per 4,616,700 I. H. P. hours at four pounds per I. H. P. hour, 8,244 tons at $2.50 per ton, $20,610; water, $2,610; oil and waste, $2,610.

Wages: One superintendent and electrician, $2,500; three engineers, $3,600; three assistants, $3,000; four firemen, $3,000; interest, 5 per cent. on $75,000, $3,750; maintenance, 4 per cent. on $75,000, $3,000; total, $44,680.

Line Expenses: Interest 5 per cent. on $6,000, $300; maintenance, 4 per cent. on $6,000, $240; total, $540.

Motor Expenses: Interest, 5 per cent. on $150,000, $7,500; maintenance, 8 per cent. on $150,000, $12,000; total, $19,500.

Recapitulation: Expense power plant, $44,680; expense on line, $540; expense on motors, $19,500; total motive power expense, $64,720.

For double the present car mileage the operating expenses would be approximately double and would be close to $120,000 annually. In case of such extension a 1,000 H. P. unit should be added to the plant and placed at tide-water. It could then be made compound condensing and made to do the greater part of the work with considerable saving of fuel. The electric system could be operated to Tillary street without any additional expense for motive power.

Estimate of substituting electric motors for the locomotive shifters on the New York and Brooklyn Bridge, on basis of present car mileage and separate power plant :

Power Plant: Real estate, $5 per H. P.; building, $10 per H. P.; boilers and furnaces, $17 per H. P.; piping, pumps, etc., $3 per H. P.; engines, condensers and foundations, $25 per H. P.; generators and switchboard, $20 per H. P. Total, $80 per H. P.

Cost of 1,000 H. P., $80,000; cost of line, $4,000; cost of motors, controllers, equipment, etc., at $10,000 per train, fifteen trains, $150,000. Total investment, $224,000.

Operating Expense-Power Plant: Fuel per year, three pounds of coal for each horse-power hour, $1,717; water, $171; oil and waste, $171.

Wages: One superintendent and electrician, $2,000; two engineers, $2,400; two assistants, $2,000; two firemen, 1,400 H. P. hours per day, $1,500. Total, $9,959.

Interest, 5 per cent. on $80,000, $4,000; maintenance, 4 per cent. on $80,000, $3,200. Total, $17,159.

Operating expenses line, $369; operating expenses motors, $19,500. Total, $19,869. Total motive power expenses of shifting with present car mileage, $37,019; per day, $191.

Investment for double the present traffic, $466,000; total motive power expense on basis of double the present car mileage, $68,150.

Cable Expenses: Coal, $16,148; water, $1,101; repairs, $4,248; wages, $21,702; supplies, $9,718. Total, $52,917.

Grand total cost of motor-power for switch engines and cables, $113,825.

The following was the cost of operating the bridge cars for twelve months ending Dec. 1, 1891:

Number of passengers carried, 39,766,043; number car miles run, 615,562 trips, at 2 miles per trip, 1,269,597. Fuel, $14.690; water, $554; repairs, $8,276; wages, $31,968; supplies, $5,420; cost of locomotives, 109,528 miles run at 55.6 cents per mile, $60,908.

Subtract from $113,825, which represented the cost of operating the bridge in 1891, the estimate of the General Electric Company, which is $64,720, the apparent annual saving in favor of the use of electricity would be $49,105.

TROLLEY CURRENTS AND RAILROAD SIGNALS.

English engineers have taken warning by experience with electrolysis on this side of the water and the Board of Trade has laid down various requirements for the control of the circuits of electric street railways. In the course of the discussion before the Board of Trade during the drawing of the regulations, the question arose whether the wandering earth current from an electric railway might not reach the track circuit of a block signal system on a steam railway line, set the signal at safety when it should be at danger, and thereby cause a serious accident. In ordinary signal. ing practice, the semaphore drops by gravity to the danger position and is raised by an electric current to safety. When it is remembered that the wandering earth current of electric railways is sufficiently powerful to work electric bells and telegraph instruments, and has even, in some cases, we believe, been made use of for incandescent lighting, the possibility that, under proper conditions, such a current might cause a semaphore to show a wrong indication would seem to be by no means remote. It is true that no instance of this sort has thus far been made public; but it is to be remembered that electric railways are still a novelty and little used outside of the United States, and that only a fair beginning has been made_in_the equipment of this country's railways with block signals. Besides this, many things occur in railway service which are long in being made public, and because no instance of the turning of a semaphore in the manner described is on record, it does not, therefore, follow that none have occurred or may not occur in future.—Engineering News.

who attends both to engines and dynamos, that when the whole plant is in operation the circuit breaker often blows out without the engineer hearing it and consequently often remains open quite a while. The superintendents of these plants generally try to cut expenses and object to installing any apparatus that is not absolutely necessary, and on these occasions for an outlay of $8 to $10 I have been able to place the following alarm on the circuit which rings a 7" gong while the circuit breaker is open and the instant it is closed immediately ceases to ring, and it does this without the use of batteries or any attention whatever. I think the diagram herewith will be almost self-explanatory:

Two circuits are required, one on each side of the circuit breaker, one to ring the bell and the other to operate the switch. The operation is as follows: The magnet M attracts a pivoted lever L, which completes a circuit through a cup of mercury 2, which cuts the bell out. When the circuit breaker opens, the magnet releases the lever L which makes contact through cup 1 and consequently rings the bell which has a 7 inch gong. A shunt of 100 ft. of No. 30 wire from the negative binding post to the vibrator post prevents sparking at the bell contacts. I think this scheme is in use in several Iowa stations, having been seen and approved of by visiting electricians.

ELECTRIC LOCOMOTIVES FOR THE BERNESE OBERLAND. It is stated that the Bernese Oberland Railway Co. is contemplating the substitution of electric traction for steam, the scheme comprising 200 h. p. locomotives with 10 trains on the line simultaneously, water power being used as the source.

ELECTRIC HEATING FROM RAILWAY POWER STATIONS.

BY A. H. PERKINS.

IN THE ELECTRICAL ENGINEER for May 30th I find another contribution to the subject of electric heating. This subject has received considerable attention of late, but I have not seen mentioned a scheme which appears to have more of the elements of success in it than most writers have found in the problem.

In small electric railway plants the variation in load is extreme, and the prime mover must be of sufficient size to furnish the maximum output; so that it often happens that the prime mover cannot be of the right size to produce even the best average result, while this best average result is one of low efficiency under such varying loads. To obtain some data on the effect of electric railway loads on engine economy, I made, recently, some computations. The subject of engine economy at different loads has been worked up very carefully by Prof. R. C. Carpenter, and very useful and interesting results are given by him in the Proceedings, Am. Inst. Elec. Engrs. of May, 1893. These results embody such a large number of tests that they should be reliable. In making the above-mentioned computations I took a power curve of 25 minutes duration, traced by an automatic recorder, and divided it into 50 convenient parts with respect to time. The average power for each part was then multiplied by the length of the time, and this product by the steam consumption at that rate of output obtained from Prof. Carpenter's diagrams. In this manner the total steam consumption for the generation of the whole power was obtained and the efficiency under the changing load reached.

I found that under the conditions treated, the steam consumption was increased by 17 per cent. above that which would have been used had the engine worked at its best load at all times. The maximums and minimums in a power curve are not of long duration on a small road. It would therefore be possible to fill up the low places in the power curve, and use the extra energy for heating by turning the extra power at low points of the power curve into heating mains. Details of an automatic device for this are simple and will suggest themselves. An extra circuit is, however, required.

Suppose now that we have a small plant with such an arrangement. Neglect the effect of any benefits to be derived from increased efficiency under the steadier loads, and suppose coal to be consumed in direct proportion to the number of H. P. hours of power used. The only items of cost increased are those for coal, oil, waste and water. Where slack costing $1.50 at furnace door is used, the consumption will be about 5 lbs. per E. H. P. hour and the cost for the items named above will be 0.5 cent per E. H. P. hour. 24 E. H. P. hours are about equivalent to 46 lbs. of coal burned with an efficiency of 10 per cent. Hence with coal at $5.50 per 5.50 X 46 2,000

ton delivered, the cost with coal is = $0.126. With the above cost per E. H. P. hour, the same test from electricity costs' with 100 per cent. efficiency 24 X 0.005 $0.120. Interest on extra circuit and apparatus may bring this up to the cost given for coal.

Attendance for the coal plant has yet to be considered. With a furnace burning 7 tons in the six cold months, attendance figures up at $0.10 for burning 46 lbs. When the work is cooking or office warming, to which such a system is best adapted, the margin of profit to be made by the sale of this energy would seem to be greater than is furnished by most lines of business; for not only is 10 per cent. a high figure for the efficiency of coal directly burned for these purposes but the factors of handiness and cleanliness are representable in cash.

MAILS BY ELECTRIC CAR IN MONTREAL.

MR. G. C. CUNNINGHAM, managing director of the Street Railway Company says that it is intended to build special mail cars, each containing a staff of clerks who would sort the mail on their way to and from the various city suburbs. He has seen the postmaster in regard to the scheme and that gentleman has approved of it. It is understood that the Government is willing to adopt the new method of carrying the mails from one part of the city to the other.

BOSTON OVERHEAD WIRES ORDERED DOWN.

THE WEST END STREET RAILWAY has been formally notified of an order passed by the Board of Aldermen on April 16, to remove all the feed and return wires of its overhead trolley system in the crowded parts of the city and place them underground. The road is given until November 15 next to complete the work. The Western Union Telegraph Company, the New England Telegraph and Telephone Company, and the Boston Electric Light Company have also been ordered to place their wires underground in certain parts of the city.