324 



SCIENCE. 



[Vol. XII. No. 308 



and digging new canals for deviating rivers, etc., but these works 

 are far more formidable in Panama than on the Isthmus of 

 Nicaragua. The control of the Chagres River has been one of 

 the most serious obstacles to successfully carrying on the work 

 at Panama. On the route selected for the Nicaragua Canal by 

 the surveying party of 18S5, obstacles of a similar kind would 

 have been encountered in the basin of the Rio Grande between 

 Lake Nicaragua and Brito ; but in the new plan of l888 this diffi- 

 culty has been overcome by damming up the river, and transform- 

 ing its valley into an artificial lake, the Tola basin. 



On the profile of the Panama Canal may be seen both the vol- 

 umes to be excavated for the purpose of establishing a lock- canal 

 and a sea-level canal. The number of locks necessary for the former 

 is ten, while the plan of the Nicaragua Canal contemplates only six 

 locks. A single glance shows that by far the greater amount of 

 work necessary to complete a sea-level canal remains to be done, 

 and that comparatively little has been accomplished in the most 

 difficult sections of the canal. While it seems impossible to com- 

 plete the deep Culebra cut on account of the movements of the soil, 

 no such difficulties are anticipated in the short deep cut of the 

 Nicaragua Canal crossing the eastern divide. Careful borings have 

 shown the soundness of the rock. 



If we consider that the Nicaragua Canal Company is just start- 

 ing its work, while the Panama Canal Company is burdened with 

 an enormous debt ; that the amount of work left to be done is 

 smaller in Nicaragua than in Panama, — we must regard the pros- 

 pects of the former as very encouraging. 



The profile of the Panama Canal shows, on the other hand, the 

 amount of work done as compared to that left unfinished. Much 

 money has been expended; and the interests at stake are so powerful, 

 that we do not believe the work will be dropped, but will be pursued 

 in some way or other. A decrease of the working force seems to 

 be, however, at present unavoidable, and this will relieve the Nica- 

 ragua Canal Company of another difficulty, the scarcity of work- 

 ingmen in these tropical regions. If the work on the latter is 

 undertaken without unnecessary delay, and if it is continued as 

 carefully as the preliminary surveys warrant it will be, we expect 

 to see it completed at an early day. The Panama Canal, even if 

 opened at a later day, will have to contend against an established 

 route, run at smaller expense than its own, as the capital invested 

 and the number of locks, which cause increased expense, will be 

 smaller. , 



THE SPRAGUE ELECTRIC ROAD AT BOSTON. 



We take pleasure in presenting our readers in this issue of our 

 paper with a general view of the new electric street-railway between 

 Boston and Brookline, installed by the Sprague Electric Railway 

 and Motor Company of New York. There have been several trial 

 trips made over this railway already, to test the apparatus, which 

 has been found to be perfect, and the road will be put into com- 

 mercial operation in a few days. 



The West End Street Railway of Boston, of which this road is a 

 part, is the largest street-railway in the world. It extends over 212 

 miles of track, using 1,700 cars and more than 9,000 horses. The 

 president of the West End Street Railway Company, Mr. Henry M. 

 Whitney of Boston, is universally recognized as being one of the 

 most enterprising and successful street-railway men in the country, 

 and, aided by an efficient corps of assistants, has succeeded in giv- 

 ing Boston since his administration the most efficient street-railway 

 service which ever existed in that city. 



Before deciding upon any electric system to be adopted upon the 

 West End Road, President Whitney, accompanied by members of 

 the board of directors and managers, visited all the principal elec- 

 tric railways in the country operated upon the various systems, in- 

 cluding visits upon three different occasions to Richmond, Va., to 

 inspect the famous electric road in operation there upon the Sprague 

 system. After a most careful examination of all these different 

 roads, the contract for equipping the West End Road was awarded 

 by the board of directors to the Sprague Electric Railway and Mo- 

 tor Company of New York. 



This system of electric railway called for in this contract is wide 

 and comprehensive. The main line from Boston westward, begin- 

 ning at Park Square, will run down Boylston Street bridge, and 



then down Chester Park to Beacon Street. It will then proceed 

 over the Beacon Street extension to the Chestnut Hill Reservoir, 

 and to Allston, and Oak Square, Brighton. From the East Park 

 gate, over the new boulevard to the Chestnut Hill Reservoir and 

 Brighton, the Sprague overhead system will be adopted ; in the 

 more crowded streets of the city the Bentley-Knight conduit will be 

 used ; and the Sprague cars will run over the whole system. 



The power-station from which the electric current is distributed 

 to the line is situated on Braintree Street, Allston, near the Boston 

 and Albany Railroad, and also at the edge of the water, thus giving 

 both water and rail facilities for fuel. This building, which is the 

 most perfect electric plant of its kind in the country, is situated 

 very nearly equidistant from the extremities, and is therefore liter- 

 ally a central station. The station, with the adjoining car-house, 

 is of brick, and completely fire-proof. 



In its construction it was the aim of the West End Company to 

 get the best in every detail. The chimney-stack is 100 feet high. 

 The boiler-house, which is both convenient and commodious, is at 

 present equipped with three horizontal tubular boilers, furnished by 

 the Jarvis Engineering Company. The engine-room contains two 

 high-speed automatic cut-off engines of the Armington & Sims 

 pattern, of 200 horse-power each. Each drives two powerful dyna- 

 mos of 80,000 watts each, and wound for a maximum pressure of 

 500 volts. These dynamos are of the highest efficiency and sim- 

 plest construction, and, if need be, can be placed under the charge 

 of the steam-engineer. The dynamos feed into copper bus wires, 

 supported on the walls by porcelain insulators. 



Each machine has its independent ampere meter, and in addition 

 there is a general ampere meter at the end of the positive bus bar. 

 From this bar the current passes to special snap-switches, each 

 switch being connected through a three-plug safetj'-switch back to 

 one of the feeders supplying current to the main line-wire. These 

 feeder-wires tap into the line-wire at different points on the line of 

 road, thus maintaining the pressure approximately equal all along 

 the line. At the ends of the feeders in the central station, pressure- 

 indicators are attached, which indicate the voltage at the junctions 

 of the feeders with the main current-wire. 



The engine-room is brilliantly lighted by handsome hanging elec- 

 troliers, each of which has five incandescent lamps. A switch- 

 board at one end of the room furnishes an independent control for 

 each group of lamps. All the surroundings of the machines are 

 kept in the neatest condition. 



Adjoining the power-house, but separated by thick brick walls, 

 is a commodious house for accommodation of cars, 107 feet long by 

 80 feet deep, designed to hold 24 cars. 



The overhead system, which is built under the Sprague patents, 

 is of the finest description, and includes iron poles set in concrete 

 throughout the entire length of the road. These poles are of a 

 very neat and tasteful pattern, and support the span-wires which 

 carry the trolley-wire at a height of 18 feet over the centre of the 

 track. This overhead wire, which is used for a working conductor, 

 is made of silicon bronze, of the small Sprague type, only three-six- 

 teenths of an inch in diameter. This is the only wire suspended 

 over the middle of the track, and its lightness and high tensile 

 strength allow the overhead supporting structure to be of the light- 

 est description possible. The poles are 125 feet apart. 



The return circuit is through the rail, and thence by both metal- 

 lic and ground circuits to the station. Each section of rail is joined 

 to copper ground wires throughout the length of the road under- 

 neath the string-pieces. At intervals of 500 feet this ground wire 

 is connected to an earth plate, and at seven points widely distrib- 

 uted. The ground wire is connected to the station, and there is 

 also a main ground connection made there through a large sink- 

 plate. 



In the overhead system a new method of switching has been 

 adopted, which is at once ingenious and simple. Five or six feet 

 inside the turnouts a small switch with flaring rider is interpolated 

 into the main and branch wires, and a spring tongue upon this 

 directs the path of the trolley with absolute certainty and ease. By 

 this means, switching is made very easy, and all danger of the trol- 

 ley leaving the wire is obviated. 



The cars can be run at widely different speeds, varying from the 

 slowest crawl to twelve or more miles per hour. They can be 



