124 KANSAS CITY REVIEW OF SCIENCE. 



The steam rollers employed weigh about thirty tons each. The rolling is 

 generally completed in a single night. — Van Nostrand' s Magazine. 



BERLIN'S ELECTRIC RAILWAY. 



Our Berlin correspondent, describing the new electric railway there, already 

 referred to in a telegram, says that the system, which has been in use in Berlin 

 for more than a year, has not proved a financial success. It has also been found 

 that there is some inconvenience attending the transmission of the electric current 

 through rails. A horse, while crossing this line, striking it with his shoe, re- 

 ceived a severe shock. It is impossible, moreover, to repair or remove the rails 

 without the suspension of traffic over the entire route, since such removal inter- 

 rupts the current. Herr Siemens, to meet these and other objections, devised 

 his new system, which is far more practicable than the first. Over the entire 

 line two cables are suspended parallel to and about twelve inches from each oth- 

 er, on poles approximately sixteen feet above the ground. Along these cables a 

 system of wheels passes, connecting with the tram car by another cable, which 

 can be detached from the car at pleasure. The cables are charged with electric- 

 ity, which is generated at a station about the middle of the route, and which is 

 taken up by the apparatus as it runs over them. It then passes through the con- 

 necting cable, down beneath the tram car over a system of drums which unites 

 with the running gear. The apparatus passing along the suspended cables either 

 precedes or follows the car. The speed of the vehicle is regulated by a crank, 

 and a complete stop can be made as readily as if it be drawn by horses. On 

 Saturday, during the trial, two cars were run, first separately and aiterward to- 

 gether. In the first case two distinct connecting cables are necessary, while in 

 the second one answers the same purpose, the electricity passing through the 

 car couplings, the only difference being a diminution of velocity owing to the ad- 

 ditional weight. The length of the route run over on the trial trip is about three 

 miles, a portion of the distance being up hill, an inclination of i° to 28°. A car 

 can be run up the grade at the rate of from fifteen to twenty miles an hour, while 

 on a leoel it will make thirty miles to the hour. After having thoroughly tested 

 the working of the railway, visitors were driven to the country to witness the 

 operation of a car which Herr Siemens has invented. It also is propelled by 

 electricity on the same principles as those described for the tram cars. It runs a& 

 smoothly as a common carriage, and is perfectly manageable. It is directed by 

 the driver, who sits in front, by turning a wheel very similar to those used in 

 steering ships, and is started or stopped by a simple pressure made upon a lever. 

 This car is intended to run between towns whose populations are too small to make 

 a railway profitable pecuniarily. " It appears to me," adds our correspondent, 

 "calculated to meet this end when once the question of its economy over the 

 running of stage coaches has been demonstrated." — London Daily News. 



