5 76 POPULAR SCIEXCE MONTHLY. 



electro-motive force to produce death, but the shock is nevertheless 

 very severe. Horses and cattle would be killed outright, as these 

 animals are not able to withstand as strong a shock as human beings. 

 To render the third-rail system safer, and also to improve the insu- 

 hition of the conducting rail, the construction illustrated in Fig. 31 

 has been devised. The only dilference between it and Fig. 29 

 is that the rail h, instead of resting upon the ties between the tracks, 

 is carried upon a side support c c and is housed in with boards a a. 

 To take the current from it a wheel is mounted upon a shaft pro- 

 jecting from the side of the car truck. 



From the foregoing brief descrij^tion of the essential features 

 of the several systems devised for conveying current to the moving 

 car by means of conductors placed underground or upon the sur- 

 face, it can be seen tliat while the result can be accomplished in 

 many ways, and is actually accomplished in a number of instances, 

 nothing has been brought forward so far that is as free from objec- 

 tion as the simple trolley, if we disregard the unsightliness of the 

 latter. It is this unsightliness that has created a demand for some- 

 thing else, but the substitutes, while capable of doing the work, are 

 far more costly and can not be said to be as reliable under all con- 

 ditions of weather. 



The sphere of action of the electric-railway motor is not con- 

 fined to street railways or suburban transit, but extends to the 

 legitimate domain of the steam locomotive. In many places elec- 

 tric locomotives are used to move freight trains made up of cars 

 of the largest capacity, this same work having been done formerly 

 by steam locomotives. In the city of Baltimore, the Baltimore 

 and Ohio Kailroad uses electric locomotives, of greater capacity 

 than any steam locomotives so far made, to draw trains through the 

 tunnel that passes under the city. The general appearance of an 

 electric locomotive can be judged from Fig. 32, which shows an 

 engine of average size at the head of a long freight train. 



MM. Bertaux and G. Yver are quoted, in La Nature, as relating in 

 their travels in Italy that between Benevento and Foggia, where the 

 railway passes through a tract of wheat fields, a falcon was observed closely 

 accompanying the train. He would graze the windows, fly over the roofs 

 of the cars and turn, and keep constantly dashing down to the ground 

 by the side of the track. A habitual traveler on the road remarked that 

 he had obsei-ved this habit of the bird several times a week. The crafty 

 hawk had observed that the eddy made by the train as it rushed through 

 the air overcame the small birds and made them an easy prey, and it had 

 learned to take advantage of the fact. It was also remarked that this 

 particular train, wliich was the "fast train," was the only one the bird 

 thus pursued. 



