338 J. Nicklés on Different Applications of Magnetic Attraction. 
this supplement of adhesion, and in fact, on closing the circuit, 
ar passed over the rails without difficulty ; ; on breaking the 
ormnciliel again, it stopped and fell back on the track. ‘The 
weight A used in the experiment was two kilogrammes, and the 
motor weight B about six. The figure is reduced to one-fifth the 
lineal dimensions. 
In this experiment, the adhesion derived from the weight of 
the engine was obviously replaced by another force differing in 
being independent of the grade of the track, since the magnetic 
attraction anes acts perpendicularly to the plane of the arma- 
ture whatever may be the position or inclination, while gravity 
acts at right nia toa true horizontal plane. The constancy 0 
the magnetic —— is —* by means of a piece of apparatus 
which is described bel 
Although this sicetirenit was so simple and unpretending, it 
afforded an encouraging demonstration of the problem in view, 
and it has interested the different — of physics of Paris, 
MM. Despretz, Becquerel, Silbermann, ete., who have exhibited it 
in their courses, as well as the sake experiments below detailed. 
The process just explained would certainly have been very sim- 
ple, if the successful application on a large scale had required ouly 
that an electro-magnet should be placed on each side of the driving 
wheels. But this method would not stand the most elementary con- 
siderations. ‘The 
ble method seem- 
ed then to consist 
igs. 2 and 3 rep- 
