CHAP, i.] OSCILLATIONS OF THE PENDULUM. 



27 



2. At the equator, on the other hand, the rotation of the globe 

 would not have any influence on the apparent direction of the plane 

 of the oscillations, which would appear to be, and indeed would be 

 always the same relatively to the horizon. 



3. Lastly, theory establishes that in all other latitudes the ap- 



Fu;. 8. Foucault's pendulum experiment. 



parent deviation of the plane of the oscillation of the pendulum would 

 be made in the direction of the nearest pole, the deviation being- 

 slower according as the place where the experiment is made is nearer 

 the equator. Calculation shows that at Paris (latitude 48 50') the 

 pendulum would take about thirty-two hours to accomplish the 

 entire round of the horizon, friction at the point of suspension and 

 that due to the resistance of the air not beiii taken into account. 



