Of the various branches of electrical investigation, perhaps the most interesting and immediately the most promising is that dealing with alternating currents.

As in nature, all is ebb and tide, all is wave motion, so it seems that in all branches of industry, alternating currents - electric wave motion - will have the sway.

Electrical science has revealed to us the true nature of light, has provided us with innumerable appliances and instruments of precision, and has thereby vastly added to the exactness of our knowledge.

When a coil is operated with currents of very high frequency, beautiful brush effects may be produced, even if the coil be of comparatively small dimensions. The experimenter may vary them in many ways, and, if it were nothing else, they afford a pleasing sight.

Electrical science has disclosed to us the more intimate relation existing between widely different forces and phenomena and has thus led us to a more complete comprehension of Nature and its many manifestations to our senses.

The harness of waterfalls is the most economical method known for drawing energy from the sun.