OF ARTS AND SCIENCES. 19 



III. 



WHAT ELECTRICITY IS: ILLUSTRATED BY SOME 

 NEW EXPERIMENTS. 



By W. W. Jacques. 



Presented January 13, 1892. 



Electricity is, to all of us, more or less surrounded with an 

 atmosphere of mystery. 



When we speak of Light, or Sound, or Heat, we feel that we are 

 dealing with familiar things, — things so familiar to our every-day 

 life that it seems useless to try to define or describe them. Every- 

 day the sunlight fills all space; it dazzles our eyes; it falls upon 

 the objects around us, and makes them visible ; and though 

 through the evening, when the sun is gone, we substitute for a 

 while a gas flame, or a candle, or an electric light, we have then 

 through the day had so much of it that at night we are glad to be 

 rid of it, and have darkness for our hours of repose. 



So, too, from babyhood to old age, all day long and every day, 

 we are listening to one or another sound, whether the voices of 

 friends, or the busy hum of city life, or the delights of music, or 

 the ticking of the clock at night. Indeed, so constantly are our 

 ears filled with sounds, that, when we go alone on to a high moun- 

 tain, or a desert plain, where there are no trees to rustle with the 

 wind, the silence is painful and oppressive and awful. 



Heat, too, is equally familiar, perhaps even more so : for what 

 is more familiar than the warmth of sunshine? And is not the 

 fireside the very centre, as well as emblem, of our home? 



When, however, we speak of that other great force of nature, 

 Electricity, we feel that we are departing from familiar ground. It 

 is shrouded in mystery; it is something we cannot see, or hear, or 

 feel, — something we cannot easily describe or define. We speak 

 of it in the same breath with spirits and with ghosts. The rea- 

 son, I take it, is because the human body has no organ especially 

 adapted to recognize electrical phenomena. While the eye re- 

 ceives the ray of light, the ear the ray of sound, and any part of 



