214 nature's 



two conductors running to the furnace have a 

 cross-section of eight square inches, and this 

 enormous current, representing over 1000 

 horse-power, is passed through the core of the 

 furnace, and is kept running through it con- 

 stantly for a period of twenty-four to thirty- 

 six hours. 



Let us consider for a moment what 1000 

 horse-power means; as this will give us some 

 conception of the enormous energy expended 

 in producing carborundum. A horse-power is 

 supposed to be the force that one horse can 

 exert in pulling a load, and this is the unit of 

 power. However, a horse-power as arbitrarily 

 fixed is about one-quarter greater than the 

 average real horse-power. If 1000 horses \\cn; 

 hitched up in series, one in front of the other, 

 and each horse should occupy the space of 

 twelve feet, say, it would make a line of horses 

 12,000 feet long, which would be something 

 over two miles. Imagine the load that a string 

 of horses two miles long could draw, if all were 

 pulling together, and you will get something 

 of an'idea of the energy expended during the 

 burning of one of these carborundum furnaces. 



Within a half hour after the current is 

 turned on a gas begins to be emitted from the 

 sides and top of the furnace, and when a match 

 is applied to it, it lights and burns with a 

 bluish flame during the whole process. It is 

 estimated that over five and one-half tons of 



