Boiling Water Without Fire.

Pukekohe & Waiuku Times, Volume 4, Issue 22, 19 March 1915, Page 3 (Supplement)

Boiling Water Without Fire.

It is possible to make a pail of water boil without putting it on the fire and without applying external heat to it in any way. In fact, you can make a pail of'water boil bv simply stirring it with a. wooden paddle. The feat was performed in the physical laboratory oi Johns Hopkins University in Baltimore, Md.. and anyone may do it with a little trouble and perseverance. All you have to do is to place the water in a pail—it mav be in water if necesary—and stir it "with a wooden paddle It you keep at it long enough it will certainly boil. Five hours of constant and rapid stirring are sufficient to perforin the feat successfully. The water will, after a time, grow warm, and then it will prow hot—so hot, in fact, that you cannot hold vour hand in it, and finely it will boil. Professor Ames, <t Johns Hopkins, annually illustrates some of the phenomena of heat by hnv-in-r one of his students perform the trick in front of his class. Tt is a tiresome job, but it is perfectly feasible. The point which Professor Ames wishes to illustrate is what is known as the mechanical equivalent of heat. It requires just so many foot-pounds of work to "develop a given quantity of heat. Bv turning the paddle in the water at' a regular speed it is possible to find out just how much work is required to raise the temperature of water one degree. The best measurement so far made, and, ill fact, the one which is accepted as the standard of the world, is that which was measured in Johns Hopkins College. Heat is developed in almost any substance which is subjected to continuous or very violent action. It is an old trick for a blacksmith to force without fin'. Long-continued and violent hammering on two pieces of wire will heat them to such an extent that they can be welded together.