PROCEEDINGS OF THE POLYTECHNIC ASSOCIATION. 973 



between their most powerful acting parts, the extremities, or so- 

 called poles. 



In order now to mnke the diaraagnetic theory applicable t-o 

 Porter's arrangement, or so called steam l)attery, the idea of Perry, 

 of suspending magnets in the boiler, has been combined Avith it, 

 and the little pohits Porter speaks of (but which he had no idea 

 of magnetizing), have been magnetized — a perfect useless and 

 absurd operation, solely introduced to cause the apparatus ap- 

 parently to agree with the preconceived diamagnetic theor3^ 



I call the magnetizing of these small points absurd, for the 

 following reason: When points are only two or three inches long, 

 and of the thickness of a lead pencil, their power is so weak that 

 they can scarcely support a common nail, and it cannot be made 

 more; on the contrary, it is always greatlj^ diminished, and always 

 ultimately destroyed by the high temperature to which they are 

 submitted in the steam room of a boiler. 



How any one, who pretends to a scientific knowledge, combined 

 with common sense, can possibly seriously assert that these small 

 magnetic points, when suspended in one corner of the steam room 

 of a large boiler of several tons weight, will "put the whole entire 

 surface of this boiler in a condition of magnetic polarity," so that 

 it will "forcibly keep av/ay from the iron surface " all diamagnetic 

 bodies, and even loose the scale already formed, " so that the 

 pure water will penetrate between the mutually repellent surfaces 

 of scale and iron when the latter becomes magnetic," all this is 

 moi'o than I can understand. 



It appears that in some localities, for instance, at the iron works 

 along the Lehigh river, the incrustation in the boiler is formed so 

 rapidly that the insufficiency of the apparatus is proved every 

 three months; but then the magnetic points are o-ood for such a 

 contingency, they are blamed as being the cause, by having lost 

 their magnetic power; they are removed, and of course found very 

 weak, like they necessarily become in all boilers. New, fresh 

 ones are inserted; but nothing is easier than at the same time to 

 introduce some soda, sal ammonia, gum catechu, etc., which in a 

 few weeks will loose the old scale, and during a few months pre- 

 vent the formation of hew scale; and Ihen all the credit may be 

 given to the freshly magnetized points of the anti-American 

 incrustator. 



I v/ill now notice two other patents of a similar nature, one 

 granted anterior to all the above, the other recently issued. 



