PROCEEDINGS OF THE POLYTECHNIC ASSOCIATION. 971 



To Prevent Ircrustation in Boilers. 

 Dr. Vauderweyde exhibited a model of his contrivance for pre- 

 venting incrustation. It consisted of a representation of the com- 

 mon horizontal boiler, to which is attached on the inside or upper 

 part of the steam room, a series of metallic rods, resembling light- 

 ning rods, pointing downwards, which were intended to carry the 

 positive electricity of the steam to the bottom of the boiler, where 

 it, discharging in the water, repels the electro-positive deposits. 

 He also presented the following paper : 



Uses of Electricity in Preventing Scale in Steam Boilers. 



Observing the mysterious and powerful eftects produced by 

 electricity, it is not surprising to find persons who ascribe almost 

 everything they cannot explain, to this agent. Thus, ur.account- 

 able steam boiler explosions were explained by " electricity," and 

 attempts were made to discharge this supposed " exploding 

 electricity " from the boiler. Others supposed that electric cur- 

 rents would prevent explosions, and confounding electricity with 

 magnetism, made all kinds of al)surd experiments, as, for instance : 

 Perry, of Philadelphia, of whom an application for patent made 

 May 2, 1864, was rejected, for reason of its absurdity. He 

 obtained, however, a patent October 31, 1865, (No. 50,773,) in 

 which he claims: First, "suspending within a steam boiler one or 

 more permanent magnets for inducing an electric current." Mag- 

 netism and electricity are not identical, they are only related 

 together, but in a much lesser and different degree than light and 

 heat,^a!id this claim of Perry is as absurd as it would be to sus- 

 pend a kettle of hot water in a room in order to illuminate it. A 

 second claim added to this patent describes a holloAv l)0x, wnth 

 isolated lining, through which a conducting rod projects — evi- 

 dently destined to give escape to the explosive electricity! 



Others, observing how electricity can shock a man, and how a 

 small battery can put his muscles in continual vibration, conceived 

 the idea of connecting the steam l)oilcr with a powci-ful galvanic 

 battery, ifi order to put it "in vibration, and shake scales or in- 

 crustation loose from it," as if a steam boiler had muscles or nerves, 

 and could possibly be shocked by electric currents. All those 

 familiar with the subject know that such a large mass of metal as 

 a steam boiler consists of, W'ill conduct the strongest electric cur- 

 rents we possil)ly can produce, silently and imperceptibly. How- 

 ever, an application for patenting this principle is at the present 



