AMERICAN INSTITUTE. 389 



Jacket of air, as it is called, the temperature is maintained twenty-four 

 hours longer than in single walls. 



Mr. Veeder again spoke of combustion, of the eifect of blowers on fur- 

 naces, causing the hydrogen at the tops of flues to burn blue. 



Mr. Seeley. — Currents of air in rooms are well shown by smoke — but 

 no room can be without currents of air — but they must not be strong. 



Mr. Brown summed up arguments and showed plainly that the several 

 .methods were adapted each to a different class of buildings. He explained 

 the ready freezing of steam pipes, and the great care and engineer skill 

 demanded in the management of the apparatus, puts it above private 

 Ijuildings. He reviewed all the processes of heating and ventilation, and 

 said that it was essential that he who found any want of either must then 

 seek the remedy for his own special circumstances, or in plain terms, each 

 must have suitable appliances in his own case, no other case being pre- 

 <;isely the same. That enough was known to some men to suit every case ; 

 but it was like the doctor among patients of very diverse habits and con- 

 stitutions ! Mr. Brown had repeated his own remarks, but the community 

 would require repetition on repetition in order to fractice the most estab- 

 lished laws of temperature and ventilation. 



The Club proposed, for nest meeting, the subjects of *' Boilers and 

 Combustion," and " Canal Steam Navigation." 



The Club adjourned, 



H, MEIGS, Secretary. 



December, 22, 1858. 

 Present — Messrs. Butler, Johnson, Brown, Seeley, Bruce, Cohen, and 

 others — 16 members. 



Mr. Butler in the chair. Henry Meigs, Secretary. "^Jj 



The Secretary i*ead the following papers, viz : 



[Society Oif Arts. London, 1858.] 



ELECTRO-MAGNETISM AS A MOTIVE POWER. 



Would it not be reasonable to compare it with the steam engine when 

 Watt took it in hand, and before he had found a Bolton to assist him with 

 capital ? Had Watt not found a capitalist, he might have died and 

 made no sign, and the gigantic improvements resulting from his genius 

 would have remained undeveloped. The question is confessedly a very 

 great one, and admits of a division of labor ; and if chemists would turn 

 their attention to the discovery of a cheaper substance than zinc in the 

 battery, a material point would be gained. I think the three following 

 improvements may be justly claimed by Mr. Thomas Allen : 



1st. The application of the magnetic force direct, and not tangentially, 



2d. The use only of the most powerful portion of the geometric curve, 

 formed by the rapidly decreasing magnetic power in proportion to distaucei. 



3d. The continuations of motion or stroke, in the same direction, ove» 

 any required space bj means of successive groups of magnets. 



