Intelligence and Miscellaneous Articles. 407 



By repeated remelting, the electromotive force of the alloy is in- 

 creased. 



Or he used a combination of Argentane (known as Alpacca, from 

 the Triestinghofer metal-manufactory) with the above negative 

 metal ; or an alloy of 



65 parts of copper, 



31 ,, zinc 

 as positive metal, and an alloy of 



12 parts of antimony, 

 5 ,, zinc 

 as negative metal. 



The bars are not soldered together, but bound by means of screws. 



The positive metal melts at about 1200° C, the negative at about 

 600° C. 



As in this element it is only the heating of the positive metal 

 which influences the development of electricity, the arrangement 

 has been made that only this is heated, while the negative metal 

 receives heat by conduction. By this arrangement it is possible to 

 apply temperatures of even 600°, and consequently to attain greater 

 differences of temperature. 



An interesting illustration of the conversion of heat into electri- 

 city is the fact, that the water which is used for cooling the second 

 point of contact of the element becomes warm very slowly as long 

 as the circuit is closed, but pretty rapidly if it is open. 



The thermo-pile in question was constructed with a view to being 

 used with a gas-flame. The individual elements consist of bars of 

 unequal dimensions; the positive electrical bar is 7" long, 7'" broad, 

 and I'" thick ; the negative electrical bar is 6" long, 7'" broad, and 

 6'" thick. Thirty-two such elements were screwed together, so that 

 all positive bars were upon one, and all negative on the other side, 

 and thus had the form of a grating. The battery consists of two 

 such gratings, which are screwed together in a roof shape, and are 

 strengthened by an iron bar. As an insulator between the iron bar 

 and the elements, mica was used. Besides this, the elements, where 

 they came into contact with the cooling water, were coated with so- 

 luble glass. An earthen vessel filled with water was used for cooling 

 the lower contact sides of the elements. The entire battery has a 

 length of 2 feet, a breadth of 6 inches, and a height of 6 inches. 



M. Marcus communicated further, that he had constructed a 

 furnace which was intended for 768 elements. They represent a Bun- 

 sen's zinc-carbon battery of thirty elements, and consume per diem 

 240 pounds of coal. — Sitzungsbericht der Akademie in Wien, No. 8, 

 1865. 



ON PRODUCTION OF MAGNETISM BY TURNING. BY C. B. GREISS. 



On a visit to the central workshop of the Nassau Railway, I was 

 struck by the perfect winding of the shavings of cast steel, which 

 were just like a thin rope ; and on investigating a specimen I found 

 that it had two well-pronounced magnetic poles. Subsequently I 

 obtained from the same place a number of shavings of different ma- 

 terials — cast steel, puddle steel, and soft iron. By means of a not 

 at all delicate magnetic needle I found that they all possessed po- 



