AMERICAN INSTITUTE. 619 



GALVANISM AS AN INDUSTRIAL AGENT. 

 France decreed a prize of 50,000 francs, in 1852, for the dis- 

 covery of means of rendering the galvanic battery commercially 

 available in the industrial arts, light, heat, as a chemical or medi- 

 cal agent, as a mechanical power. A committee is now formed 

 for the purpose of examining and reporting upon the offers iu 

 competition. 



Dumas, president of the committee; Messrs. Chevreul, Pelouze, 

 Eegnault, Despretz, Rayer, Serres, Charles Dupin, Sequier, Pon- 

 celet, Morin, of the Academy, and Reynaud, director of Light- 

 house, and Henry St. Clair Deville, of the Normal Scliool. 



The Emperor of France has ordered a committee to examine 

 and report upon a new electro-magnetic engine recently invented 

 by Thomas Allen, of England. His engines are now at work in 

 Paris, and it is said, will be applied to locomotion. 



PAVING AND PAVEMENTS. 



Mr. Hildreth — The specimen of rock on the table is a conglom- 

 erate of quartz pebbles, which appears to be too friable to become 

 of economical value as a pavement. This rock, however, is very 

 justly esteemed of value and importance in the construction of 

 furnaces for the smelting of iron and other metals, as it has quali- 

 ties of a refractory character, in which respect it resembles the 

 fire brick, which is composed of quartz pebbles mixed with the 

 clay of the coal measures, which is shaped in blocks about double 

 the size of the ordinary brick, and then subjected to a constant 

 high heat in kilns peculiarly adapted for the purpose, and then 

 becomes like this rock, a refractory or fire brick. 



The city of New- York has tried many experiments in paving, 

 which have demonstrated many important facts. These experi- 

 ments have shown the incomparable advantage of a very "tough" 

 rock, obtained directly opposite the city, on the New Jersey shore 

 of the Hudson river, which is known to geologists as Blue Trap 

 rock. This is the rock which, upon Broadway, has been laid 

 down in blocks from twelve to fourteen inches square on the sur- 

 face, and is known as the Russ pavement, and subsequently the 



