MECHANICS AND USEFUL ARTS. 93 



powers and ingenuity ought to have awarded him, while other men 

 have realized fortunes, and continue to do so, from the information 

 imparted by the knowledge of Dr. Feuehtwanger. In 1837 the Doc- 

 tor petitioned Congress to grant him permission to issue $30,000 

 worth of pennies made of his composition, as an experiment to sub- 

 stitute the German silver for the copper currency, and John Quincy 

 Adams and Mr. Benton spoke in the highest terms of this proposition, 

 and it met the approbation of the President and the members of both 

 Houses. He failed, nevertheless, on account of the unfavorable re- 

 port of the Directors of the Mint, who stated that the right of coin- 

 age belongs to the Government, and that it required some skill to 

 analyze the German silver. Hunfs Merchants' Magazine. 



FRAUD IN THE MANUFACTURE OF GOLD PENS. 



A RECENT examination of some gold pens in the laboratory of the 

 Lawrence Scientific School, Cambridge, showed that they were com- 

 posed of galvanized iron, coated with an extremely thin plating of 

 gold. The pen was apparently at first stamped from thin sheet-iron, 

 then coated with zinc, and lastly with gold, the last being put on by 

 galvanic electricity. The combination of zinc and iron to form the 

 body of the pen was most ingenious, and adapted to prevent corrosion, 

 as the pen resisted the action of the strongest a'cids for some time. 

 The pens were stamped as the " Cobden Pen," and not with the 

 name of any manufacturer. Editors. 



SALT IN NEW YORK. 



FROM a letter from Mr. Gere, the superintendent of the Syracuse 

 Salt Springs, we learn that the quantity of salt manufactured during 

 the season amounts to about 5,066,000 bushels, being an increase of 

 330,000 over any previous year. Salt has declined in price the whole 

 season, finally coming as low as 65 cents per barrel, including the 

 duty. The only new shaft sunk is one at Salina, to a depth of 220 

 feet, being 40 feet more than any other at that place. With the 

 proper deductions, the price received for the salt is but 38 cents for a 

 barrel of live bushels. 



BLAKE'S PATENT FIRE-PROOF PAINT. 



THIS new fire-proof paint is formed from a peculiar mineral sub- 

 stance found in large quantities in a stratum of rock in Sharron, Ohio. 

 It is composed of "silica, alumina, protoxide of iron, and magnesia, 

 with a small admixture of lime and carbon. It has the appearance of 

 the finest indigo ; but a few days' exposure turns it to a hard stone. 

 The examining committee of the fair of the American Institute, of 

 1848, reported that it was an article superior to every thing that had 

 previously been presented, as a fire and weather proof covering, and 

 awarded "to Mr. Blake a medal. The fair of the State of New York, 

 held in Buffalo, also awarded a medal. The agents of all the fire-in- 



