PROCEEDINGS OF THE POLYTECHNIC ASSOCIATION. 571 



80 broken up by tlie process that it is far more effective tlian wool in its 

 natural state, which is acted on with diiFiculty by air and moisture — re- 

 quiring' about two years to render it effective as* a manure. It is found 

 that from 1,000 lbs. of the mixed fabric there may bo obtained 300 lbs. of 

 coiton, 75 lbs. of prussiate of potash, and 50 lbs. of ammonia, and, in addi- 

 tion to these, sufficient gas to light the factory and partly heat the retorts 

 tised ill the process. 



New Asteroid. 



* 



M. Tempel, of Marseilles, has just discovered a new planet, which makes 

 the eigh!;y-first of the group existing between Mars and Jupiter. Its bril- 

 liancy is tliat of a star of the 1 1th and 12th magnitude. The discovery has 

 been confirmed by the observations of M. Luther, at Bilk. 



Preservation of Wood. 



The following method is used in Germany for the preservation of wood: 

 Mix 40 parts of chalk, 50 of rosin, 4 of linseed oil, melting them together 

 in an iron pot; then add 1 part of native oxyd of copper, and afterwai'ds, 

 with care, 1 part of sulphuric acid. The mixture is applied while hot to 

 the wood, by means of a brush. When dry it forms a varnish as bard as 

 stone. 



Honor to Prof. Bond. 



The royal astronomical society at London has this year awarded, for the 

 first time to an American, its highest honor, the gold medal of the society, 

 to Professor George P. Bond, lately director of the observatory of Harvard 

 University at Cambridge, for his eminent services in the advancement of 

 astronomy, and especially for his volume on the comet of 1858. 



Stability of Gun-Cotton. 



M. Morel, who claims to be the inventor of gun-cotton in France, affirms, 

 in contradiction to the assertions of M, de Luca, that he has specimens of 

 that substance which he has kept for eighteen years without undergoing 

 the least alteration, and that, when properly made, gun-cotton will preserve 

 its properties for an indefinite period. 



Gauge of American Railways. 



As to gauge, there are three classes of railroads in the United States. 

 The New England and New York roads are four feet eight and a half inches. 

 In Ohio and south of Philadelphia they vary from this width to four feet 

 ten inches. The Canada gauge is four feet six inches, of which gauge also 

 are some of the roads of Maine. The broad gauge is six feet, of which the 

 Erie, the Atlantic and Great Western, and the Ohio and Mississippi are 

 examples. 



Turpentine at the North. 



There is a company at Freedom, N. IL, engaged in manufacturing tar 

 from pine stumps. They produce forty barrels of tar and seven or eight of 

 spirits of turpentine evei-y week. The stumps are drawn and cut up a8 



