proceedings of the polytechnic association. 881 



New Steam Plough or Spader. 



Mr. Willard exhibited a model of his patented steam plough, 

 and operated it on table covered with earth. Its novelty consists 

 in placing, side by side and lengthwise of the machine, a series of 

 bars, which are connected at each end with a crank. Underneath 

 each bar, and firmly attached to it, are several projections, like 

 spades or cultivator teeth, which, as the bar is lowered by its 

 cranks, penetrate the soil and move it in the act of leaving it. 

 This machine has not yet been tried on a large scale. The princi- 

 pal advantage in this implement seems to be that the action of the 

 teeth or spades tends to propel the machine. About eight-tenths 

 of the power of other locomotive ploughs are expended in moving 

 the machine. In this there seemed to be some saving of power 

 required for propulsion. 



Mr. Elliot suggested that there was danger of packing the earth 

 too mucli by the w^eight of the machine, although the spades suc- 

 ceed the wheels in the model shown. The general opinion ex- 

 pressed was that the plan was w^orthy of a trial on a large scale. 



Chimney Ventilator. 

 Mr. Horton exhibited an improved chimney ventilator, which 

 seemed to be similar in construction to some now in use ; but the 

 inventor claims that his ventilator w^orks equally well in every 

 direction of the wind, and is more simple in construction, and 

 therefore cheaper than ordinary ventilators. 



Gold. 



Professer R. P. Stevens spoke on the subject of gold, and sought 

 to account for the small quantity in circulation in this country. 

 Of all the gold produced in the United States, 15 per cent, is 

 employed in manufsictures ; 35 per cent, goes to Europe ; 25 per 

 cent, to Cuba and Brazil, and five per cent, to China. A large 

 proportion of that sent out of this country finds its way to the 

 east, where it is lost to commerce. A large quantity is there 

 melted down and used to form ornaments, and not less than thirty 

 per cent, is hidden or buried. The reason why bullion does not 

 remain in civilized society is that men will exchange it for what 

 is to them more valuable. The miner exchanges it for the neces- 

 saries of life. In New York gold is twice as valuable as in Nevada, 

 and in India fifteen more so than in the placers. The quantity of 

 gold in the world at the time of the discover}^ of America by 



[Ail Inst.] DDD 



