AMERICAN INSTITUTE. 549 



gutters, so arrang>;d that numerous streams of air, or of steam, or 

 of vapor of water, shall be forced into and through the melted 

 iron as it flows from the blast furnace. 



The common process of refining the iron by using the refinery 

 furnace, is done with. Where persons still prefer remelting for 

 refining, then Martien's process is still used, as the melted iron 

 flows li'om the furnace to the moulds. This gutter, or channel, 

 may be made of any suitable material, but cast iron is best, the 

 bottom part being hollow, in order to receive steam, or air, or 

 both. This gutter, or channel, is perforated with numerous 

 holes, which should be inclined, so that the streams of air or 

 steam may be forced through the melted iron as it flows, in an 

 oblique direction, but preferably forced into the iron in the direc- 

 tion in which it runs. However, it may be forced in sideways, 

 from below or opposite to the flow. When hot blast or cold blast 

 are used, it is best to connect the hollow bottom of the gutter, 

 with the air pipes used for supplying the bl.ist, and when steam 

 is employed, the hollow bottom of the gutter is connected with 

 the boiler used. By these means the air or steam introduced into 

 the hollow bottom of the gutter, below the melted iron will be 

 forced through it in numerous streams. The gutter may be cov- 

 ered over for any part of its length, and so arranged that heat 

 may be applied to it, and so of the moulds or beds, that heat 

 may be applied to the iron after leaving the furnace. The iron 

 so purified may be allowed to cool in the moulds, or it may be 

 run into a reverberatory or suitable furnace, to be highly heated 

 therein, and it may be puddled in the usual way. 



Martien is aware that it has been heretofore proposed to use 

 streams of steam in puddling, and refinery furnaces, in such 

 manner as to come in contact with the surface of the melted iron, 

 and it has been also proposed to introduce steam below it when 

 puddling. But Martien claims the purifying of iron from a 

 blast or a refinery furnace, while still melted. 



DECIMAL WEIGHTS AND MEASURES. 



THE FRENCH METRICAL SYSTEM. 



The London Mechanics' Magazine of October, 1856, contains 

 a valuable article on this subject, worthy of our attention. 



Habituated to the idea that in the revolution '/ranee has 

 achieved a perfection in her weights and measures, by referring 

 as a basis of infinite accuracy to the metre, or 07ie ten millionth part 

 of the arc of the meridian from the equator to the pole. 



The plan of a natural standard originated with the never to be 



[Am. Inst.] 36 



