Chap. VIII.] 



ECONOMIC GEOLOGY, 



163 



Mode of smeltino:. 



and it will not be necessary to do more at present than briefly to refer 

 to one or two peculiarities of local interest. 



The method of smelting is here, as in other places, very simple, 

 and the apparatus used very cheap. The iron 

 produced is of excellent quality, but the quantity 

 is but small. The consumption of English-made iron is large, and 

 is increasing, for not only is the demand for iron increasing, but the 

 amoimt manufactured in the district is decreasing from various causes. 

 The shape and construction of the furnaces vary slightly, but that 

 most generally used is nearly cylindrical, tapering 

 into an irregular 'cone at the top. The furnaces 

 are constructed entirely of red-clay mixed with sand; they constantly 

 require to have the inside renewed by fresh linings of clay, which cannot 

 stand more than three or four days^ working. The height of the furnace 

 varies from 3 to 5 feet, with a diameter of the interior of from 9 inches 

 to 1 foot. The furnace itself at the ground is about 2 feet wide, and 

 tapers sometimes from the ground, sometimes from about ^rd or ^th of 

 the height ; the walls are from 4 to 6 inches thick. The front of the 

 furnaces is for the most part nearly vertical, the back therefore slopes 

 considerably more than do the sides, as shown in the annexed figure. 



Fig. 8. — Section and elevation of native Iron Furnace. 



Form, &c,, of fm-naces. 



giving a section of an iron furnace at Chaindanumgalum, in the Namkul 

 Taldq. (Fig. 8) . In some cases,, however^ the furnace is a regular cone. 

 V (375) 



