ECONOMIC GEOLOGY. 93 



by that from the Khasi hills, where no duties were exacted, and still 

 more by that from England. Colonel Hannay states that in 1856 there 

 were '^ only from forty to forty-five persons in the Seebsagar district 

 who understand the smelting and working of iron ores." Most of these 

 however, were probably smiths, not smelters. At the present time the 

 manufacture is entirely abandoned. There are blacksmiths who work 

 with English iron and steel, but there does not appear to be a sino'le 

 smelting furnace from Makum to Golaghat. 



As to the quantity of ore, there is a large amount scattered through 

 the measures, and enough is to be procured with little difficulty to keep 

 any number of native furnaces going. But whether the supply obtain- 

 able in any one locality would be sufficient to feed an English blast-fur- 

 nace is more doubtful. I have not myself seen what could be called an 

 abundant supply an3rwhere. In some places the nodules occur in con- 

 siderable numbers, but not in profusion, and the bands are thin, as well 

 as, I think, of poorer quality than the lumps. 



The ore in the Sub-Himalayan beds is inexhaustible, but the 

 quality is very poor, and the scarcity of limestone in the Naga hills must 

 always be a difficulty in the way of smelting operations on a large scale. 



Alum Shales. 

 The readiness with which some of the pyritous shales from the coal- 

 measures exfoliate is very favorable to the rapid oxidation of the pyrites. 

 Such shales could be used for the production of green vitriol and alum 

 and if any considerable quantity were incidentally raised in the course of 

 mining for coal, it might be found possible to conduct the manufacture 

 on profitable terms. 



Limestone, 



Limestone is very scarce amongst the rocks occurring in the area 

 surveyed. 



( 361 ) 



