84 GEOLOGY OF THE NARRAGANSETT BASIN. 



As to the first of the aforenamed uses, it may be said that the coal 

 of this basin seems to be fairly well suited to the needs of smelting. 

 It is low in sulphur; its specific gravity is so high that it will give a 

 large number of heat units for a given bulk; the ash, though high, is, 

 owing to its composition, easily smelted. I was told by the person who 

 owned the mine at Portsmouth the greater part of the time during which 

 it was worked, that the coal was the best that could be obtained for 

 smelting copper ores as well as for the subsequent working of that metal. 

 The further statement was made that a cargo of the fuel had been sent to 

 an iron furnace on the Hudson and that it proved very satisfactory as com- 

 pared with the anthracite of Pennsylvania in making Bessemer pig. I was 

 also informed by one of the Crocker Brothers of Taunton, Massachusetts, 

 who worked the mine, that a test of a few tons of the coal had been made 

 in the manufacture of water gas and that it was well suited to the purpose. 

 It is not now possible to verify these statements, but they appear to be quite 

 consistent with what is known of the nature of the anthracite of this field. 



The only undetermined qualification of the Narragansett coals as 

 regards their use, in the special arts above mentioned is that observed by 

 Dr. Arthur B. Emmons and described in the paper referred to. This, in 

 the words of the author, is " the striking peculiarity (hitherto unnoticed in 

 anthracite coals, or, I believe, in any coals) of quickly taking up a large per- 

 centage of water under a moist condition of the atmosphere and as readily 

 parting with it under a drier condition of the atmosphere." According to the 

 records obtained by Dr. Emmons and his collaborator, Dr. F. A. Grooch, the 

 Narragansett coal may, with the changes in the humidity of the air, vary as 

 much as 15 per cent of the whole weight of the material. How far this 

 peculiarity may affect the value of the coal in the smelter or water-gas 

 converter will have to be determined in an experimental way. 



In considering the prospective value of this coal, the cost of mining it 

 is of course a matter of much importance. So far the practical experiments 

 in mining have been too few and too imperfectly executed to afford any 

 clear determination. The mine at Portsmouth, the only one in the basin 

 maintained in operation for any considerable time, was not well managed. 

 As the deep part of the pit was almost absolutely dry, the little water found 

 in it entering from the old upper workings, there was but slight expense for 

 pumping, the drip collected in the sump being hauled about once a month 



