OOOUEEBNOES OF COAL. 207 



abandoned in 1813 or 1814. Some years afterwards it was resumed, and in 1827, 

 according to Mr. Clowes, the agent, 20 men and 5 boys raised about 4,400 tons of 

 coal, coarse and fine. But the work was again abandoned not long after, and not 

 resumed till 1847, when the mine was opened by the Portsmouth Coal Company, which 

 has also ceased operations there. Mr. Barbour speaks of the amount of coal and 

 rock, "principally the former," that has been excavated at this place, as about 

 100,000 tons. 



Three beds were discovered at this place, "all of workable width." Dr. 0. T. 

 Jackson says that the bed last wrought was 13 feet thick. He states its strike to be 

 S. 80"^ W. and E". 80<^ E. ,• dip, 35^ southeasterly. Mr. Clowes, however, says that the 

 beds run l^B, and SW. and dip from 40° to 90*^ southeast. As the mine is now 

 un wrought, I could not settle these points. 



14, The Aquidnech mine, — [In the account of this mine it is stated that three 

 beds of coal occur, only one of which, from 2 to 20 feet thick, was worked by the 

 Aquidneck Coal Company. The middle bed was followed down to the depth of 620 

 feet, from which six gangways were extended, from 80 to 844 feet each. During the 

 last half of 1851, 3,100 tons of coal were taken out, and an opening made into a sub- 

 jacent bed. — J . B. w.j 



15. In Newport^ Rhode Island, — [An outcrop of coal in the southeast part of the 

 town is described, and it is stated that during the Eevolutionary war the British 

 made excavations at this spot in search of fuel. The prospect is poor. The shale 

 abounds in coal plants. — Abstract by J. B. W.] ^ 



Other references to coal will be found on pages 169, 182, 189, 190, 198. 



SEARCH FOR COAL. 



As the coal beds in this basin are mainly concealed in depressions 

 filled with drift, or have their ontcrop under river beds and swamps, the 

 details of this report are mainly useful when made the basis of a process of 

 exclusion, in which the prospector searches along lines of strike between 

 bands of strata which are shown to be barren. So far as can be ascer- 

 tained from field evidence, coal beds are likely to be found in the greater 

 part of the field outside of the red rocks and lenticular areas occupied by 

 the upper conglomerates, which together do not occupy an area greater 

 than 30 square miles. In most of the area thus left, the dip of the beds is 

 low, so that experimental borings are likely to penetrate several strata. 

 Where the strata stand at a high angle the chance of meeting with coal 

 beds is less good, although they may exist at one side of the trial boring in 

 the same field. Such a belt of highly inclined strata runs north-northeast 



^ Mass. House Documents No. 39, March, 1853, pp. 9-13. 



