Mineralogical Description of the Island of Bank a. 91 



Of all the mines that are worked at present, in this district, 

 those of Jebus or Anten are the most considerable ; they are di- 

 vided, according to their situation, into those of the Upper-fur- 

 nace, and of the Lower-furnace; in the former two, and in the 

 latter three large mines are worked at present, besides ten small 

 ones distributed through both districts. 



The large mines of the Upper-furnace district are those of 

 Sungie Tango and Suntay, and of the Lower-furnace district, 

 those of Sungie-Bulak, T ay nam and Seam : the ten small mines 

 of both districts are those of Sunko, Sunyu, Sunsing, Sunwad, 

 Sunwing, Sunliawa, Soktjoy, Tenpo, Assun, and Atshey. 



The first mine, near the southern boundary of the district 

 which 1 examined, was that of Sungie-Bulak, named after a river 

 of the same name ; the ground, in the neighborhood has been 

 worked for nearly thirty successive years. 



As the manner in which the business of mining is conducted 

 on Banka, will be minutely described in the sequel, I shall, at 

 present, only premise, introductory to the description of the ap- 

 pearances which I noticed under the surface, that, in large mines, 

 the ground is perforated by a square or oblong excavation or pit, 

 from which the successive layers are carried out by the workmen 

 until they arrive at the stratum which contains the ore of tin. 

 These strata, as has already been remarked, are all disposed hori- 

 zontally, and, comparatively, at no great distance below the sur- 

 face ; extensive tracts of ground are thus, in many places, worked 

 and exposed in succession. In this place particularly, where the 

 stratum had been found very productive, I observed the remains 

 of a great number of pits, from which the ore had been extracted. 



In the pit on which the workmen were at that time employed, 

 I noticed the following succession of strata: 



On the west side. 



No. 1, Stratum, black vegetable mould, . . 1 foot, 



2. Sand and yellow clay loosely mixed, . 1 " 



3. Black clay, an extensive irregular mass unequal in 



. 6 to 8ft. 



depth, from 



sand 



3 feet. 



On the north side. 



1. Stratum, black vegetable mould, . - 1 foot. 



2. Sand disposed in dark colored clay (irregular), 3 feet. 



3. Black clay, variegated with narrow strata of yel- 



low clav ; irregular massive, . . 5 to 6 ft. 



^ Q it 



4. Coarse sand, . • " • 



3 



On the south side. 



1. Stratum, vegetable mould, • • .1 foot 



