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NOTES ON SOME RECENT DEEP BORINGS FOR 

 WATER AT BELFAST. 



By Robert Young, C.E., J.P. 



When near the end of the i8th century geology began to 

 take its place as a science, it was largely indebted to the miner 

 and the well sinker for the observations and facts on which its 

 conclusions were founded, and since then vast additions have 

 been made to its stores by the labours of engineers in their 

 deep excavations for railways, docks, canals, waterworks, and 

 sewers, not to omit the tunnels driven through great mountains, 

 such as Mount Cenis and San Gothard. Lately, the trial shaft 

 sunk on the Enghsh side for the intended channel tunnel, led 

 up to a deep boring being made at the suggestion of Prestwick. 

 Coal was found below the chalk, and it is the opinion of 

 practical men that it can be raised and sold at a good profit 

 even at such a depth. The Marquis of Downshire's search for 

 coal at Carrickfergus led to the discovery of the important 

 beds of salt rock. However, I wish to confine my remarks to- 

 night to a comparatively limited area and to borings, nearly all 

 made quite recently for water supply. These have been generally 

 sunk by the Diamond boring apparatus which works admirably 

 in solid rock of any degree of hardness, from sandstone to 

 granite or porphyry. The boring tool is just an iron tube, 

 into the lower edge of which are firmly fixed coarse diamonds 

 which are mostly the refuse of the South African mines, and 

 as the tube revolves an annular track is dug out corresponding 

 with the section of the tube, i.e. a 6 inch tube, having | inch 

 thickness, cuts a ring | inches by 6 inches, leaving a core of 

 rock \\ inches diameter. This is broken off in pieces 5 to 6 

 feet long and brought to the surface showing the character of 



