444 



REPORT — 1895. 



[Fig. 3. 



-JjCTWff rods 



"Sedwieru. (zd>e/ 



Returning now to my narrative of events. When it was decided, in 

 1878, to put down a test hole at Ware, it was anticipated that the Gault 

 there would have been passed through before the Turnford boring had pro- 

 gressed very much beyond its then depth of 836 

 feet, in which case the latter could have been dis- 

 continued if the Ware site proved unfavourable ; 

 for it was obvious that if the Lower Green Sand 

 did not yield water at the more northerly of the 

 two points, it would not do so at the other, which 

 was so much farther from the outcrop. But delays 

 occurred. Soon after starting, the boring-rods broke 

 in consequence of a fall of gravel from above ; the 

 core-tube and a core- extractor were dropped to 

 the bottom, and the guide-pipe at the top was 

 carried away. This necessitated the sinking of 

 cast-iron cylinders, 6 feet in diameter, to a depth 

 of 30 feet from the surface, by means of compressed 

 air ; a work that occupied some time. Later on, a 

 rod became bent near the bottom of the hole at a 

 depth of 780 feet, and much time was lost in re- 

 covering the crown and tubing which were set fast 

 by this accident. Thus the work occupied much 

 more time than had been expected, whilst at the 

 Turnford boring, the contractors (Messrs. Docwi'a 

 & Son), after reaching a depth of 896 feet, adopted 

 the diamond drill, and in this way hastened the 

 completion of their work. Whereas the boring by 

 chisels had been proceeding through the Gault clay 

 at an average rate of about 2 feet in depth per 

 week, by the new process an advance of 18 feet or 

 more was made in the same time. Thvis it even- 

 tually happened that the Gault was pierced through 

 at both places at about the same time. 



Shortly before this, a boring made at Crossness 

 for the late Metropolitan Board of Works had 

 shown that there was no Lower Green Sand in that 

 locality ; whilst at Tottenham Court Road, Messrs. 

 Meux had bored through 64 feet of what was at the 

 time erroneously supposed to be Lower Green Sand, 

 and had found it to be a comparatively compact 

 stone, containing but little water. These facts were 

 discouraging, but they still left room for hope that 

 the thinning-out of the water-bearing stratum was 

 confined to the deepest part of the London basin. 

 The results of the New River Company's borings 

 were, therefore, looked for with great interest, and 

 when, in May iS79, Silurian rock was struck at a 

 depth of 796^ feet at Ware, and, a month later, 

 Devonian was found at a depth of 980| feet at 

 Turnford, those who took a scientific interest in the question, naturally 

 tried to secure all the information obtainable under these exceptionally 

 favourable circumstances. Hence the demand for a special inquiry as to 

 the direction of the dip of these rocks. 



CcT^tujbe' 



-Crofrrv 



Scale, 1 in. to 8 ft. 



