ON THE DEEP BORIXG AT EICHilOND, SURREY. 523 



38. Stjppleme]S"tart Xotes oi the Deep Borixg at Eich^iond, Surrey. 

 By Prof. John W. Judb, F.E.S., Sec. G.S., and Collett Homer- 

 sham, Esq., F.G.S. (Read June 24, 1885.) 



At the time when our former communication to the Society was 

 published (November 188-i*), we were able to report that this very 

 interesting well had, on the 15th of October, reached a depth of 

 1409 feet. "We now propose to chronicle the subsequent progress 

 and termination of the undertaking, adding some new observations 

 which have an important bearing upon the subjects discussed in that 

 paper. 



Subsequently to the date mentioned, many very serious difficulties 

 were unfortunately encountered in carrying on the work ; but, in 

 spite of these disappointments, the Eichmond Yestry, acting under 

 the advice of their engineer, Mr. S. C. Homersham, determined to 

 persevere in their efforts so long as they felt justified in incurring 

 the necessarily large outlay. After many vexatious accidents and 

 consequent delays the work had, by the end of the year 1884, 

 reached the depth of 1442 feet. At this point the Eichmond 

 Yestry, to whose spirit of enterprise geologists are so greatly in- 

 debted for the important evidence afforded by this undertaking, 

 decided that they could no longer incur the responsibility of further 

 expenditure, and gave orders to stop the work. 



The work did not come to an end immediately, however ; for the 

 contractors, Messrs. T. Docwra and Son, with great public spirit, 

 offered to attempt to make further progTess with the important 

 undertaking at their own expense and risk. All their efforts, how- 

 ever, succeeded only in deepening the well to the extent of 5 feet, 

 and the boring was fimally abandoned when it had reached the 

 depth of 1447 feet. The well at the bottom has a diameter of 

 nearly 8 inches, and the lowest cores brought up have a diameter 

 of 4f inches. The weE. is lined to within 80 feet of the bottom. 



Unfortunately, no increased supply of water was obtained by the 

 deepening of the well from 1409 to 1447 feet. 



It will thus be seen that the Eichmond well is actually deeper 

 than any other well in the London basin by 145 feet ; but if we 

 reckon from the absolute level of the Ordnance datum line, it will 

 be found to have reached a point 312 feet lower than that attained 

 by any previous undertaking of the kind. 



Although it was found impracticable to plug the bore-hole at the 

 extreme depth reached, for the purpose of temperature-observations, 

 a thermometer supplied by the British-Association Committee on 

 Underground Temperatures was let down to the bottom and kept 

 there for six days. Boring operations had ceased eleven days pre- 

 viously, and the temperature registered in this observation was 

 76-f° F. The temperature of the air during the time the thermo- 



* Quart. Journ. Geol. See. vol. xl. (1884) p. 724. 



