THE HOUSE AND ITS EQUIPMENT. 



Il(). GENTLE DEPRESSION 7 



Londo n c lay, 



chalk, and such 



between a well 



water. That at M 



the success might 



local conditions 



from &quot; Woodward s Geology 



be carefully kept of 



is the 

 r may 



and e 

 faultin 



at X and one 

 would need 



be greater 



Fi 



115 

 ol 



CAUSED i!Y EASY PUMPING. 



to the chalk beneath. Deep chalk is often comparatively waterless. But the term waterless has not 

 so much significance when a single house supply is involved, for it is a poor supply indeed that will 

 not find water for a large house in a day of eight hours pumping. Often a careful examination 

 of a district will show some peculiarity, such as a geological fault, which renders a successful well 



possible only a few yards 

 distant from an unde 

 sirable situation. An 

 example of a geological 

 fault is shown in Fig. n_| 

 on the right, where, as 

 recorded by Mr. Whitaker, 

 the chalk is faulted 

 upwards so as to abut 

 against the basement bed 

 of the London clay. The 

 beds a, b, c, d are the 



Reading clay. Here at Bennets End they are level with the 

 make all the difference between early success or failure, as 

 at M, for that at X would soon reach chalk and might obtain 

 to go much deeper to reach the chalk, but when it did do so 

 than in the case of boring at X, depending, of course, on other 

 shows a characteristic section across country at Snettisham 

 England and Wales.&quot; When any well is bored records should 

 the material passed through and the distance from the surface. In time such 



records accumulate evidence that may solve some hidden mystery in geological science. Every bore 

 hole not so recorded has failed to be of the fullest possible sen-ice 1o the country generally. 



In conclusion, it may be repeated that the maximum of safety and the minimum of cost are usually 

 to be obtained with a bored tube well. The elaboration and greater magnificence of the dug well is only 

 obtained at a greatly-enhanced cost and a serious risk of pollution. There is, of course, no very imminent 

 risk if a dug well be made in clay simply to enable a pump to be placed within reach of the- water in a 

 bore-hole put down al the bottom of the well. In such case s the bore-hole is to be hermetically sealed 

 to the pump suction, and the dug well is merely a dry pump chamber, the bottom of which is proofed with 

 concrete and the sides are clay behind the lining. Serious cases of pollution have, however, occurred 

 where a well, bored in the bottom of a dug well, has been left with its lining pipe standing up open in the 

 dug well. Water has entered the dug well and risen over the open top of the tube. The tube should 

 therefore always be 

 closed and directly 

 connected to the 

 pumps, so that, 

 even if water 

 should collect in 

 the dug well, none 

 of it can be drawn 

 by the p u in p s . 

 Pumps in dug wells 

 ought never to be 

 drowned, that is, 



should never be exposed to be covered with water collected 

 be had it may pollute the pump water by its contact with 

 water is almost invariably safe, because it has been well 

 earth s surface. Plant roots seem to have much influence 

 doubt also that water becomes thoroughly oxidised in 

 earth. Every change of the barometer causes influx or efflux 

 of the pores of the rocks. But, strange to say, living 

 artesian wells. This has occurred in France and once in 

 country, where a well was bored on a hill to the depth 



1 17. - HEAVY DEPRESSION 



CAUSED BY PUMPIXG HARD. 



in the dug well, for if such water 

 the pump glands and rods. Artesian 

 filtered in its passage through the 

 in this direction, and there is no 

 passing downwards through the 

 of vast volumes of air into or out 

 creatures have been brought up from 

 the writer s experience in this 

 of the nearest valley. The rocks 

 the bore-hole had doubtless travelled 



were hard, blocky and much fissured, and the water to 

 from the valley stream horizontally to the boring through the wide fissures. Though such cases 

 will be rare, it is always desirable to remember their possibility. It is probable that in the 

 instance named a deeper boring would have obtained water free from life, for living creatures 

 would not descend far. Even where there is much pollution of the surface water this need 



