ESSAYS 661 



these conditions ; but, although it may be free from organic pollution in the 

 ordinary sense, it will, in all probability, be charged with the undesirable 

 acidity already mentioned. A permanent and unlimited flow can often 

 be obtained on these moorland gathering-grounds quite near to the surface, 

 and the choice lies between this source of supply and the sinking of a deep 

 well which will tap the purer water lying beneath the upper impermeable 

 stratum in the soil, on some other portion of the estate. The latter method 

 involves a heavy outlay for boring the well and lining the bore-hole with 

 iron tubes, and the capital sum which is required for the execution of the work 

 will give considerable food for thought before a decision can be arrived 

 at as to which scheme will be the best to adopt under the circumstances. 



When all these factors are taken into consideration it will be found that 

 better results may be ensured by dealing with the origin of the trouble than 

 by the provision of mechanical means for neutralising at the most a portion 

 of its objectionable effects after they have materialised. In the case under 

 discussion the renewal of all metal pipes and fittings at frequent intervals 

 constitutes a heavy drain on the purse of whoever is responsible for the up- 

 keep of the property, the expense recurring with irritating persistency ; 

 and then even ideal conditions are not obtainable. 



In such a case the most effective remedy which can be adopted is to 

 remove all traces of acid from the water before it comes into contact with 

 any metal, and this can easily be accomplished with little trouble or expense. 

 The process by which the separation can be carried out consists of the fil- 

 tration of the water through broken chalk immediately it is discharged 

 from the pump, and before it passes into the pipe by which it is conveyed 

 to its destination. 



When the supply is drawn from a well it may be necessary to provide 

 a reservoir of suitable capacity for storing a sufficient reserve of water 

 against the needs of the dry season, and a hand or power-driven pump will 

 be indispensable for raising the water. Occasionally the distribution may 

 be effected by gravitation direct from the well if sufficient fall in the land 

 is available ; but, as a rule, the storage reservoir will be required in order 

 to obviate the possibility of overtaxing the supply in the day-time when 

 large quantities are being consumed. 



When an exceptionally large volume of water is drawn daily from the 

 well, the motive power for driving the pump can be obtained from a petrol- 

 or oil-engine, or an electric motor, the capacity of which will be determined 

 by the amount of work which has to be performed, and the period of time 

 during which it can be conveniently operated. It is more advantageous 

 to instal a plant of fairly large capacity rather than a smaller one which 

 needs to be run almost continuously in order to maintain an adequate supply. 

 Less wear and tear will be entailed with the larger plant, and a considerable 

 economy in the cost of labour will be effected. 



If the well is situated on high and open ground, and the normal quantity 

 of water to be raised daily is not excessive, the case can be satisfactorily 

 met by the provision of a windmill, which develops the motive power for 

 operating a force-pump fixed at a suitable level in the well. These wind- 

 mills are in use in many parts of the country, and being quite automatic 

 and self -regulating, they are especially useful for a small house supply. It 

 must be borne in mind, however, that, as the quantity of water which is 

 raised is entirely dependent on the velocity and persistence of the wind, 

 it is most essential that ample storage should be provided, possibly for seve- 

 ral weeks' consumption, or the supply may fail in the summer months just 

 at the very time when an increased demand is being made on the reserve. 

 The apparatus requires very little attention beyond oiling once a fortnight, 

 and an occasional new bucket-leather for the pump. Its appearance is not 

 particularly ornamental ; but this is a point which must be ignored, as it 



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