D W PO N D S T ION A ND R F C . S RD A MA TI N , . " ‘ mm or COAL A nmu oc nu n v , j ” or m m w a rn : or 32m GL M ES , I PS LO N D O N LT D . WERNER LAURIE , D EW —PO N D S HIST ORY OBSER"A T ION A ND , EXPER IMENT 0 ' AUTHOR OF O OF OF O " A B B OG A THE ST RY A PIECE C AL , I LI R PHY ' " O U TU INT NAT RE S SECRETS , NA RE " C ETC. HAT , LO N D O N LT D . WERNER LAURIE , 8 ESS X S REE S R D E T T, T AN [All rights reserved" P R E F A C E ALTHOUG H much has been written about Dew - has Ponds during late years , it been written chiefly from a theoretical point of view . Being favoured with a liberal grant from the Government Grant Committee of R the oyal Society, I was enabled to give a ’ three - years course of experiment to the In preparing this book of results for publi cation , I have drawn largely on my papers read before the Research Department of the Royal Geographical Society , the British Asso c iation - , and the South Eastern Union of fi Scienti c Societies , and to those my acknow When I commenced my experiments I had a strong leaning in favour of the theory of the 5 i h wa r R E F A C E replenishment of these ponds by dew, but thl s I was soon led to abandon and, although there is evidence to that considerable condensation takes place into - th high level ponds other has , I submit , little or nothing to do M R I EDWARD A . A T N SOUTH N ORWOOD I" XP M T AND B "AT . E ERI EN O SER ION SECT I ON OF F ORMER POND NEAR CH OLSEY SHEEP WAT ERIN G AT UPPER STA N D EAN CH AN CT ON BU R Y RIN G AND POND R I D D LESD OW N POND SH A MBLED EA N BOTT OM POND W AT ERH ALL POND DITCHLIN G B OSTEL POND STANMER D OW N POND EW E B OTT OM HILL POND UPPER ST A N D EAN POND ROTTIN G DEAN POND SHEEP AT UPPER STA N D EA N POND 1 94 CHAPTER I THEIR AG E AND HI STO RY THE term dew- pond has been applied to - certain high level ponds , the chief charac t eristic is as of which that , a general rule , they do not fail to give a supply of water when other ponds at lower levels have dried - up . The source of the water in low level ponds is apparent . They are fed in general dr i by surface ainage , by brooks and d tches , or by the drainage from a road or high shelving ground around . The sources of supply in these cases are visible , and there, is no doubt as to their origin or their replenishment . In the case , on the other hand, of ponds on high ground, where there are no brooks or ditches , ai and little if any drainage , cert n of them have been found either never to have run dry 9 D E W - P O N D S within the memory of man , or only very occasionally . It has appeared, therefore , to those who have used such ponds , that there must be some means of replenishment which is not recognized in the case of ponds at lower levels , and, as the grass on the high ground around such ponds has been observed in the hottest weather to be thickly covered by dew has after nightfall , it been assumed, although not proved, that the ponds also received a s o deposit of dew, and , with the customary habit of assuming where proof is absent , such ponds , about which the mystery hangs , have ” - come to be termed dew ponds . All ponds - on high ground are not called dew ponds , but there seems to be no agreement as to - what constitutes a dew pond , even amongst those who use the term for some ponds Whilst denying the title to others . I think there are reasonable grounds for believing that certain high-level ponds do owe their maintenance to some other source al than the rainfall , although the rainf l is a 1 0 T H E I R A G E A N D H I S T O R Y fil considerable factor in ling all ponds . The point we have to remember is that rain - fed u ponds at low levels run dry , as a r le , more a r pidly than those on high ground, and this statement has been attested in the past by very many observers , from Gilbert White onward . If this were not a fact , we may assume that the term dew- pond would never have w as arisen , since , as I hold, it invented to describe those ponds whose replenishment w as a mystery, and for whose filling rainfall f alone was seen to be insu ficient . We start , then , with the postulate that certain high level ponds maintain their supply in the driest , hottest weather, long after those in the plains below have more or less completely dried up . Investigators into the subject of high ground water- supplies are rarely at a loss in mountain districts for a solution of the problem before them . As a general rule the higher the ground the more mossy and boggy it becomes . Not only is there greater I I D E W - P O N D S precipitation , but the nature of the rocks is such as to bring about , with the aid of the flora which is encouraged to grow thereon , the prevention of complete percolation and loss of rainfall . And even when the water does not collect into tarns , pools , or ponds , the valleys will generally be found to contain running water near at hand on which to draw for a supply . Where the problem has been to discover the source of supply of water for ancient encampments , we find that , apart from wells , even when springs themselves did not rise within their boundaries , as was did sometimes the case , the occupants not , as a rule , have to go far to find the sought - for and much needed water . Whatever may be the real origin of the d ew - water in ponds , a necessity for such ponds was not felt where the soil was of so retentive a nature as to hold up naturally the rainfall , or where the tilting of under ground strata brought out water by means s a of springs . Or rather , shall I y , no necessity 1 2 T H E I R A G E A N D H I S T O R Y ” w as felt of giving to such ponds a particular name of their own, since the source of their supply was apparent . There was no mystery about the fil ling up of a mountain t am . The stream which ran through many a district would obviate the necessity of making ponds . And where these sources were absent , the surface drainage could easily be diverted to feed such ponds as might be made . But in a chalk district things were different , more especially where the chalk reached a height of over 40 0 feet above the level of the surrounding country, and where no spring would be likely to break out . There is , of course , much comparatively flat chalk m covered country , where natural ponds for , flint by reason of the covering of the y debris , sometimes clayey , and sometimes more or has e less sandy, which result d from the denudation of long- ago existing tertiary beds over the chalk . But the home of the dew pond is on the chalk heights where there are a absolutely no springs , and where the ch lk, 1 3 D E W - P O N D S if left alone , absorbs , or at least allows of h percolation of all the rain w ich falls upon it . It is on the higher grounds of the chalk downs - where dew ponds are found, and it is here also where there is frequently but little debris of lost tertiaries to form a soil of more than a couple of inches in thickness , the turf as a matter of fact frequently resting right on the chalk . In such places it was found necessary to give an artificial puddling to the chalk before a it could be made to hold water . It w s finel - found , too , that y divided chalk proved in the long run as good a materi al for making w as the puddle required as clay itself, and this discovery was no doubt brought about simply by virtue of the necessity of finding some cheaper material than clay , which had generally to be brought from a distance , and dragged several hundreds of feet uphill . It is , though , quite conceivable that the idea of puddling with chalk may have been derived from simple observation of the chalk 1 4 T H E I R A G E A N D H I S T O R Y streams which cut their way through chalk downs . If these had not puddled their own bottoms they would have long since been e swallowed up in the chalk, as inde d we have reason to believe many were , although it is only fair to admit that much of their sediment is brought down from other than chalk a districts , and that their beds cont in a mixture of chalky and clayey ooze .