QUARRY. 



profperity and convenience ; contributing largely to the 

 carrying on of different forts of works and improvements. 

 Without them much iifcful labour mull be Arholly at a Hand; 

 a variety of necefTary burinelles be incapable of being car- 

 ried on ; and the eflefts of it upon various arts and manu- 

 faftures, be much too ferious to be thought upon. In 

 fhort, the numerous fiibilances of different kinds, whicii are 

 taken from the bowels of tiie earth in this country, con- 

 ftitute one great fource of our national wealth and pro- 

 fperity. 



Qi;.\RRIEs, Pits, &c. Draining of, the proper, mofl; 

 convenient, and appropriate means of rendering all fuch forts 

 of works dry, free from water, and in a fit flate to be 

 wrought with eafe and advantage. In the effedtual per- 

 formance of all kinds of undertakings of this nature, there 

 is occallon for the application of the fame principles, which 

 are fpoken of and explained in confidering the nature of 

 draining land in general, and the particular manner which 

 is necellary to be purfued in the praftice of fpring drain- 

 ing. See Draining of Land, and Si'RiHG-Draining. 



There can be no doubt, indeed, but that the having re- 

 courfe to fuch principles, and the modes of praftice refult- 

 ing from them, will be equally expeditious, beneficial, and 

 fuccefsful, as well as in many fituations of very material 

 importance, in the various cafes of this fort, as in thofe which 

 have been mentioned ; by leading to and introducing the 

 moll ready and eafy means of diminifiiing the quantities 

 of water, which are frequently met with in the courfe of 

 working them, and which not unfrequently obllrutl and 

 hinder in a very high degree, but fometimes wholly put a 

 flop to the work which is carrymg on in them. Such, at 

 leall, is very often the cafe in quarries of the free-ilone, 

 lirae-ftone, flag-ftone, marie, and other kinds, as well as in 

 pits of the coal and other forts. The want of this fort of 

 knowledge, of courfe, is one great caufe why fuch a 

 number of quaiTies and works ol that kind, in different 

 parts, often lie altogether, or for a great length of time, in 

 an unwrought ftate ; which might otlierwife be wrought to 

 very great advantage. 



As it is now well underftood, that mofl fprings and fub- 

 terraneous coUeclions of water are formed and fupplied 

 from fuch grounds or lands as lie higher than that of the 

 places where they are found or met with, which, on ac- 

 count of their being of an open or porous nature, jdmit 

 that of rain and other forts of moifture to filtrate and pafs 

 freely through them, which finking and defcending to very 

 great depths, through fuch open materials of the rocky, 

 Tandy, gravelly, and other loofe qualities, before it becomes 

 impeded and obllrudled by fome fort of impenetrable ilra- 

 tum or layer of an earthy or folid ftony na-ture, fuch for 

 inflance as thofe of pure iliff clay or compail rock ; it may 

 happen, that in many fuch cafes, in finking pits or (hafts 

 for ftone, coal, or any other kind of fubterraneous material 

 near the bottoms of hills or high grounds, beds of quick- 

 fand will be met with, and dug into, which are fo hill of 

 water, that to pafs through them becomes a mofl trouble- 

 fome, difficult, and expenfive piece of work, and fome- 

 times inipoffible to be performed, but which, from knowing 

 that the water proceeds from the porous ground that lies 

 above, it may often be prafticable to intercept and cut off 

 the greater part of the water, before it reaches fuch fand 

 beds iu the quarries, pits, and fliafts, by the means of 

 boring into and tapping the water at the tail of the banks 

 of this nature, provided that the ground naturally declines 

 lower than the place where the fand is found in the quar- 

 ries, pits, iic, and the whole or moft of the water be 

 (drawn off, and diverted from them at a coraparativelv 



Vol. XXIX. 



trifling expence to that which is employed as the commoa 

 remedy in fuch cafes and circumftances. 



In order to accomplifli this intention, it will be necefTary, 

 in afcending from the quarry or pit, to carefully examine 

 and afcertain, if at any place higher on the declivity, any 

 porous ftratum, bed of rock, fand, or gravel, laiis out, 

 which may condudl and convey the water contained in it 

 to the fand bed, which is below in the works ; and where 

 any fuch bed is found, to cut or bore into it in fuch a 

 manner as to form a drain, that is capable of carrying away 

 the whole or the greatefl part of the water, and of 

 courfe to clear, or diminifli the quantity contained in the 

 quarry or pit, which would otherwifc have continued to 

 defcend through fuch porous fubflrata or beds, and have 

 continued to fill the fands, or quarries and pits. 



But although this part of the bufinefs may have been ac- 

 complifhed, and the fupply of water from the higher ground 

 entirely cut off, a fufficient quantity to injure, hinder, and 

 inconvenience the working of the quarries or pits, may yet 

 continue to drain and ooze from the fides of the fand beids, 

 notwithflanding they fhould happen to dip towards the 

 lower ground, in which cafes, however, that water may 

 readily and with great eafe be commonly drawn uff at fome 

 particular point in it. 



In order to effeft this, and thereby remove the incon- 

 venience of this filtrating water, in defcending from the 

 quarries or pits along the declivity, it (hould be endeavoured 

 to difcover and afcertain, at what particular point or place 

 in the low ground, the fand terminates or tails out, which 

 is moflly befl accompliflied by means of proper levelling ; 

 and if there fhould be there any appearance of the waters 

 having a natural outlet, it may, by means of making in it 

 a deep drain, be far more readily and efleftually drawn off 

 and removed ; as fprings, for the mofl part, naturally paf» 

 and flow through narrow, winding, convoluted openings, 

 or perforations ; of courfe, whenever the orifices or paflages 

 arc opened, enlarged, or made lower than before, the dif- 

 charge of water becomes greater and more expeditious. 

 Where, however, there happens to be a deep imper- 

 vious layer or covering of clay, or other matter of a 

 fimilar nature, placed alcove or upon the termination or tail 

 of the fand, the dram need only be cut down to it or a 

 little way into it, as by means of boring through it, or the 

 remaining portion of it, a ready and eafy outlet or pafTage 

 may be given to the whole of the water, that may be con- 

 tained in the fand-bed or other porous flratum. 



This mode of draining quarries and pits may often be of 

 great utility, advantage, and convenience, as it will alfo, 

 in a great degree, remove, or at any rate relieve, the 

 trouble and difficulty that would afterwards have attended 

 the finking the quarry, pit, or fhaft ; as the water thus 

 drawn or cut off, mull of neceflity diminifh and reduce the 

 quantity, which would have been found at a greater depth, 

 the fame body of it probably palling downwards from one 

 ftratum to another, as far as they continue to be porous, or 

 capable of .idmitting it. Therefore, it is of very material im- 

 portance to drain and lay dry all fuch ground as is fltuated 

 higher, but contiguous to quarries, pits, or other deep fubter- 

 raneous works of the fame kind, for the above ftated reafons. 

 And it may, in general, be accomplifhed with but little 

 ti^uble, difficulty, or eiipence, by adopting the fame prin- 



tlQl 



cfl 



c^les, and the fame means. 



But in regard to the removal of the water found and con- 

 tained in the bottoms of fuch quarries, pits, or deep workt, 

 it mull be drained oft and got rid of in quite a different man- 

 ner, as the level of the ground may probably be, or declinCj 

 nowhere lower than the mouths or openings of fuch quarries, 



F f ' pits, 



