RILLS. 



ing it to towns and villages, in dry or other fituations where 

 it is fcarce. See Irrigation, Watering of Land, and 

 the following article. 



RlLLs, Artificial, fuch as have been formed or made by 

 means of art. It has been remarked, that the practice of 

 conltrudting rividets of this fort for fnpplying water is pe- 

 culiar to a few diftricls of this country, as Yorkfhire and 

 weft Devonfhire, in the latter of which they have been 

 made ufe of time immemorial in bringing wh.it, in the {imple 

 language of the diifrict. is termed " pot-water" to the 

 farm-hcufes, and the hamlets of cottages in upland fituations ; 

 an excellent expedient, which is fuppofed applicable in many 

 other parts of the ifland, but which, except in tin- cafe of 

 Yorkfhire, has hitherto been confined to that extreme part 

 of the country. 



And in forming thefe forts of rills in their original diftrift, 

 it is obferved by Mr. Marfhall, that one which fupplies the 

 houfe with water, alfo a drinking-poo] near the yard, and 

 in the natural courfe of it conveying it through a ftraw 

 yard, a trough is placed acrofs it for the ufe of the yard 

 cattle ; and which has, likewife, been for a vaft length of 

 time led over fom- grafs land, which lies below the yards, 

 on the principle of the float and drain. But that although 

 this rill is feldom, if ever, dried up, leading it along the fides 

 of the valley, through upland inclofures, which are deftitute 

 of water for ftock, and their value of courfe thereby much 

 depreciated, does not appear to have been thought of. In 

 the courfe of the fuminer of 1792, being delirous to know if 

 this rill could be carried through an intended fuite of yards 

 on the fide of the valley, he took the level, and found not 

 only that object to be attainable, but alio that it might be 

 led with cafe into two waterlefs fields which lie above thefe 

 yards ; and, through them, into four or five more (equally 

 in want of water for flock) fituated beyond them. It is 

 added that, in afcertaining thefe facta, he made ufe of a 

 mafon's long level inverted, a plummet-hole being previoufly 

 cut in the head of the ftandard ; the crown of which being 

 fet upon the ground, the arms of the level were fteadied by 

 rods in the horizontal pofition ; and a carpenter's rule held 

 acrofs another rod, fet up, at as great a diftance as a clear 

 fight would admit of, and at a height upon the ftaff equal 

 to the height of the level. Finding this a molt (imple and 

 perfect initrumeut, but difficult to adjull, by reafon of its 

 111 liability, he has iince had a frame-hvel made on the fame 

 principle ; namely, with a llraight edge, or top rail, anfwer- 

 ing to the bafe -board of the long level, with a broad piece 

 falling dou n from the middle of it, anfwering to the ltandard ; 

 and with two end-pieces or legs, to fuperfede the ufe of the 

 rods, together with a bottom rail, eight or nine inches from 

 the ground, and with diagonal braces to keep the whole- 

 firm, and prevent the middle or plumb-line from getting out 

 of the fquarc with the llraight edge of the top rail ; which 

 is feven or eight feet long, and the height about four feet. 

 He thinks that half a rod long, and a quarter of a rod 

 high, are eligible dimenfions when great accuracy is required. 

 But a (horter length, as one-third of a rod, is more handy. 

 And, as an improvement of the rule and rod, he has con- 

 trived a crof -ftaff '; namely, a flip of thin deal, about five 

 fei : and a hall long, with a crofa-piece about two Feet long 

 and tine'- inches wide, fixed in the edge of it, at the exact 

 height of the level; the top of the Itafl riling twelve or 

 eighteen inches above the upper edge of the crow-piece, that 

 the hand of the perfon who holds it up may not interfere 

 with the view. This crofs-piece (hould be of white wood, as 

 .leal, or be painted white, that it may be more dittinCtly 

 t a diftance. With this implement the flowing level 

 may be well afcertained. 

 Vol. XXX. 



And it is obferved that, in order to afcertam the proper 

 fall of a rill of this intention, he previoufly took the run- 

 nn.g level of the ancient floating kat of the meadow, and 

 finding its fall irregular, he took it in two places where the 

 variations were greateft. In the firft, the fall was twenty, 

 feven inches in one hundred and ten feet ; which is nearly 

 one inch, or one foot of fall to fifty inches, or fifty feet, in 

 length. In this part the current is in a degree rapid ; the 

 fall much too great for the general intention. The fall in 

 one hundred and ten feet of the other part is barely fix 

 inches ; which is only one meafure of perpendicular height 

 to two hundred and twenty of horizontal length. But in 

 this part the motion is too fluggifh ; the furface of the 

 water is nearly fmooth ; barely d'impling ; no ripple or agi- 

 tation appears. The fall is evidently too little for a water 

 courfe, in which there is not a constant ftream. He has 

 therefore fixed upon one meafure in a hundred, as the 

 proper fall of a water-courfe, into which water is occa- 

 fionally thrown for the purpofes of watering lands, filling 

 drmking.pools, citterns, and other fimilar purpofes. And 

 in order to adjuft the level to this defcent, he meafurcd one 

 hundred feet in length, and having nicely afcertained the 

 dead level, he deprefled the range of the top bar one foot 

 below the upper edge of the crofs-piece of the ftaff, and, 

 while in that pofition, he marked the lituation of the 

 plumb-line on the face of the level, the plummet -hole being 

 made wide for this purpofe ; thus fixing the flowing level. 

 And with this defcent, he has traced a line from an intended 

 refervoir, and from point to point, through the fields of one 

 fide of the farm, and finds that it reaches, even vvith this 

 defcent, within every field; and that three-fourths, or a 

 larger proportion, of the furface are capable of being 

 floated from this intended pool. With the view of feeing 

 the actual motion of water falling one in a hundred, he has 

 had fifty yards of the upper end of the line opened, and finds 

 the current fully fufficient ; a lively rippling ftream, more 

 active, perhaps, than is neceflary. But the leakage being 

 the lefs the quicker the water moves, it may, he thinks, be 

 fafely concluded that one foot of fall in a hundred feet 

 length is nearly the proper degree that is required. 



And in the fame cafe he has, by the fame means, alfo 

 found that, from a fimilar refervoir formed near the fource 

 of the rill, water might be conveyed to every field, and 

 almoft every acre of the oppofite fide of the farm, which 

 is a matter of great confequence. It is fuggefted, that the 

 ufes of thefe refervoirs will be thofe of having in readinefs, 

 during the fummcr months, when the rill is weak, a body 

 of water to throw into drinking-pools, citterns, &c. ; a weak 

 current turned into a dry trench is abforbed by its per- 

 forations and fiftures, for fome time, at leaft, after it is 

 turned in ; whereas a body of water, rufliing quickly along 

 it, not only in part efcapes abforption, but tends to till up 

 the leaks ; and, in winter, thefe refervoirs will be uleful in 

 fcouring the trenches, and in hoarding up bodies of water 

 for the purpofe of irrigation, or other fimilar ufes. In the 

 letting out of thefe rills, he has laid the head or upper end of 

 each, from two to three feet below the intended furfaces of 

 their refpeftive refervoirs, when full. Hence, by the means 

 of a portcullis flood-gate, a body of water two or three 

 feet deep, and the whole extent of the furfaces of the 

 bafons, may be poured into the rills, fatter or flower, as 

 may be requilite. And in a fubfequent minute it is Hated, 

 that difficulties were met with in conducting a rill through 

 an open grove of trees, but which were overcome in the 

 following manner ; having, In | the frame level and 



crofs, afcertained the general defcent, or flowing level, 

 through the whole extent of the grove ; and having, in flu' 

 N n operation, 



