WATER. 



mills are fituated in the valley below the great dam, the 

 water being conveyed to the wheels by channels coming 

 through the dam, and conveyed away into a large tail bafon, 

 which is tlie original courfe of the river. The wheels, 

 which are very numerous, are all 22 feet diameter. They 

 are placed in f^iveral different mills, for rolling and forging 

 iron and copper, boring guns, making anchors, &c. Thefe 

 mills are arranged on the fides of the tail bafon, which is 

 navigable to bring the boats up to them. There are alfo 

 two larL^e faw-mills at the end of the femicircular channel. 



Thefi- works are very complete, owing to the excellent 

 execution of the dam and water-works ; but it is not a good 

 plan to place the mills beneath the dam, becaufe if it fhould 

 fail, or the water pour over it by an extraordinary flood, 

 the mills and buildings below would be in danger of being 

 carried away ; whereas, on the other conftrudlion, the mills, 

 being placed at a diftance from the river, are perfedlly fafe, 

 and would not be injured if the (dam ihould be wholly carried 

 away. This is not a fault imputable to the gentlemen we 

 have mentioned, as the foundations of thefe works were 

 commenced in the time of Peter the Great, and too far ad- 

 vanced to admit of altering the plan radically, when the em- 

 prefs Catherine invited Mr. Gafcoigne to Ruffia, in 1786, 

 to enlarge them to their prefent magnitude. 



On the Dijlribution of the different Falls of Water In Rivers. 

 — In erefting a mill, care mull be taken to place it fo that 

 it (hall not be impeded by flood-waters, except when they 

 rife to excefs. When the water below will not run off 

 freely, but (lands penned up in the wheel-race, fo that the 

 wheel mud work or row in it, the wheel is faid to be tailed, 

 or to be in back water or tail water. 



Upon moft rivers in this country all the falls of water are 

 fully occupied, and at every mill there is a weir, which pens 

 up the water as high as the mill above can fuff'er it to 

 ftand without inconvenience. Each miller is anxious to ob- 

 tain the greateft poffible fall, and he can at any time aug- 

 ment the fall, by raifing the furface of his weir ; but as this 

 may produce an inconvenience to the mill above, in prevent- 

 ing the water from running freely away from its wheel, it 

 is a conftant fonrce of difpute and litigation. A mill may 

 be fubjedled to tail-water by the concurrence of fo many 

 circumftanccs, that it is frequently very difficult to know 

 where to feek the beft remedy, whether the miller ought to 

 raife his wheel higher and diminiih his own fall, or infill 

 upon a diminution of his neighbour's below him by lowering 

 his weir. 



The following rule is that which Mr. Smeaton conRantly 

 followed, in placing fucceffive dams upon rivers, whether 

 for the ereiSlion of mills or for navigation. In flat countries, 

 where the falls of water are fmall, and confequently tail or 

 back water is moft troublefome, thofe dams muft be fo 

 built, that no one fliall pen the water into the wheel-race of 

 the mill next above it, when the river is in its ordinary fum- 

 mer's ftate. The fame rule we have found generally fub- 

 fifting in ancient mills. 



This rule is founded upon reafon ; for if the ereftion of a 

 dam does not affeft the mill above by tail-water, in dry fea- 

 fons, when water is the moll icarce, it can do no material 

 injury at any other time. Every mill that is well and pro- 

 perly conllrufted will olear itfelf of a confidcrable deptli of 

 tail-water, provided it has at the time an increafe of tlie heiglit 

 of water in ilie mill-dam or head, and an unlimited quantity 

 of water to draw upon the wheel ; for if floods produce tail- 

 water, they alfo increafe the head water, and alford a fupe- 

 rior qiiantity to be expended. This is the proper means by 

 which a number of mills on the fame river are to be cleared 

 of back-water, as far as is confident with the mutual enjoy- 



ment of their feveral falls of water. This alone is a very 

 fufScient fectirity againft any one being injured. Common 

 breaft-mills will bear two feet of tail-water, when there is 

 an increafe of head, and plenty of water to be drawn upon 

 the wheel, without prejudice to th^ir performance ; but 

 mills well conftrudled, vith flow moving wheels, will bear 

 three and even four feet and upwards of tail-water. Mr. 

 Smeaton mentions having feen an infl;ance of fix feet ; and it 

 is a common thing in level countries, where tail-water is 

 moft annoying, to lay the wheels from fix to twelve inches 

 below the water's level of the pond below, in order to in- 

 creafe the fall of water ; and, if judicioufly applied, is at- 

 tended with good effeft, as it increafes the diameter of the 

 wheel, and though it muft always work in that depth of 

 tail-water, it will perform full as well, becaufe the water 

 ought always to run off from the bottom of the wheel, in 

 the fame direftion as the wheel turns. 



The law refpefting mill property is by no means fettled, 

 but is greatly influenced by the cullom of the mills upon any 

 river or in any diftrift ; fome few points however are eftabhflied. 

 Every one has a right to that fall which the water has, in run- 

 ning through his own grounds, and may make what ufe he 

 pleafes of the defcent of the water, provided that he does not 

 divert the water, at the tail of his eftate, into any other chan- 

 nel, or that he does not pen up the water higher than the 

 level at which it has always entered into his land ; he has alfo a 

 right to infift that the miller below fhall let the water depart 

 from his grounds, at the fame level at which it has always been 

 ufed to do. The knowledge of this is very neceflary, be- 

 caufe a miller very frequently finds himfelf ferioufly injured, 

 when he is not entitled to any redrefs. It fcarcely ever 

 happens that any confiderable improvements or alteration in 

 mills can be made, without producing difputes among the 

 parties interefted. Suppofe, for inftance, that there are 

 two ancient mills upon a river, with an unoccupied defcent 

 in running over the lands between them, the proprietor of 

 this land, by deepening the channel and erefting a weir, may 

 bring all the fall into one place and ereft a mill, without in- 

 fringing the conditions we have laid down ; but ftill the 

 miller below him may be confiderably injured : for in the 

 original ftate the river, in running down with a regular and 

 eafy flope, from the upper mill to the lower, held a great 

 quantity of water, which was a corps de referve for the miller 

 below, and tended to regulate his fupply. If the upper 

 mill ftopped working, the water contained in the river would 

 ftill run down to him, and fo long as that laftcd he could 

 continue to work, perhaps until the upper mill began to 

 work again, and thus he would fufFer no interruption. The 

 erection of an intermediate mill cuts off this refource, and 

 he will be obliged to ftop working very foon after the new 

 mill ftops working ; and further, he is obliged to work 

 when the new mill is at work, or elfe the water poured 

 down will run over his mill-dam and be wafted ; but, in the 

 former inftance, the water would have come down lefs fud- 

 denly, and he might be able to fet to work before the whole 

 of the water had efcaped over his weir. 



In inch a cafe the lower miller may be inchned to 

 appeal to the law, but he will find that he has no right to 

 prevent his neighbour above from ufing the water in the 

 fame manner as he does himfelf, and if he finds any altera- 

 tion in his own mill, it is for want of a capacious mill-pond 

 to referve the water. In the original ftate the channel of 

 tlie river in his neighbour's ground above ferved him in fome 

 meafure as a mill-dam, by retaiiinigllie water for a given time, 

 ihoiigli it would not retain it permanently. The advantage 

 of this he had enjoyed for j long lime, wlicn it was no in- 

 conveuicnce to his neighbour, but had acquired no right to 



demand 



