Sck ell's Lan dscape- Garden ing. 265 



work. It is a good plan to dig through the middle of the lake 

 first, that is, to form an empty space of about 30 ft; wide, so that 

 the carts may have plenty of room ; and to distinctly mark 

 out the concave line the bed is to assume. This sort of excava- 

 tion has much resemblance to the excavation of valleys ; only, 

 in this case, it is not necessary to give any other than the usual 

 concave form to the bed, which is under water, with the proper 

 depth, declining towards the outlet. 



When unsightly bogs or hollows have been filled up with the 

 earth, and lawns or plantations improved, the remainder may be 

 made use of in raising hills in suitable situations. 



3. Besides the usual sluices composed of boards, which are 

 raised and lowered by means of rollers, there is a much more 

 simple construction, composed of movable rectangular pieces of 

 wood, laid one upon another in grooves in pillars, by means of 

 which the water is retained or let off". This very old invention, 

 on account of its particular simplicity and usefulness, and because 

 it is not visible in pleasure-grounds, and consequently cannot 

 prove a disagreeable object, I will explain to the modern artist, 

 who may chance not to be acquainted with it. 



In the spot where a sluice is to be constructed, a paved bed 

 must be made for the water, so that it may neither undermine 

 the sides nor the posts of the sluice, nor become very deep, nor 

 cause any other damage. At the same time, the two posts of the 

 sluice, either made of stone or of oak, must be set up from ten 

 to twenty feet apart, according to the required space or opening. 

 On the inner sides of these posts grooves must be cut, which 

 may be about 6 in. wide and 5 in. deep ; and in these the sluice- 

 boards (stauholzer) are to be laid. 



These two pillars or posts must be united by a horizontal 

 beam, on which the first sluice-board may be firmly laid. 

 When the grooves in the pillars are six inches wide, the boards 

 may be 5 in. thick, to allow room for them to play, and from 6 in. 

 to 7 in. deep. They may also be made as thick as they are deep ; 

 this only depends on their length, because at the same time care 

 must be taken that they are not too heavy, that they may be 

 easily laid in, and easily taken out again. 



If, for example, the space between the pillars is 10 ft. (the 

 depth of the groove included), the boards should only be 9 ft. I Oin. 

 long, to allow them sufficient room to play in the groove, and 

 that they may not be in danger of sticking when being taken out 

 or put in. Each of these boards, the number of which is deter- 

 mined by the height of the water, must be provided at each end 

 with a round plug (either of wood or of iron), projecting hori- 

 zontally 6 in. on each side, so that it may be taken hold of with 

 the hand or any instrument; and by means of these plugs the 

 board may be taken out and put in again. By means of these 

 boards, which are laid quite simply close over each other in 



