60 (hi reclaiming Marsh Land. 



to it, and a like piece upon the top of the sluice over the 

 side plank, and through these four pieces of scantlinp: to 

 bore a two- inch hole, through which is passed a good 

 wooden pin or iron bolt to hold the door securely, and 

 permit it to open and shut easily. The advantage of 

 hanging the door a little within the sluice, is, to prevent 

 its being injured by ice, or by pieces of floating timber, 

 and by admitting the discharge of the water more freely 

 from it, for in leaving the sluice it glides away in a smooth 

 current, whereas, if the door was hung at. the mouth, the 

 water would pitch down, and wear a deep hole immedi- 

 ately on its leaving the mouth. If it should be thought 

 necessary to have a large sluice, say six, eight, or ten 

 feet wide, the division plank must be increased to the 

 number of intended funnels : thus, if there are to be three 

 funnels, then there must be two division planks, and so on^ 



FLOOD-GATE. 



The flood-gate is constructed of sills, ties^ caps, posts, 

 and studs, all mortised and tenanted into each other, in 

 the same manner as any ordinary frame building, by hav- 

 ing its bottom planked tight, and its sides boarded up 

 with its door or doors hung to the posts, in the same 

 manner as a common stable door. Now it must be ob- 

 vious to any person, that so much wood work exposed 

 to the alternate operation of wet and dry, must, in a few 

 years, give way, while the sluice which has been well 

 laid, and is never dry, will, of course, resist the effects of 

 decay for very many years. 



GREEKS AND DAMS, 



It sometimes happens in large tracts of marsh about to 

 be reclaimed, that there are creeks of considerable width 

 and depth, with a strong tide setting through them, and 



