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described, but if the sluice must be laid in a water-course, and 

 that you can avail yourself of a sluice at front or behind, 

 you can let in water and float the cylinder to its destination. 

 To make it sink slowly and regularly upon its bedding, you 

 must then first bore a few holes in the stops of the two open- 

 ings, when it will fill wholly or partially with water and sink. 



When the cylinder is once in place, the first requisite is to 

 take care that it lies perfectly level, as otherwise the closing 

 of the door will always be attended with some difficulty. 



Though this work is mostly done in the dry season, it may 

 happen, that by a sudden shower a quantity of water may 

 flow under the sluice-cylinders already laid, and make them 

 rise or shift. As a precaution it is advisable to prevent the 

 cylinder's moving, when it is once fixed in its place and 

 levelled, by driving on both sides of it strong piles into the 

 ground, and above this upon the body of the cylinders lay 

 cross beams, in such a manner as to secure it firmly and render 

 it immoveable. 



On throwing in the ground, care should be taken to spread 

 the earth equally everywhere, that no unequal lumps may 

 interfere and shove the cylinder aside. 



The greatest care should be observed as to the water- 

 tightness, and likewise in the placing of the cylinder, whether 

 it be let down or floated. The smallest inattention, a tri- 

 fling neglect, may cause the sluice to plunge over, and it will 

 cost hands full of money to restore it to its proper position. 



As soon as all this is done properly, the back slide-valve 

 and the front door, being a tankard-lid door, should be fitted in, 



