APPENDIX B 435 



simply means a rough preparation of the river-bed on all sictes of the proposed 

 erection and extending slightly beyond its base. On the centre of the founda- 

 tion a dry-stone wall from ] to 2 feet wide should be built in fairly regular 

 layers, one or two of which should consist of binding-stones. The wall should 

 be let well into the bank at its starting point, and terminate a few feet short of 

 the extremity of the foundations, leaving space for the addition of the protective 

 apron at the proper slope. Larger stones with a flattish surface will do for 

 " coping," and afford good foothold to the angler. The elevation at each end 

 will depend on the effect the croy is intended to exercise ; but as a rule the top 

 of the wall should be highest where it leaves the bank and incline downwards 

 towards the water, and generally the slope of the river-bed contributes to this 

 result. It must be protected on all sides by an apron of stones to give it 

 solidity, and to guide the water over it, or along it, with the least amount of 

 resistance, The slope of the apron must be not less than 1 in 2, and may often 

 with advantage be 1 in 5, especially in low croys that have to withstand a heavy 

 rush of water. The stones forming the surface of the slope need not be of large 

 size, but must be " causewayed " or " cobbled " and well wedged together, begin- 

 ning at the foundations and working upwards to the top of the copestones, and 

 smaller material can be thrown over them to fill up the interstices. Particular 

 care must be taken to round off the end of the croy, that the water may not find 

 too much to lay hold of. 



The cost of stone croys depends principally on the distance the stone has to 

 be carried, but if there is a good supply along the river bank within 50 or 100 

 yards, the expense should be small ; perhaps about Is. a running foot for a croy 

 about 2 feet high, so that if it extended for 30 feet the cost will be only 30s. 



Where stones are scarce, a very effective croy can be constructed of several 

 layers of old railway sleepers laid on edge, and end to end. A sleeper measures 

 about 9 feet by 10 inches, and costs, say, Is., so that a croy 27 feet long and 2 

 feet high requires three rows, each composed of three sleepers, or nine in all, 

 and in calculating how far it will extend into the river, allowance must be made 

 for the ends being inserted in the bank. The sleepers should be joined together 

 by iron plates and bolted on to stout supports of angle-iron sharpened at one 

 end, and previously driven into the bed of the river at convenient distances, but 

 not too widely apart, as each sleeper should be well secured. Holes should be 

 made in the face of the angle-iron, against which the sleepers will rest, to pass 

 bolts through, and corresponding holes can easily be bored with an augur in the 

 sleepers when placed in position. If there are some stones near, they can be 

 used to strengthen the woodwork by throwing them in on each side, but the 

 erection of a wooden croy generally implies a scarcity of stone. The ironwork 

 adds considerably to the cost of the structure, and makes it more expensive than 

 a stone croy by 50 to 70 per cent. On the other hand, when well built, it 

 should stand for a long time without any repair. 



There are other materials that can be used instead of stone and wood, and a 

 mound of gravel or earth covered with turf will resist a good flow of water, 

 provided that the turf has time to catch a firm hold before it is submerged. 



Wattling with alder branches, or any other convenient wood, forms a useful 

 protection to the banks above and below a croy, where the action of the water 



2E2 



