The formation of lakes was effected by damming up some small brooks and rivulets, in the valleys which emptied themselves into Virginia Water. The dams were raised on piles formed from the ends of fir poles, which, to make a firm foundation, were driven into the ground about ten or fifteen feet wider at the base than the road was at the top. The sides were built with good sods, and filled in with the best soil that could be gathered on the spot. Where the bog was unstable, it was replaced by stiff clay, which was puddled. In this way two or three fine expansive sheets of water were formed, which were extremely useful for the cavalry horses; and a safe and ready passage was also afforded for the troops across some valleys and morasses over the roadway of the dam. One sheet was behind the cavalry stabling on Egham Common, and the others, named “The Great Arm” and “The Little Arm,” were at the base of Black-hill and of Sheep’s-hill. The stables were constructed of a uniform width, but the length varied according to circumstances. For a stable of six horses, the dimensions were twenty-seven feet by thirteen feet six inches. The uprights or stanchions were nine feet long, three feet of which were driven into the ground and well rammed. A wall-plate was then fixed to the stanchions at the height of six feet from the ground. The rafters were made of rough poles, secured by a collar-beam four feet from the top, and then nailed firmly down on the wall-plates, every alternate one being strapped with hoop-iron. The centre was supported by a king-post rammed three feet into the ground, and besides being nailed to the collar-beam, was tied for steadiness and stability at the top with rope-yarn. Poles were also fixed and secured on either side and at the ends, which, with the doors, were thatched or wickered with fir branches, compactly intertwined. The whole was roofed with canvas, and stayed by guy-ropes. The canvas was made under contract, in pieces to cover a stable for six horses, but after a few days’ rain the pieces shrunk about sixteen inches, and caused throughout the period of the camp much inconvenience to the horses. The stabling was made to accommodate 1,800 horses at an expense of nearly 1,000_l._ An experimental stable of the above form was run up in two hours and a quarter by twelve men, under sergeant George Pringle, directed by Lieutenant Drake, in the presence of the Commander-in-Chief—Viscount Hardinge—who expressed his satisfaction both with the exertions of the men and the suitability of the construction.