82 Col Beaufoy on the [Feb. 



nected the sides of the model, and through which the mast was 

 inserted. A second alteration consisted in a more accurate 

 adjustment of the centre of gravity at any given point of the 

 figure when loaded. Raising the ballast (bars of lead) at first 

 nearly produced this effect, which was afterwards determined 

 with greater nicety by pouring shot into a cup fixed upon the 

 top of the mast. This contrivance so well answered the intended 

 purpose, that the results of several trials were found not to vary 

 from each other more than five-hundreths of an inch. 



Different formed bodies were used, measuring in breadth ten 

 inches, and in length fourteen inches, or within a few hundredths 

 of an inch of fourteen. The immersion in water, with the 

 exception of the three last, was four inches, or two-fifths of the 

 width. The total depths were various, those bodies whose sides 

 projected outwards requiring greater depth than those with sides 

 inclining inwards; and for this reason, the edge of the former 

 when inclined becomes sooner level with the surface of the 

 water. 



Fig. 1 has the sides parallel to the plane of the mast both 

 above and beneath the water line. 



Fig. 2 has the sides projecting 15 degrees oitticard above the 

 water line, and parallel to the masts under. 



Fig. 3 has the sides inclining inwards 15 degrees above the 

 water line, and parallel to the plane of the masts under. 



Fig. 4 has the sides projecting outwards, and at equal incli- 

 nations (15 degrees both above and beneath the water line). 



Fig. 5 has the sides inclining inwards and at equal inclina- 

 tions (15 degrees) to the plane of the masts above and below the 

 water line. 



Fig. 6 has the sides coincident with the surface of a cylinder, 

 the vertical sections being equal circles. 



Fig. 7 has the vertical sections terminated by the arcs of a 

 parabola. 



Figs. 8, 9, 10, refer to the experiments made on the greatest 

 vertical section (or midship bend) of an 18 gun brig, the Leopard 

 of 50 guns, and the Howe of 120 guns. 



In fig. 1 (Plate XXVI), B A is the surface of the water when 

 the vessels float upright. C H the water line when they incline 

 30 degrees. E refers equally to the centres of gravity of the 

 displaced fluid when the figure floats horizontally, and to the 

 models in the first set of experiments. G is the centre of gravity 

 of the model in the second set of experiments ; the distance EG 

 being 1 "3 inches, or -±g^ of the breadth BA; E R, and G r, are 

 the lever on which the water acts to re-establish the vessel in a 

 vertical position. M is the meta centre, or point below which 

 the vessel's centre of gravity ought always to be situated to 

 prevent its oversetting. 



The displaced water, as well as the weights applied to incline 



