638 
EXPERIMENTS OP MESSRS. FINCHAM AND RAWSON. 
the class of which fig. 4 is the type, the centre of gravity of whose displacement 
descends in the act of rolling, she will roll the faster as this centre of gravity is seated 
deeper in her hull, 
45. It may be received as a general rule that (other things being the same) vessels 
of the class fig. 4 roll more quickly than those of the class fig. 3, but do not roll so far. 
So that unless some special provision be made for that end, stability in rolling may 
not, and will not probably be obtained except at the expense of quick rolling. 
46. The form under which A enters equation 24, shows that breadth of beam is 
not of itself conducive to slow rolling, and that it can only tend to it indirectly, by 
carrying the ship’s weights further from the axis about which it rolls, and thereby 
augmenting the quantity k, which represents in the formula the moment of inertia of 
the ship, and is the ruling element of the time. The form under which Wi enters the 
equation shows heavy loading to be conducive to slow rolling. 
47 . It would be unsafe however to be guided in the construction of a ship by any 
one of these considerations taken separately from the rest, for there is scarcely any 
element of the discussion which can be changed without bringing about a change 
in an opposite direction in some other. 
What will be the total result of any proposed change, and by what means the whole 
object sought by it is to be accomplished, can only be determined by that complete 
mathematical discussion of the question in all its elements, the principles of which it 
has been the object of this paper to develope, and which the formulae contained in it 
afford a means of applying. 
December 1, 1849. 
APPENDIX. 
Experiments on the Dynamical Stability and the Oscillations of Floating Bodies. By 
John Fincham, Esq., Master Shipwright in Her Majesty's Dockyard, Portsmouth, 
and Robert Rawson, Esq. 
Experiments necessary to verify the formula 6, 
U(^)=W(AHi-AH,), 
which represents the work done in deflecting a floating body through an angle 
such that the height through which the centre of gravity of the floating body is 
raised shall be AHj ; and the height through which the centre of gravity of dis- 
placement is raised, shall be Allg. 
For this purpose two models were made, such that their sections were uniform 
throughout the whole length of the model : the section of one was a triangle, and of 
the other a circle (see figs. 1, 2). 
If the reader will refer to Art. 10 for a general description of the apparatus, the 
following explanation of the drawing fig. 1 will be sufficient to show how the experi- 
