to high speeds, and will permit of realizing, in the future, important
saving in the power expended, and, consequently, in the fuel (much less
of which will need to be carried), in order to perform a given passage
within a given length of time. Thus is explained the great interest that
attaches to Mr. Pictet's labors, and the desire that we have to soon be
able to make known the results obtained with such great speeds, not when
the boat is towed, but when its propulsion is effected through its
own helix actuated by its own engine, which, up to the present,
unfortunately, has through its defects been powerless to furnish the
necessary amount of power for the purpose.--_La Nature_.

* * * * *




INITIAL STABILITY INDICATOR FOR SHIPS.


For a vessel with a given displacement, the metacenter and center of
gravity being known, it is easy to lay off in the form of a diagram
its stability or power of righting for any given angle of heel. Such a
diagram is shown in Fig. 3, in which the abscissae are the angles of the
heel, and the ordinates the various lengths of the levers, at the end
of which the whole weight of the vessel is acting to right itself.
The curve may be constructed in the following manner: Having found by
calculation the position of the transverse metacenter, M, for a given
displacement--Figs. 1 and 2--the metacentric height, G M, is then
determined either by calculations, or more correctly by experiment, by
varying the position of weights of known magnitude, or by the stability