Similarly, the inertia parallel to Oy and Oz is **NW**' - 1 B W', B C (b2 +-X, c 2 ab and A +C abc/ZP, Ao For a sphere a=b=c, Ao= Bo=Co =, 'a' = Q = = z, (9) U from (II), (16) so that the effective inertia of a sphere is increased by half the weight of liquid displaced; and in frictionless air or liquid the sphere, of weight W, will describe a parabola with vertical acceleration W - W', g (30) W+ aW Thus a spherical air bubble, in which W/W' is insensible, will begin to rise in water with acceleration 2g.

Thus the path of the ray when the aether is at rest is the curve which makes fds/V least; but when it is in motion it is the curve which makes fds/(V+lug-m y -I-**nw**) least, where (l,m,n) is the direction vector of Ss.

Let n, w be two quasi-scalars such that r t e =n, con = w, **nw** =w 2 = o.

It did not cease to exist, but the Greek life and political unity were destroyed, and the Smyrnaean state was organized on the village system (WKeiro **nw** j .o tiv).