1 Bz4' That Is, By The Coefficient Of Z W In **Zp** '.

1 **Zp** 2.

1 **Zp** 0.1 Z 4 1.1 Z 2.

The components of velocity of the moving origin are denoted by U, V, W, and the components of angular velocity of the frame of reference by P, Q, R; and then if u, v, w denote the components of fluid velocity in space, and u', v', w' the components relative to the axes at a point (x, y, z) fixed to the frame of reference, we have u =U +u' - yR +zQ, v =V +v -**zP** +xR, w=W +w -xQ +yP.

.) = (X-jfidp) +m (Y-dy) +n (**Zp** 2), for all values of 1, m, n, leading to the equations of motion with moving axes.

Z, v' -V --**zP** - x R b2 2b2 c2 S2 1 z a2+ 2b2S23x, w' = w -{-xQ-yP2c2 cl?

Let E be the effective elasticity of the aether; then E = pc t, where p is its density, and c the velocity of light which is 3 X 10 10 cm./sec. If = A cos" (t - x/c) is the linear vibration, the stress is E dE/dx; and the total energy, which is twice the kinetic energy **Zp**(d/dt) 2 dx, is 2pn2A2 per cm., which is thus equal to 1.8 ergs as above.

Now X = 27rc/n, so that if A/X=k, we have **Zp**(27rck) 2 = iï¿½8, giving p----1022 k2 and E io l k2.