P { −(A + Ma2) n2 + Kn + gMa} − RMn2a = 0;

(17)

and so the effect may be investigated on the Fleuriais gyroscopic horizon of the motion of the ship.

Suppose the motion λ is due to the suspension of the gyrostat from a point on the axis of a second gyrostat suspended from a fixed point.

Distinguishing the second gyrostat by a suffix, then λ = bῶ1, if b denotes the distance between the points of suspension of the two gyrostats; and the motion of the second gyrostat influenced by the reaction of the first, is given by

(A1 + M1h12)ῶ1 − K1ῶ1i

= −g (M1h1 + Mb) ῶ1 − b (X + Yi) = −g (M1h1 + Mb) ῶ1 − Mb(aῶ + λ);

(18)

so that, in the small vibration,

R{ −(A1 + M1h12) n2 + K1n + g (M1h1 + Mb) } = Mn2b (aP + R),
b