A Search for an Einstein Relativity-Gravitational Effect in the Sun.

This has clearly nothing to do with b = 0, the condition that Xo be a stationary line of the quartic. Therefore the cusps of the Steinerian do not lie on the stationary lines, as might be expected from their number -twenty-four. n = 0 is the condition that x2 = 0 be the tangent to the Hessian; then the cusp cannot be obtained by making cl = 0, for then the Hessian has a double point. Putting I = 0 shows that the cusp tangent is also the tangent to the Hessian. Use of n = 0 also shows that the polar points of lines of the Cayleyan as to (tt)6 lie on the corresponding tangents to the Hessian.