The integration can be effected without much difficulty.
Here again, on integration over the entire lamina, the aggregate effect of the secondary waves is necessarily the same as that of the primary.
He published a memoir on the integration of partial differential equations and a few others, which have not been noticed above, but they relate to subjects with which his name is not especially associated.
For a point Q outside the shadow the integration extends over more than half the primary wave.
By the principle of superposition the whole effect may be found by integration of the partial effects due to each element of the surface, the other elements remaining at rest.