page 175 note * Our correspondent here uses the word swallow-holes with a meaning somewhat different from that in which it is usually applied. Swallow-holes are the conical cavities on the surface of some parts of the country into which water runs either permanently or during heavy rains (see Prestwich “On some Swallow holes near Canterbury,” Quart.Jour.Geol. Soc., vol. x. p. 222), and though these swallow-holes are regarded as actual representatives of the original condition of many of the conical hollows, the sections of which are often seen in tbe exposed chalk-strata, yet the latter are called sand-pipes, sand-galls, &c.