THE "beach" on our English coast is an accumulation of pebbles or of sand, or of both, often accompanied by dead shells and other fragments thrown up by the sea. Very generally it slopes rapidly from above high-water mark to about half-tide limit, and then merges into a more horizontal expanse of fine, compact sand. This last is not "a beach" thrown up by waves, but a sediment or deposit. It forms a flat, often ripple-marked plain (much has been written as to how those ripple-marks are produced), which is exposed at low water, the sea retreating for a quarter or even half a mile or more over it, on some level shores. Sometimes, though rarely, the sea rises and falls against a hard, rocky cliff without forming any beach or exposing any "shore" even at low tide. This occurs on parts of the Cornish coast, where the Atlantic beats against adamantine cliffs, which even at low tide rise sheer from the water. Again, it sometimes happens that the shore is simply formed of a terrace of sloping hard rock, without any "beach." But on the coast of England generally there is a good beach of sand or pebbles, or both, overlying the native rock or clay, and sometimes it is growing every year, so as to extend the land surface seawards and add new acres to the possessions of the landlord. On other parts of the coast the beach "travels," being driven along the underlying solid shore by the prevailing direction of the tidal currents and by the waves. The sea-waves break close to the soft cliffs of clay, sand, and sandstone. These are continually crumbling away owing to the action of land water, which soaks from the surface down to the layers of clay and forms subterranean springs and streams. They undermine the face of the cliff and cause the upper parts to topple. When there is a big, broad, growing beach in front of such a cliff, the breaking down or "toppling" of its face only leads to the formation of a slope (at the "angle of rest"), and things remain but little changed for ages. But if the beach is not being piled up and added to and growing out seawards year by year, and is, on the contrary, a travelling beach, then the sea comes close up to the cliff, and when masses of it topple on to the beach the sea washes them away, and no "slope of repose" is formed. The cliff keeps on toppling as it is undermined by springs of land water. Its natural buttress against further breakage--namely, its own fallen material--instead of resting against it as a great sloping, protective bank, is washed away by the sea as fast as it falls, and is carried down the coast by the tidal currents. This is the story of "coast erosion" about which there has recently been a Government inquiry. Where the combined action of prevailing winds and sea currents is throwing up and adding to the beach there is no coast erosion. The causes of the sea currents on our coasts are not easy to determine, as they are connected with the