In attempting an explanation of the structure of Western Cornwall it seems fairly evident that the first step should be a study of the coast sections, for the interior of the country is so folded and buckled that it is quite bewildering in its complexity. The natural sections most useful for this purpose are those of Black Head to Gorran Haven, St. Michael Carhayes to the Dodman, Falmouth to the Manacles, and Trewavas to Mullion, since all these sections cross the lines of strike more or less at right angles. It soon becomes abundantly clear that the complexity of folding exhibited by the rocks is but the detail of greater movements and need not seriously detain us. In 1908 Upfield Green expressed our views on those greater movements in the ninety-fifth report of the Trans. Roy. Geol. Soc. Cornwall, and endeavoured to show that the great Hercynian movements had involved Cornwall, throwing the country into three east and west anticlinals with sinuous outcrops, which anticlinals had gradually been forced over to the north into overfolds. These folds have been further complicated, distorted, and confused by local minor bucklings shown by the strata on every side.