The Geological History of Gower by T. R. OWEN. HAVE YOU WATCHED A MAN building his own house? To begin with, he usually takes a long time to do it and there are often long periods of inactivity. Moreover, his work is divided into a number of phases. He begins by laying a sound foundation, something that will stand the wear and tear of time. Then he begins to build, the walls rise slowly, and the house begins to take a rough (but not the final) form. At this stage, the man often seems to stop work for a long period and the untiled roof of the "skeleton" house is covered over with great, thick tarpaulins which almost hide the house from view. Eventually the cover is removed and the house is finally completed. The reader will no doubt wonder what all this has to do with the geological history of Gower, but in fact the building of Gower can be very closely likened to the building of that house. It took an awful long time to "build" Gower (at least 400 million years) and that building was accomplished in a number of distinct, inter- rupted, phases. One long "break" occured between 250 and 100 million years ago, when an already roughly-planned Gower surface was buried (and therefore preserved) beneath a "tarpaulin" of Mesozoic sediments. This cover has since been removed (with the exception of a small patch of Triassic at Port Eynon) and natural agents of erosion have given a final trimming to produce the modern Gower surface and outline which we love so much. Geological time is subdivided into a number of major divisions as follows (the youngest first): Quaternary -Began 1 million years ago. Tertiary -Began 80 million years ago. Cretaceous -Began 140 million years ago. Jurassic -Began 170 million years ago. Triassic -Began 210 million years ago. Permian -Began 260 million years ago. Carboniferous -Began 330 million years ago. Devonian -Began 370 million years ago. Silurian -Began 410 million years ago. Ordovician -Began 480 million years ago. Cambrian -Began 600 million years ago. Pre-Cambrian -Began 4000? million years ago. The pre-Devonian story of Gower is shrouded in mist and we must begin our tale at the commencement of Devonian times, when