Edward Greenly was a geologist perhaps known best for his detailed geological survey of the island of Anglesey, North Wales, which took him and his wife, Anne Greenly, 24 years to complete. This short book is a summary of the prevailing geological understanding of the Earth at the time of writing (1927), aimed at the public. It is an absolute delight to read, as it comes from a time when it was okay to combine poetry and science. As a geologist I also found it quite an eye-opener, for almost every highlighted unknown in the book has since, for the most part at least, been resolved by the theory of plate tectonics or through further research into the uses of radioactivity. For instance, he was writing at a time when the age of the Earth and its rocks could only be guessed at, without the help of radioisotope dating. In other parts he could almost be describing plate tectonics, without actually knowing about them. Only by reading these old geological texts can you really understand how geology came to be the science it is today. We have come so far in less than 100 years! Greenly also quotes parts of the poem "In Memoriam A.A.H." by Tennyson throughout the book. The quotes themselves are beautiful little illustrations of how the boundaries between art and science were far blurrier than they are today, and I love the romance of it all. It only struck me later that this poem, which explores grief at the loss of a loved one, could have been close to his heart at this point in life, as his wife (and field assistant, editor, illustrator...) Anne Greenly passed away shortly before its publication.