Less than two centuries ago - barely a blink of an eye in Earth time - devout Englishmen pronounced that the fossils of animals that lived tens of thousands (or even millions) of years ago, had once been creatures killed in the Biblical flood survived only by Noah and his 'passengers'. In the standard early Victorian view, the Earth was created in 4004bc, and the alluvial deposits around the mouth of the Thames sat on top of debris left by the flood. Generations of geologists later, the Earth is now generally accepted to be about 4.5 billion years old.

The prospective reader of Earth Time should take its subtitle seriously: "Exploring the Deep Past from Victorian England to the Grand Canyon". The first half of the book is largely a history of the geologists of Victorian England who worked to understand the rock strata of their own British Isles. Geologists of other periods and areas are mentioned primarily to illuminate Victorian views of the geology of Britain from the Cambrian era to the present.

Part II is anchored on the geological exploration of the Grand Canyon by John Powell. Because of the extreme age and the complex history of the earliest rocks in the canyon, the author also looks at the efforts of geologists up to the present time to understand the Pre-Cambrian era worldwide. He also examines important whole-Earth matters such as the 'snowball Earth' theory; the shape of the hypothetical continent of Rodinia about a billion years ago; the first signs of life on Earth; and extinction events in the fossil record.

The concepts Palmer works to explain are fascinating, if frequently complex, but his prose lacks lucidity and some passages are confusing.

Worse, there are significant typos - including a missed decimal point on page 4, which results in readers being told the beginning of the Pleistocene at 1,608 million years ago (rather than 1.608). Nonetheless, the subject matter is always fascinating, and it's well worth persevering with the read.

Earth Time includes many delightful reproductions of illustrations taken from the works of the geologists whose lives are celebrated.

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