Forever shifting

In his poem of grief and loss In Memoriam, the Victorian poet Alfred Lord Tennyson adapts an ancient image of change to describe the seemingly solid earth beneath his feet:

The hills are shadows, and they flow
From form to form, and nothing stands;
They melt like mist, the solid lands,

Like clouds they shape themselves and go.

The analogy may have been thousands of years old, but Tennyson was being radically literal in its usage. While he was working on the poem, in the 1840s, a series of scientific works had recently appeared that challenged everything people took for granted about the Earth and humanity’s place in its, in 1830-33, and Robert Chambers’s , in 1844. More than a decade before Darwin published his , the young science of geology brought astonishing and discomforting descriptions of a planet whose age might be measured in millions, even billions, of years, rather than the thousands previously assumed.