Abstract

1831 was a momentous year for Charles Darwin. He passed his BA examination on 22 January, stayed up in Cambridge for two further terms and returned to The Mount, his home in Shrewsbury, in mid-June. On 6 August he left Shrewsbury with Adam Sedgwick for a geological field trip to North Wales, and after his lone traverse over the Harlech Dome returned to The Mount on Monday 29 August to find letters from John Stevens Henslow and George Peacock inviting him to joint HMS Beagle. This geological field trip was crucial for his work on the Beagle. For example, when he began his first geological work of the voyage on Quail Island, he was by that time a competent geologist. Though others have studied the North Wales tour in some detail, there is also another earlier and much briefer episode to consider. Darwin appears to have geologized on his own at Llanymynech in July. The contrast between his first recorded attempts at Llanymynech in July 1831 and then elsewhere in North Wales in August 1831 is most instructive, as his development as a geologist can be followed in his field notes. Retracing his steps today, and comparing his measurements and observations with new ones, throws light on what he might have learnt at different points during that summer