The ferocity of the weather should not be underestimated. In 1868 a huge wave washed over the top of Geirum Mor, taking the sheep with it. The summit of the islet is 51 metres (170 ft) above sea level. Fraser Darling and Boyd (1969) also speculate about the "quiet failure" of the populations of small islands like Mingulay to husband their available natural resources. Certainly the population began to exceed the carrying capacity of the land. The Congested Districts Board installed a derrick to assist with the landings at Aneir at the south end of the Bay in 1901, but the design was flawed and its failure was a further disappointment.