J. W. Gregory - Collectors in East Africa - 8.

By Bernard Verdcourt

John Walter Gregory was born in London on 27th. January 1864, the only son of a wool merchant. He joined the British Museum (Nat. Hist.) in 1887 and remained an assistant in the Geology Dept. until 1900. From then until 1904 he was professor of geology at Melbourne University, and from 1904 until 1929 at Glasgow University. He then retired to Essex having travelled to most parts of the world including Tibet, Peru, China, Russia, Australia, Africa, Canada, New Zealand, etc..

Gregory arrived in East Africa as a member of an abortive expedition in 1892. Since he very understandably did not want to return with nothing to show for the time spent, he organised a trip to the Great Rift Valley and north to Lake Baringo. The only white man in the party, he managed to ascend Mt. Kenya to 15,000 ft. and stood on the Lewis Glacier, possibly the first time anybody had done so, certainly the first white man to do so.

Being a geomorphologist he could really make the most of this opportunity. He later gave a brief description in his book of the physiography of the south-western slopes and discussed glacial geology at considerable length. He discovered old moraine material in the forest at an altitude of only 9,800 ft. and, above the forest zone, recognised the wide range of glaciation phenomena extending from 11,000 ft. up to the peaks.

Of particular interest is Gregory’s contention that the mountain was covered by a shield or dome of ice rather than by a system of long valley glaciers. A sketch map of Gregory’s made in 1893 shows the Lewis Glacier extending several hundred feet further down than it does today, and his map also shows only one of the two icefalls which are visible at the present time. The upper one is shown covered by the glaciers and marked by a line of crevasses. He linked the maximum of glaciation with the maximum extention of the East African Lakes – the embryo of a local pluvial-glacial correlation hypothesis.

He picked up a number of molluscs which Smith wrote about in 1894; and also collected some in spirit since Godwin Austen reported on some Trochonanina in 1895. Several of the slugs he collected are still unworked – I did not know of the existence of the material until after my own studies on the group. He also made a study of the volcanic geology of the mountain and of the Great Rift Valley and he wrote several papers and books on the subject. One is amazed how much he managed to do during a relatively short expedition. His book "The Great Rift Valley" 1896 is very interesting reading, particularly to anyone who has lived close to the areas he has written about. His extensive work gained him election to the Royal Society in 1901. He met his death in the rapids of the Urubamba River at Pongo de Mainique in Peru in June 1932.

List of molluscs described from material collected by J. W. Gregory

References

Smith, E.A. (1894).

B. Verdcourt