A Doctor who practised for most of his professional life at Southport where he was one of the founders of the Southport Natural Science Society and editor of their Proceedings. His natural history interests included the Foraminifera, on which he published many papers of the local fauna, the mollusca and the Coleoptera. He died at the early age of 47 from pleuro-pneumonia.

His first article in the EMM.: 'Stray notes on a few Southport Coleoptera' was published in 1900 (11, 287.) and his last in the same periodical in January 1905. The Southport 'notes' derived from his 'Coleoptera of Southport and District' published in the Proceedings of the Southport Natural History Society, 1899 which in turn was apparently expanded in the Handbook of the British Association's visit to Southport in 1903 when Chaster contributed with Burgess Sopp what W.E.Sharp described as 'a most interesting and instructive section on the Coleoptera of the Southport district. This has been separately reprinted, and as a scientific contribution to faunistic distribution, as well as a guide to the Coleoptera of that particular district leaves nothing to be desired' (Sharp,1908, 14-15).

He also collected in Nottinghamshire (see J. W. Carr, The Invertebrate fauna of Nottinghamshire, 1916) and in Ireland (see Johnson & Halbert (1902), 542. In this last he added two species from Roundstone to the Irish list (IN., 12, 1902, 167) and published a list of specimens collected at Ballycastle, Co. Antrim with B. Tomlin (IN., 11, 1902, 61-65).

Chaster’s collection, amounting to 11,000 insects, is in the NMW. There is a brief obituary in EMM., 46, 1910, 145-146. (MD 3/02)