Industrial chemist. Born in and educated in Edinburgh, Beilby began working in the Scottish oil-shale industry in 1869. He was able to increase the yield of paraffin extracted from the shale by improving the distillation process. He went on to develop and patent a process for the bulk synthesis of potassium cyanide, for use in the gold-extraction industry, by passing ammonia over a heated mixture of charcoal and potassium carbonate.
Beilby advised the Admiralty how oil could be produced by the low temperature carbonisation of coal. He also discovered the Beilby Layer, a film which forms on the surface of a metal by plastic flow when a metal is polished.
An enthusiast for technical education, Beilby served as a Governor of the Royal Technical College in Glasgow from 1907.
He was knighted in 1916 and died in London.