1865 - began his engineering career as a pupil of his father, Henry Holt, Civil Engineer, of Leeds and Wakefield. 1868 - was an Improver at the Yorkshire Engine Co’s Works, Sheffield, under A. L. Sacre in charge of the erection and repairs of locomotive engines. 1871 - took his father’s place and share in the firm of Holt and Childe, Civil and Mining Engineers, of Wakefield. 1872 - also practised in London, carrying out various works. 1875 - elected an Associate of the Institution of Engineers. 1881 - joined the firm of Messrs. Crossley Bros., Ltd, and designed and superintended the erection of a portion of the Otto Gas-Engine Works at Openshaw.