In 1890 Monash resolved to complete his degrees. On 4 April 1891 he took out his B.C.E., having won the Argus scholarship with a high second-class honour. In 1891-92 he crammed himself through the exams for municipal surveyors’ and water-supply engineers’ qualifications.
Identifying a possible lucrative monopoly in legal engineering, again in 1891-92 he forced himself through a law degree, by last-minute cramming, probably without having attended a single lecture. In December 1892 he completed arts by conquering his bugbear Latin. He formally graduated (M.Eng., 1893; B.A., LL.B., 1895) when he could afford the fees. It had been an astonishing spare-time programme. Given opportunity and concentration, he might have won first-class honours in any of engineering, mathematics, modern languages, philosophy or English literature.
Later he became the President of the Victoria Institute of Engineers according to his Wikepedia page which outlines more of his career history in concrete and construction.