by T. D. Spearman
Humphrey Lloyd, the son of Bartholomew Lloyd, was born in Dublin in 1800. He entered College in 1815, was elected a Scholar in 1818 and Fellow in 1824. He was appointed to the Chair of Natural and Experimental Philosophy vacated by his father on becoming Provost in 1831. He in turn was to become Provost in 1867, Lloyd made major contributions and achieved international distinction in two areas of physics: physical optics and terrestrial magnetism.
Physical optics was at that time a subject of intense interest and controversy with the debate still raging between the corpuscular and wave theories of light. Lloyd's observation of the phenomenon of conical refraction, following Hamilton's prediction of it, was a major scientific event. His experimental results, including this observation, systematically supported the wave theory and he was an effective advocate of that viewpoint.
Lloyd was one of the leaders in an international co-operative scientific programme, unprecedented in its scale and sophistication, to study systematically the variation of the Earth's magnetic field. This involved the construction of a network of specially designed observatories, with standardized measuring instruments, spanning the globe - from Peking to Toronto from Van Diemen's Land to Siberia. Equipment was also fitted in East India - men, and naval frigates carried instruments to the Zambesi river, the North West Passage and the Antarctic. In 1840, in his own observatory in the College, Lloyd and his three assistants were taking observations every alternate hour, day and night, despite some scruples about Sabbath observance!
One of Humphrey Lloyd's important initiatives within the College, in which he was joined by James Mac Cullagh and Thomas Luby who was another of the mathematical Fellows, was to propose to the Board that it establish a School of Engineering. This received a favourable response and the Trinity Engineering School was established in 1841. A close relationship has always existed between the Schools of Mathematics and of Engineering.