COCK LANE GHOST, a supposed apparition, the vagaries of which attracted extraordinary public attention in London during 1762. At a house in Cock Lane, Smithfield, tenanted by one Parsons, knockings and other noises were said to occur at night varied by the appearance of a luminous figure, alleged to be the ghost of a Mrs Kent who had died in the house some two years before. A thorough investigation revealed that Parsons' daughter, a child of eleven, was the source of the disturbance. The object of the Parsons family seems to have been to accuse the husband of the deceased woman of murdering her, with a view to blackmail. Parsons was prosecuted and condemned to the pillory. Among the crowds who visited the house was Dr Johnson, who was in consequence made the object of a scurrilous attack by the poet Charles Churchill in "The Ghost."
See A. Lang, _Cock Lane and Common Sense_ (1894).
COCKLE, SIR JAMES (1819-1895), English lawyer and mathematician, was born on the 14th of January 1819. He was the second son of James Cockle, a surgeon, of Great Oakley, Essex. Educated at Charterhouse and Trinity College, Cambridge, he entered the Middle Temple in 1838, practising as a special pleader in 1845 and being called in 1846. Joining the midland circuit, he acquired a good practice, and on the recommendation of Chief Justice Sir William Erle he was appointed chief justice of Queensland in 1863. He received the honour of knighthood in 1869, retired from the bench, and returned to England in 1879.
Cockle is more remembered for his mathematical and scientific investigations than as a lawyer. Like many young mathematicians he attacked the problem of resolving the higher algebraic equations, notwithstanding Abel's proof that a solution by radicles was impossible. In this field Cockle achieved some notable results, amongst which is his reproduction of Sir William R. Hamilton's modification of Abel's theorem. Algebraic forms were a favourite object of his studies, and he discovered and developed the theory of criticoids, or differential invariants; he also made contributions to the theory of differential equations. He displayed a keen interest in scientific societies. From 1863 to 1879 he was president of the Queensland Philosophical Society (now incorporated in the Royal Society of Queensland); on his return to England he became associated with the London Mathematical Society, of which he was president from 1886 to 1888, and the Royal Astronomical Society, serving as a member of the council from 1888 to 1892. He died in London on the 27th of January 1895.