Nihell (Nihil), James (1705–59), physician and author, was born in Limerick, second son among five sons and four daughters of Laurence Nihell, merchant, and Alice Nihell (née Arthur). He was educated in France at the Jesuit Collège Royale de la Flèche, near Le Mans, and studied medicine possibly at Montpellier and Paris. His hopes of succeeding his uncle, Sir John Higgins (qv), physician to Philip V of Spain, were dashed by Higgins's sudden death (1729) while Nihell was en route to Madrid to visit him; and Nihell continued his studies at the universities of Leyden and Rheims, graduating Doctor of Medicine (MD) (1733).
He then established a practice in Spain and served (c.1736–9) as physician to the British Factory in Cadiz, the leading trading centre in Spain. Over this three-year period, he monitored indoor temperatures by means of the newly invented Fahrenheit thermometer and recorded them in his ‘Thermometrical journal’; the first known instrumental meteorological records made in the city, they comprise some of the earliest examples of scientific records of monthly and annual ranges of temperature.
Intrigued by the treatise Lapis Lydos Appollinis (Madrid, 1731) by Dr Francisco Solano de Luque (1658–1738), which claimed that crises of sweat, diarrhoea and haemorrhage could be predicted by the frequency of pulse intermissions, Nihell spent two months (1737) collaborating with Solano at Antequera, near Malaga, and encouraged him to prepare a new succinct edition of his work. Convinced of the value of Solano's work, Nihell returned to Cadiz and undertook further research, for ‘nothing is more common than mistaken inferences from undeniable data’, and he suspected that Solano had made ‘his rules too absolute and extensive’ (Mitchell, 47). After Solano's death (1738), his failure to purchase the draft of the work, its subsequent loss, and the interruption of his own clinical studies due to the death of a colleague, Nihell settled in London and published New and extraordinary observations concerning the prediction of the various crises by the pulse … made first by Dr Don Francisco Solano de Luque (1741), which included a summary of his ‘Thermometrical journal’. Dedicated by permission to the king's physician, Richard Mead (1673–1754), Nihell described Solano's work and his own observations; while aware that the results were not conclusive, he hoped that publication would stimulate research, and invited collaboration with fellow physicians, since the subject was ‘greatly superior to the diligence of any one man’ (Mitchell, 49). His treatise, which demonstrates a familiarity with empirical methods, was well received by his contemporaries in England and abroad as a significant contribution to medical knowledge; it was translated into Latin and French and reprinted several times (1744–78) and Nihell was elected fellow of the Royal Society (FRS) in 1742. A copy of his book in the British Library (BL) bears the inscription to his fellow countryman and president of the Royal Society, ‘To Sir Hans Sloan [qv] by his humble servant James Nihell’.
At the time of his death he was writing a ‘Historical and critical tract on the practice of physic’, on ‘Weather, air, situations etc.’, and had completed two-thirds of the ‘Life and doctrines of Christ’. His younger brother Laurence Nihell (1726–95), catholic bishop of Kilfenora and Kilmacduagh and author of Rational self love (1770) and other works, had planned to publish this work, after writing an introduction, under the title Historical … reflections on the redemption of man, but died before it was completed. James Nihell's work, which cannot be precisely identified in a manuscript of 900 folio pages, is preserved in St Ignatius's Residence, Lower Leeson Street, Dublin.
Cheerful, benevolent, respected in his profession for his wide learning and service to the poor, according to his obituarist, ‘his humility was superior from a just impression of the vanity of mere science, and the necessity of practical virtue’ (Public Gazeteer). He died in Limerick 12 May 1759; his burial place is not known.