He was an example of a man gifted by nature with high intellectual endowments improving those endowments by constant study, investigation, and reflection. An amount of professional labour, such as would have wearied many men, was daily performed by him; and from this he turned for relaxation to arduous chemical and mechanical researches. His mind was of that rare quality which is ever open to the reception of truth, and which steadily pursues that object, undismayed by difficulties, and indifferent alike to ridicule and neglect....L NEARLY thirty years after the death of the English physician and chemist, William Prout, Munk recorded in his Roll ofthe Royal College ofPhysicians:2 'I am not aware that any full and searching estimate of Dr. Prout's merits as a philosopher and chemist has yet appeared.' Munk's remark remains true today, for no definitive life of Prout has ever been written,3 and indeed, Munk's own sympathetic account is still the most readily available biographical source.4 Such neglect is surprising, for Prout's name is a familiar one in textbooks of chemistry and physics associated with the unitary hypothesis that the chemical elements possess atomic weights which are integral multiples of the atomic weight of hydrogen.5 He is otherwise featured in a minor way in histories of chemistry and medicine as the discoverer of hydrochloric acid in gastric juice, and as an early organic analyst.6 The purpose of the present essay is to attempt to provide a satisfactory account of Prout's intellectual life based upon contemporary sources, his own writings, and some information kindly given by his descendants. ' But see Kasich, A. H., Discovery of hydrochloric acid in gastric juice, Bull. Hist. Med., I 946, 20, 340-58. There are a few surviving letters (6 in the Royal Society, 2 in the Royal College of Physicians). Some of Prout's chemical notes have been recovered recently, and through the kindness of Lt.-Col. P. E. H. Warner they have been passed to me for examination. Fortunately-or unfortunately-they do not impel me to make any significant alterations to the present paper, although they considerably expand our knowledge of Prout's ideas on the nature of matter. A list of these papers, together with a few remarks, is now given. (i) 'Sketch of the History of Physic', 97 pp., dated Edinburgh, July I809 and described as 'Read August Io, I8o9'. An account of medical systems from Hippocrates until the end of the sixteenth century. The audience is not known. (2) 'Dissertatio de Sonis et Actione harmonia Auris humana', Edinburgh, i8iO, 39 pp. An undergraduate essay. (3) 'De Facultate Sentiendi', Edinburgh, I8Io, 26 pp., in English. This undergraduate essay sheds fresh light on the origins of Prout's Hypothesis. A full text will be published elsewhere. (4) Waste book consisting of abstracts of Prout's reading in animal and vegetable chemistry. Date circa I8I 2 to I814. (5) Notes and drafts for the Animal Chemistry Lectures of I814. With the exception of the introduction to these lectures, which relates to a theory...
