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GEORGE PEARSON, M. D. F. R. S.
Few men of the present age have contributed more highly to the progress of science, of chemistry in particular, as well as of the practice of medicine on sound principles, than the amiable individual who is the subject of the following biographical Notice, for which we are principally indebted to the pages of “The Gentleman's Magazine.” Doctor Pearson was born in 1751, at Rotherham, in Yorkshire. His grandfather, Nathaniel, was for forty years Vicar of Stainton, in that neighbourhood; and died in 1767, at the age of 88. His uncle, George, after whom he was named, was a wine-merchant at Doncaster, for upwards of thirty years a member of the Corporation, and twice Mayor of the borough.* Being intended for the profession of medicine, he studied at Edinburgh and Leyden, and settled in early life in the practice of his profession in London. He was some years after elected Physician to St. George's Hospital; became a Fellow of the Royal Society in 1791, and was repeatedly chosen of the Council. Of the benefits which, during his long and active life, Doctor Pearson conferred on medical and general science, the following extract from the Address of the President of the Royal Society, at the anniversary meeting of the Society on the 1st of December, 1828, gives an elegant and comprehen
sive view : —
* The epitaphs of these individuals, at Stainton, may be seen in Hunter's “History of the Deanery of Doncaster,” vol. i. p. 258.
“Another distinguished member of this Society has recently been taken from us by one of those accidents, common, indeed, to old age, yet of a nature to excite compassion, or feelings, perhaps, of a stronger cast. Dr. George Pearson was elected in June, 1791, and has enriched our Transactions with ten communications. The first, in the year of his admission, on Dr. James's antimonial powders. The composition of this celebrated febrifuge having been long withholden from the public, notwithstanding the sworn specification of its inventor, a great anxiety was naturally felt for discovering the secret. This Doctor Pearson effected; having proved by analysis, and by the re-union of the constituent parts, that antimony and phosphate of lime made up the whole mass. Some slight difference may still exist between the concerted medicine and any other that can be produced, arising probably from peculiar and possibly accidental and unimportant manipulations; but no doubt can be entertained as to the essential ingredients. The second, in 1792, on the composition of fixed air. The third, in 1794, on a peculiar vegetable substance, imported from China. The fourth, in 1795, on the nature and properties of Wootz iron and steel made in the East Indies. The fifth, in 1796, in a paper equally interesting to the natural philosopher and to the antiquary, since it ascertains the composition of metallic weapons belonging to times the most remote, and confirms the opinion, derived from classical authority, of their being made from an alloy of copper and tin. The sixth, in 1797, on the nature of gas produced by passing electric sparks through water. This communication must be highly estimated, since it tended, at that early period, strongly to confirm the great discovery of Mr. Cavendish — the decomposition of water; a discovery of the utmost importance, but requiring every possible confirmation, as it went in direct opposition to the decided opinions, to the prejudices, of many hundred years. We are become familiar with hydrogen, with oxygen, with the compound nature of liquids, and the changes of form produced on bodies by the agency of heat. The speculative philosophers of antiquity, on the contrary, mistaking varieties of form for real differences of substance, arranged all physical mature under four classes, – denominating solid bodies, or the principle of solidity, earth; liquid bodies, under a similar hypothesis, water; and the principle of elasticity, air; fire, or heat, occupied the fourth division: and to these was added a fifth, or quintessence,—the substance endowed with consciousness, with thought, and with the power of originating motion. It is obvious that ice, water, and steam, to ratify this arrangement, must possess three distinct essences; yet such is the power of habitual attachment to opinions never before questioned, that had Mr. Cavendish, the scientific ornament of our country and of his age, lived some centuries before our time, he might, perhaps, have experienced a common fate with the philosopher who maintained the revolution of the earth, and the central position of the sun. The seventh, eighth, and ninth communications, in subsequent years, are strictly professional; and the tenth, in 1813, also medical, relates to a black colouring matter occasionally found in the bronchial glands. But Doctor Pearson has still farther claims on our respect and our regard. For a series of years he continued to diffuse, by his lectures, a knowledge of the new chemistry; instructing hundreds in the truths of science, as they became successively developed, in a manner not calculated to load the memory, but to invigorate the reasoning powers, in proportion as new facts were communicated and arranged. And to Doctor Pearson we are again indebted for rendering familiar in England the nomenclature of chemistry, first adopted in another country; an adaptation of words to things, of which it may be truly said,
A medium of communication adapting its plastic nature to the reception of new facts and of new arrangements, owing, perhaps, their existence to the facilities of their universal language.”
As a lecturer, Doctor Pearson was plain, distinct, comprehensive, and impressively energetic; and on many occasions he was argumentative, often witty, and even eloquent, when a favourite subject was the object of display. To his pupils he was kind and communicative, and even in his common conversation there was such a degree of deference and friendly (fatherly, we might say,) feeling to those who were attentive to him, that his pupils were generally much attached to him. His lectures on Therapeutics and Materia Medica were the most instructive at that period given in London; and he took great pains to point out, as far as was then ascertained, the principles of action of medicines, and their peculiar properties and doses. Thus far he went, preferring general principles to that cramped method of instruction, of giving prescriptions for supposed cases; since no two cases of diseases occur, corresponding in every distinctive symptom and particular. In some respects he may have been deemed eccentric; but, to make a long lecture on a dry subject appear short, as well as with the view of impressing it on the mind of his hearers, he frequently introduced anecdotes, often droll, yet generally possessed of some pithy meaning connected with the subject of lecture. The great and inestimable value of his lectures on the Practice of Physic was, that it rendered his pupils independent of the shackles of nosological forms, by teaching principles, or giving the outlines of diseases, to be filled up by future experience in practice. In his lectures on the principles of Medicine, and on the Practice of Physic, although he dwelt for a greater length of time than the generality of students like to devote to an abstruse and difficultly-acquired subject, yet there was much future practical good to be derived from his then supposed tiresomely tedious topic, “Excitability;” for it was calculated to impress principles productive to the hearer of the greatest benefit when, in after-life, at the bedside of sickness.
As regards chemistry, many of Doctor Pearson's early pupils are still attached to his grammar-like mode of teaching that science, by first instructing the pupil in the properties of simple substances; and, as the mind expanded, then the more complex union of simple substances, hinting at their affinities; and ultimately, when the student was in a state capable of comprehending them, pointing out the laws which govern chemical attraction.
His favourite subjects were Excitability: Cow-pox as a substitute for Small-pox; Fever; Diseases of the Lungs; Tubercles. In Chemistry, the decomposition and recomposition of Water; the decomposition of Carbonic Acid in Carbonates, and the separation of their Carbon; Steel, and its Carbon; Antimonial Powder of James; the proof that Alcohol exists in Wine, as a product of fermentation, and not of the process of distillation, by which it is separated.
Doctor Pearson had a habit, when much absorbed and very intent on his subject, or whenever he was more particularly desirous of recollecting a particular object or remarkable circumstance, of pushing up his spectacles, or of taking them off and on, holding them in one hand; and in this way he would repeat the same word or sentence many times, till at length his stores of “mental lore” were regularly assorted and found ready for delivery; he would then amply make up to his hearers for their lost time and patience, by going on in a powerful strain of energetic language, when he would, on a sudden recollection of the time, abruptly terminate his lecture by a favourite annunciation of “but more of this subject to-morrow, gentlemen.”
The following is an imperfect list of Doctor Pearson's publications : —
“Disputatio Physica Inauguralis, de Putridine Animalibus post Mortem superveniente. Edin. 1774,” 8vo.
“Observations and Experiments for investigating the Chemical History of the Tepid Springs of Buxton; intended for the Im
provement of Natural Science and the Art of Physic. Lond. 1783,” 2 vols. 8vo.