his pursuit; he nevertheless did not neglect the collateral branches of medical science.
It was during this stay abroad that his interest in botany sprang up. "Having," as he says, "upon one occasion—while walking in the garden of Prof. Hamilton, at Blandford in the neighborhood of Edinburgh—been very much mortified by my ignorance of botany, with which his other guests were familiarly conversant, I had resolved at that time, whenever an opportunity might offer, to acquire a knowledge of that department of science. Such an opportunity was now presented, and I eagerly availed myself of it. The late Mr. William Curtis, author of the Flora Londinensis, had at that time just completed his botanic garden at Brompton, which was arranged in such a manner as to render it most instructive to those desirous of becoming acquainted with this ornamental and useful branch of a medical education. Although Mr. Curtis had for some time ceased to give lectures on botany, he very kindly undertook, at my solicitation, to instruct me in the elements of botanical science. For this purpose I visited the botanical garden daily throughout the summer, spending several hours in examining the various genera and species to be found in that establishment. I also had the benefit once a week of accompanying him in an excursion to the different parts of the country in the vicinity of London. Dr. William Babbington, Dr. Thornton, Dr. (now Sir) Smith Gibbs, Dr. Hunter, of New York, the Hon. Mr. Greville, and myself composed the class in these instructive botanical excursions, in the summer of 1793.
"By Mr. Dixon, of Covent Garden, the celebrated cryptogamist, the 'maximus in minimis,' as Mr. Curtis has very properly and facetiously denominated him, I was also initiated into the secrets of the cryptogamic class of plants. In the spring of 1794 I also attended the public lectures of botany delivered by the President of the Linnæan Society, Dr. (now Sir) James Edward Smith; and by the kindness of the same gentleman I had access to the Linnæan Herbarium. I spent several hours daily for four months examining the various genera and the most important species contained in that extensive collection." The acquaintance thus begun with Sir James Edward Smith ripened into an affectionate friendship, and a correspondence was begun that ended only with Smith's life.
In the course of the winter of 1793-'94 Dr. Hosack embodied certain Observations on Vision in a paper which he communicated to the Royal Society. It was published in the society's Transactions for 1794, and brought him, after due examination by a committee, the thanks of the society. A theory was in some vogue at the time that the power of accommodation in the eye
