SKETCH OF DAVID HO SACK. 837 



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. Al- 

 though 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 spe- 

 cies to be found in that establishment. I also had the benefit 

 once a week of accompanying him in an excursion to the differ- 

 ent parts of the country in the vicinity of London. Dr. William 

 Babbington, Dr. Thornton, Dr. (now Sir) Smith Gibbs, Dr. Hun- 

 ter, 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 cryptoga- 

 mist, 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 Linnsean Society, Dr. (now Sir) James Edward 

 Smith ; and by the kindness of the same gentleman I had access 

 to the Linnsean Herbarium. I spent several hours daily for 

 four months examining the various genera and the most im- 

 portant species contained in that extensive collection." The ac- 

 quaintance 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 Trans- 

 actions 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 



