In proceeding to give some account of his works, we must be necessarily more brief than a scientific analysis would require. To do him full justice, it would be necessary to republish his writings, with appropriate commentaries. We shall hope, however, to do enough to relieve his memory from some of the numerous misconceptions of his principles and opinions; and to endeavour to show his claims to the respect and gratitude of posterity. In everything Abernethy did, we find evidence of the acuteness of his mind, and his general qualifications for philosophical research. His lectures had gradually attracted an increasing number of students; and he seems, about 1791, to have been desirous of prefacing his lectures on Anatomy by discussing the general composition of Animal Matter. The rapid advance of chemistry had given a great impetus to this kind of investigation. Abernethy was not only well up in the chemistry of the day, but also not unskilled in the manipulatory application of it; and he felt interested in observing the great diversity of substances which appeared to be made up of similar elements. Boyle has recorded a vast number of facts, many of which would even now well repay a thoughtful revision; and Fordyce was certainly one of our most philosophical physicians. Boyle had grown vegetables in water and air only, and found they produced woody fibre. Fordyce found that gold fish, placed under similar conditions, not only lived, but _grew_. Abernethy's experiments had for their object to inquire how far organized bodies (animals and vegetables) were capable of deriving their various structures from similar simple elements. He grew vegetables on flannel, wetted from time to time with distilled water; and then, analyzing them, compared the results with those of the analysis of vegetables grown in the ordinary manner. Other curious experiments consisted in pouring concentrated acids on vegetable structures, with a view to dissolve any alkali or iron which they might contain, and then analyzing the vegetables so treated. He now found, in the burnt vegetable, lime, iron, &c. which, had they been free to combine, should have been taken up by the acid to which he had subjected the vegetable before he analyzed it; but he found neither in the _acid_, whilst both were discovered in the _vegetables_.