tinction and definition of particular diseases, or of the genera and species of diseases; 2dly, The nomenclature of diseases, or the assignment of the names by which they are to be designated; and, 3dly, The arrangement or classification of diseases in some methodic and convenient order. The first of these objects of nosology, -the distinction and definition of particular diseases, -Dr Cullen regarded as being by far the most important; and it was to its improvement that his efforts were at all times chiefly directed. The circumstance of his having been engaged, for a long series of years, in delivering lectures, first, on the Practice of Physic in the University of Glasgow, and subsequently on Clinical Medicine in Edinburgh, had necessarily served to direct his attention in a particular manner to the examination of those characters by which diseases may be most easily and accurately distinguished from one another, not only as an object of interesting speculation, and of immediate practical importance, but also as affording a means of facilitating the teaching and the study of medicine. And his intimate acquaintance with the rules of Logic, as well as the attention which he had bestowed upon the different branches of Natural History, by familiarising him with the principles upon which logicians and naturalists respectively distinguish different objects from one another, formed, when conjoined with the extensive practical knowledge of the phenomena of diseases which he possessed, the best possible preparation for an attempt to extend these principles to Nosology.*

It is interesting to learn that, at the very time when the subject of Methodical Nosology in a particular manner occupied his

It appears from several passages in Dr Cullen's correspondence and manuscript lectures, that his attention was drawn in a very particular manner to the study of Nosology by the publication of M. Sauvages' Nosologia Methodica, at Montpellier, in 1763; for, soon after this period, he manifests, in his correspondence with his pupils, a desire to ascertain the opinions which other physicians had formed respecting the utility of a plan of Methodical Nosology, such as that followed in Sauvages' work. Thus, in a letter written by him in 1764 to his pupil Dr David Millar, who was then in London, he says,-"Let me know if any body at London has read Sauvages' Nosologia Methodica; or if any body enters into such a plan, or approves of others doing it ;" and it appears by a letter from his former pupil Dr Dobson of Liverpool, dated October 1764,

thoughts, Dr Cullen was engaged in studying, with great zeal, the characters by which minerals are distinguishable from one another. This appears from a passage in a preface, prefixed by the late Dr Walker, professor of Natural History in the University of Edinburgh, to a catalogue of the minerals contained in the University Museum. In the year 1764, Dr Walker made a tour through the Highlands of Scotland, by order of the General Assembly of the Church, for the purpose of inquiring into the state of the parochial schools in these districts. "Not long before I set out," says he, in the preface referred to, " Dr Cullen had received the first German edition of Cronstedt's Essay towards a system of Mineralogy, of which he was so fond, that he carried it several weeks in his pocket. He translated to me out of it the leading characters of Cronstedt's new and peculiar classes. He was particularly anxious," adds Dr Walker, "about the Zeolite; and it was in consequence of this that I first observed it among the basaltic rocks at the Giant's Causeway, and afterwards, in greater plenty and variety, in many of the Islands." (See Appendix A.)

that the attention of that physician, likewise, had been directed to this subject by Dr Cullen about the same period. (See Appendix B.)

In a clinical lecture, delivered in January 1765, Dr Cullen gave a short but comprehensive view of the principles of Nosology, and an account of the labours of Sauvages in this department; and he continued, after this, to refer constantly in his clinical lectures to the definitions which that distinguished author had given of diseases, till the publication of the first edition of his own Synopsis. In the short course of lectures on the Practice of Physic which he delivered, with Dr Gregory's permission, in the summer of 1768 (vol. i. p. 161), he gave an introductory lecture on the distribution or arrangement of diseases, in which he mentioned his having printed a synopsis of the three methods of Sauvages, Linnæus, and Vogel. As this course was addressed to a class of advanced students, Dr Cullen found himself at liberty to enter on a comparison and critical examination of the higher divisions of Classes and Orders which these nosologists had established. In concluding this review, he remarks,— "These are the faults in the systems hitherto given. I must now offer you another. The matter is so difficult that I have hesitated much about making an attempt; but I hazard something to be useful, and an imperfect attempt is allowable here, though not fit to be offered to the public. As it is now given out, it is to be regarded as a sketch not finished."

Into the first edition of his Nosology, published in the subsequent year (1769), Dr Cullen introduced the definitions of the genera of diseases that had been given

by Sauvages, Linnæus, and Vogel, together with the attempt he had himself made to simplify the classifications they had proposed, and to give fuller and more accurate definitions of at least the principal genera of diseases. In an address to his pupils, prefixed to this edition, after stating generally the objects and nature of the work, he remarked, that, notwithstanding the valuable labours of his predecessors in this department, it was not to be supposed that Nosology was yet in a perfect state, or that it would be improved in any other way than by repeated attempts and by much labour and time;-that in the attempt which he had himself made to improve the characters of diseases, he had bestowed more pains on those of Universal, than on those of Local diseases, which latter class he had considered only in a superficial manner;-and that he was aware he had left many things imperfect, but he hoped to be able to explain and to vindicate those matters which might appear incorrect or doubtful.

Two years afterwards (in 1771), when it was again Dr Cullen's turn to deliver the practical course, he published a second edition of his Nosology. Besides endeavouring, in this edition, to improve the definitions of the classes, orders, and genera of diseases, he added, under his own genera, a list of, and references to, the principal species enumerated by Sauvages; and prefixed to his own part of the work a preface entirely

new.

A third and carefully revised edition of Dr Cullen's Nosology appeared in 1780; but it is the fourth edition, published in two volumes 8vo, in 1785, which contains

the last corrections of the author, and exhibits his nosological labours in their most finished form. Into the third edition he introduced, besides the classifications of Sauvages, Linnæus, and Vogel, already mentioned, that of Sagar, as contained in his Systema Morborum Systematicum, published at Vienna in 1771; and into the fourth, that of Dr Macbride, as contained in his Methodical Introduction to the Theory and Practice of Physic, published at London in 1772. Numerous reprints of these different editions of Dr Cullen's Nosology appeared upon the Continent, particularly in Holland, Germany, and Italy.

Though Dr Cullen's Synopsis was, on the whole, very favourably received by the medical public, yet, by some very distinguished physicians, the study of Nosology, when first introduced by him into this country, was considered as a frivolous and unattainable pursuit. His favourite pupil, Dr Monro Drummond, in writing to him from London, 14th December 1771, says, "So far as I know, Sir John Pringle thinks the properties of diseases to be such as render them incapable of those methodical and strict arrangements which are applicable to plants; and the modern Nosology, in consequence, fanciful and useless; and not only so, but hurtful also, by fixing the mind on the circumstance of collocation merely, and detaching it from more accurate investigations into what is in general so little known, the thing itself to be placed. This I never heard him express myself in so many words; but from what I have heard him say, and have learned from others, such, I collect, is the opinion he entertains. Ac