ny, willing to distinguish himself by his zeal, instead of confuting the positions of Spinosa by argument, began to give a loose to contumelious language, and virulent invectives, which Boerhaave was so little pleased with, that at last he could not forbear asking him whether he had ever read the author he declaimed against.

The orator, not being able to make much answer, was checked in the midst of his invectives, but not without feeling a secret resentment against the person who had at once interrupted his harangue, and exposed his ignorance.

This was observed by a stranger who was in the boat with them; he enquired of his neighbour the name of the young man, whose question had put an end to the discourse, and having learned it, set it down in his pocket-book, as it appears, with a malicious design, for in a few days it was the common conversation at Leyden, that Boerhaave had revolted to Spinosa.

It was in vain that his advocates and friends pleaded his learned and unanswerable confutation of all atheistical opinions, and particularly of the system of Spinosa, in his discourse of the distinction between soul and body. Such calumnies are not easily suppressed, when they are once become general. They are kept alive and supported by the malice of bad, and sometimes by the zeal of good men, who, though they do not absolutely believe them, think it yet the securest method to keep not only guilty, but suspected men out of publick employments, upon this principle, that the safety of many is to be preferred before the advantage of few.

Boerhaave, finding this formidable opposition

raised against his pretensions to ecclesiastical honours or preferments, and even against his design of assuming the character of a divine, thought it neither necessary nor prudent to struggle with the torrent of popular prejudice, as he was equally qualified for a profession, not indeed of equal dignity or importance, but which must undoubtedly claim the second place among those which are of the greatest benefit to mankind.

He therefore applied himself to his medical studies with new ardour and alacrity, reviewed all his former observations and enquiries, and was continually employed in making new acquisitions.

Having now qualified himself for the practice of physick, he began to visit patients, but without that encouragement which others, not equally deserving, have sometimes met with. His business was, at first, not great, and his circumstances by no means easy; but still, superior to any discouragement, he continued his search after knowledge, and determined that prosperity, if ever he was to enjoy it, should be the consequence not of mean art, or disingenuous solicitations, but of real merit, and solid learning.

His steady adherence to his resolutions appears yet more plainly from this circumstance: he was, while he yet remained in this unpleasing situation, invited by one of the first favourites of King William III. to settle at the Hague, upon very advantageous conditions; but declined the offer. For having no ambition but after knowledge, he was desirous of living at liberty, without any restraint upon his looks, his thoughts, or his tongue, and at the utmost distance from all contentions, and state

parties. His time was wholly taken up in visiting the sick, studying, making chemical experiments, searching into every part of medicine with the utmost diligence, teaching the mathematicks, and reading the scriptures, and those authors who profess to teach a certain method of loving God*.

This was his method of living to the year 1701, when he was recommended by Van Berg to the university, as a proper person to succeed Drelincurtius in the professorship of physick, and elected without any solicitations on his part, and almost without his consent, on the 18th of May.

On this occasion, having observed, with grief, that Hippocrates, whom he regarded not only as the father but as the prince of physicians, was not sufficiently read or esteemed by young students, he pronounced an oration, " de commendando Studio Hippocratico;" by which he restored that great author to his just and ancient reputation.

He now began to read publick lectures with great applause, and was prevailed upon by his audience. to enlarge his original design, and instruct them in chemistry.

This he undertook, not only to the great advan

"Circa hoc tempus, lautis conditionibus, lautioribus promissis, invitatus, plus vice simplici, a viro primariæ dignationis, qui gratia flagrantissima florebat regis Gulielmi III. ut Hagam comitum sedem caperet fortunarum, declinavit constans. Contentus videlicet vità libera, remota a turbis, studiisque porro percolendis unice impensa, ubi non cogeretur alia dicere et simulare, alia sentire et dissimulare: affectuum studiis rapi, regi. Sic tum vita erat, ægros visere, mox domi in musao se condere, officinam Vulcaniam exercere; omnes medicinæ partes acerrime persequi; mathematica etiam aliis tradere; sacra legere, et auctores qui profitentur docere rationem certam amandi Deum. Orig. Edit.

tage of his pupils, but to the great improvement of the art itself, which had hitherto been treated only in a confused and irregular manner, and was little more than a history of particular experiments, not reduced to certain principles, nor connected one with another: this vast chaos he reduced to order, and made that clear and easy, which was before to the last degree difficult and obscure.

His reputation now began to bear some proportion to his merit, and extended itself to distant universities; so that, in 1703, the professorship of physick being vacant at Groningen, he was invited thither; but he refused to leave Leyden, and chose to continue his present course of life.

This invitation and refusal being related to the governors of the university of Leyden, they had so grateful a sense of his regard for them, that they immediately voted an honorary increase of his salary, and promised him the first professorship that should be vacant.

On this occasion he pronounced an oration upon the use of mechanicks in the science of physick, in which he endeavoured to recommend a rational and mathematical enquiry into the causes of diseases, and the structure of bodies; and to shew the follies and weaknesses of the jargon introduced by Paracelsus, Helmont, and other chemical enthusiasts, who have obtruded upon the world the most airy dreams, and instead of enlightening their readers with explications of nature, have darkened the plainest appearances, and bewildered mankind in error and obscurity.

Boerhaave had now for nine years read physical lectures, but without the title or dignity of a professor, when, by the death of professor Hotten, the

professorship of physick and botany fell to him of

course.

On this occasion he asserted the simplicity and facility of the science of physick, in opposition to those that think obscurity contributes to the dignity of learning, and that to be admired it is necessary not to be understood.

His profession of botany made it part of his duty to superintend the physical garden, which improved so much by the immense number of new plants which he procured, that it was enlarged to twice its original extent.

In 1714, he was deservedly advanced to the highest dignities of the university, and in the same year made physician of St. Augustin's hospital, in Leyden, into which the students are admitted twice a-week, to learn the practice of physick.

This was of equal advantage to the sick and to the students, for the success of his practice was the best demonstration of the soundness of his principles.

When he laid down his office of governor of the university, in 1715, he made an oration upon the subject of "attaining to certainty in natural philosophy;" in which he declares, in the strongest terms, in favour of experimental knowledge, and reflects, with just severity, upon those arrogant philosophers, who are too easily disgusted with the slow methods of obtaining true notions by frequent experiments, and who, possessed with too high an opinion of their own abilities, rather chuse to consult their own imaginations, than enquire into nature, and are better pleased with the charming amusement of forming hypotheses, than the toilsome drudgery of making observations.