Of his sagacity, and the wonderful penetration with which he often discovered and described, at first sight of a patient, such distempers as betray themselves by no symptoms to common eyes, such wonderful relations have been spread over the world, as, though attested beyond doubt, can scarcely be credited. I mention none of them, because I have no opportunity of collecting testimonies, or distinguishing between those accounts which are well proved, and those which owe their rise to fiction and credulity. Yet I cannot but implore, with the greatest earnestness, such as have been conversant with this great man, that they will not so far neglect the common interest of mankind, as to suffer any of these circumstances to be lost to posterity. Men are generally idle, and ready to satisfy themselves, and intimidate the industry of others, by calling that impossible which is only difficult. The skill to which Boerhaave attained, by a long and unwearied observation of nature, ought, therefore, to be transmitted, in all its particulars, to future ages, that his successors may be ashamed to fall below him, and that none may hereafter excuse his ignorance, by pleading the impossibility of clearer knowledge. Yet so far was this great master from presumptuous confidence in his abilities, that, in his examinations of the sick, he was remarkably circumstantial and particular. He well knew that the originals of distempers are often at a distance from their visible effects; that to conjecture, where certainty may be obtained, is either vanity or negligence; and that life is not to be sacrificed, either to an affectation of quick discernment, or of crowded practice, but may be required, if trifled away, at the hand of the physician. About the middle of the year 1737, he felt the first approaches of that fatal illness that brought him to the grave, of which we have inserted an account, written by himself, Sept. 8, 1738, to a friend at London [38]; which deserves not only to be preserved, as an historical relation of the disease which deprived us of so great a man, but as a proof of his piety and resignation to the divine will. In this last illness, which was, to the last degree, lingering, painful, and afflictive, his constancy and firmness did not forsake him. He neither intermitted the necessary cares of life, nor forgot the proper preparations for death. Though dejection and lowness of spirits was, as he himself tells us, part of his distemper, yet even this, in some measure, gave way to that vigour, which the soul receives from a consciousness of innocence.