master-work on the HUMAN UNDERSTANDING, by Locke, which is still referred to as a standard in metaphysical science, and stands as a monument of the author's exalted genius. He says, "When we know our own strength, we shall the better know what to undertake with hopes of success. And when we have well surveyed the powers of our own minds, and made some estimate what we may expect from them, we shall not be inclined either to sit still, and not set our thoughts on work at all, in despair of knowing any thing; or, on the other side, question every thing, and declaim all knowledge, because some things are not to be understood. It is of great use to the sailor to know the length of his line, though he cannot fathom with it all the depths of the ocean. It is well he knows that it is long enough to reach the bottom at such places as are necessary to direct his voyage, and caution him against running upon shoals that may ruin him. This was that which gave the first rise to this Essay concerning the Understanding." The same may be affirmed of Newton. The same phenomena which were present to his mind, had been present for ages before to the minds of philosophers, and even to the senses of the vulgar. Every thing was the same to him and them, except the observing and reasoning mind. Here lay the difference:-conscious of his own powers and capabilities, he ventured where mind had never travelled. He took his ardent flight, and explored the secrets of creation with a success which left all preceding discoveries at an infinite distance. Before him, no one had even conjectured that the force which retains the planets in their orbits, is the same with that which occasions the fall of a pebble to the earth. As he took his upward flight and soared through the regions of light, at his approach each star blazed into a sun, and stood out as the centre of a harmonious system. To the activity of that one mind, science is under indefinite obligation. Ignorance of our own powers, is the greatest disqualification for effort. We shall attempt nothing till we are conscious of some intellectual strength. If it be essential to the perfection of some mechanical process that we know the powers of the instruments employed, it is no less necessary to the accomplishment of any intellectual effort, that we should have at least some knowledge of those internal phenomena on which such an effort depends ;— in other words, that we should not be ignorant of our minds. As a rational and intelligent being, man is capable of great and progressive improvement. His education does not end with his childhood. When he becomes a man, he may "put away childish things;" but he has still much to learn. The term of instruction is as extended as life itself. It matters not what are his relations and pursuits:-the voice of the oracle is to advance. In ancient Greece and Rome, there were the gymnasia, or public buildings, in which young men were trained in athletic exercises, and thus qualified for the public games. We would have each young man convert his room into a gymnasium, and subject his mind to a sound and wholesome discipline. If health may be preserved and promoted by the gymnastics of more modern times, the vigour of mind and intellect may largely benefit under such a regime as we now propose. Mind should be so trained and disciplined as to bring out its capabilities of thought and reflection. Only induce the habit of thought, and improvement will be certain, rapid, delightful. One idea will lead to the pursuit and possession of another. It will then be painful not to know, or even to know imperfectly. The soul will thirst for knowledge. No common draught will satisfy it. The desire once created, the mind will become insatiable. A spring in the desert may revive and refresh the traveller on his way; but before he has advanced another stage in his progress, how intense is his desire for the next living stream. So it is in the acquisition of knowledge. Thought begets thought. There is a continued progression. If "the eye is not satisfied with seeing, nor the ear with hearing," neither is the mind with partial or limited information. Onward it moves. No power can arrest its progress:—no voice speaks it back, saying," Hitherto shalt thou come, and no farther." It surmounts every obstacle:-it forces its way through every difficulty. Having started in the race of improvement, it " presses toward the mark❞—it looks to the goal-it covets the prize. We would not conceal the fact, that there is a limit to the powers of the mind. What is created is finite. The human intellect may be equal to indefinite efforts; but there is a point beyond which it cannot be exerted. It would then be unwise to lay these powers under full contribution. If too severe or over-much exercise may induce physical disease, any unusual exertion of mind might rather endanger or paralyse its powers. If gymnastics are to be of any avail in promoting health and muscular power, it must be in their judicious selection, and in their adaptation to the physical circumstances of the individual. So it must be in the exercise of mind. We would have you put forth its strength, but not to attempt what is clearly without its grasp and beyond its power. Never suppose that you are not equal to some effort. Never entertain the idea that your minds are not competent to this subject, or to that effort. Mind strengthens by exercise. Your first attempt may be feeble. Your second will be less so; and so the third, and every successive effort, till you will be no longer conscious of mental weakness or intellectual inaptitude. In beginning this intellectual training, let your thoughts run out at first on what is comparatively simple and obvious. Be not anxious to overtake too much. Better seize on a single idea, and so work it into your mind by patient examination and thought as to make it a part of your mental nature, than peruse a volume without attempting to lay hold of any great principle or truth with which it may be enriched. Mental possession is not to be obtained, any more than the gains of time, without patient application and perseverance. One thought will outweigh a world. It is indestructible-imperishable. The property and possessions of earth are temporary and passing,-thought is as enduring as the soul. The law of immortality is impressed upon our whole nature. We have entered on an existence which is to run parallel with the existence of God: "O what a patrimony this!—a being Of such inherent strength and majesty, Not worlds possess'd can raise it,-worlds destroy'd And through the perpetuity of being, thought will be inseparable from mind. The future is a world of intelligence. While we exist we shall think. The powers and capabilities which we now possess will there still unfold and expand. Heaven is a place of ceaseless activity. Among the myriads who there reside, there is not one who is not actively and constantly employed. There sloth has no existence. Fatigue never overtakes the powers of any mind. Onward they move, and onward they will con tinue to move, "while being lasts and immortality endures." New fields of investigation will open before us-unmeasured and immeasurable. The materials with which these fields are replenished are literally inexhaustible; and therefore the progress of mind in discovery and knowledge will be everlasting. There intelligence and virtue, truth and piety, will advance together-for ever enlarging, refining, elevating, and abiding. To what are these noble powers devoted? What engages these vast capabilities of soul? How often is mind prostituted,-its vigour impaired, its faculties paralysed,-its glory trampled in the dust! What prostration of man do we see around us! How few, comparatively, stand up in the erectness of a perfect manhood! They cultivate not their powers. They make no effort-have no ambition to rise in their intellectual and moral being. We may tell them that man was originally formed for endless improvement; that his mind, like that of angels, was capable of coutinued expansion, refinement, and elevation; and that He who gave immortal life and youth to man at first, with the communication of spiritual knowledge, refined affections, and spotless purity, has promised to communicate the same to us has opened the path to their attainment—has again planted in this our world the tree of knowledge-the tree of life, and bids us eat that we may live. They care not. They have no taste for the intellectual and the spiritual. The study of mind-the cultivation of the intellect, they deem worse than useless. They aim at nothing higher than the knowledge of business, and the secrets of wealth. They would rather be rich than intelligent-rather be worldly great, than morally good. Let yours be a nobler ambition. Neither wealth nor distinction is to be depreciated. Both may be the object of lawful and honourable pursuit. We would have you employ every means to advance your present interests. Still, these are subordinate. "With all your getting, get understanding." "Wisdom is a defence, and money is a defence; but the excellency of knowledge is, that wisdom giveth life to them that have it." "But where shall wisdom be found? and where is the place of understanding? Man knoweth not the price thereof; neither is it found in the land of the living. The depth saith-It is not in me: and the sea saith-It is not with me. It cannot be gotten for gold, neither shall silver be weighed for the price thereof. It cannot be valued with the gold of Ophir, with the precious onyx, or the sapphire. The gold and the crystal cannot equal it: and the exchange of it shall not be for jewels of fine gold. No mention shall be made of coral, or of pearls: for the price of wisdom is above rubies. The topaz of Ethiopia shall not equal it, neither shall it be valued with pure gold." [This article is a mere introduction to a series of papers on this very interesting and important subject, which will appear regularly each month. The next article will be on THE SOURCES OF INFORMATION.] THE UPAS," horribilius ac detestabilius toxicum, quod ab ullo producitur vegetabili, quam quod ex hac lactescente colligitur arbore," as it is styled by Rumphius, derives its interest chiefly from the gross literary frauds with which its name will ever be connected; so that in the present paper we shall do little more than offer a brief historical account of the plant to our readers. Most of the earlier travellers who visited the Indian Archipelago, allude to the existence of a poisonous tree growing in the Celebes, the exudation from which is described as of a most deadly nature. Thus, Sir Thomas Herbert,† when speaking of the Macassers, says :-"The men use long canes or trunks called sempitans, out of which they blow a little pricking quill, which if it draw the least drop of blood, it destroys immediately. Some venoms operate in an hour; others in a moment; the veins and body (by the virulency of the poison) corrupting and rotting presently, even to terrour and amazement." Numerous accounts of the tree were published subsequently to this period, by Tavernier, Nieuhoff, Spielmann, Kæmpfer, Rumphius, and others; but it attracted little attention from the public until an article appeared in the London Magazine for December, 1783, which was stated to be a translation by Heydinger, "formerly a German book * This sketch is reduced from Blume's Rumphia. Some Yeares Travels into Africa and Asia the Great, 1677. seller near Temple-bar," from the Dutch of Forsch, a surgeon stationed at Batavia. During his residence there, his curiosity being greatly excited by the various statements he received respecting the Bohun-Upas, as it is termed in the Malay language, he resolved to investigate the subject for himself. Having accordingly procured a pass to travel through the country from the Governor-general, and an introduction to an old priest who resided at the nearest habitable spot to the tree, and prepared for eternity the souls of those malefactors that preferred the attempt of procuring the poison, to the certainty of a public execution, he made the tour all around the dangerous spot, at about eighteen miles distant from the centre, and found the land entirely barren on all sides,-not even the least plant or grass to be seen. He states that each criminal was sent to the house of the old ecclesiastic, and furnished with a box for the poison, a long leather-cap, and a pair of leather-gloves, and instructions were given him to travel with the utmost dispatch, and always before the wind. During thirty years, the priest assured Forsch that he had dismissed upwards of seven hundred criminals, but that scarcely two out of twenty returned. When questioned about the origin of the tree, he replied:-"We are told in our new Alcoran that above a hundred years ago, the country around the tree was inhabited by a people strongly addicted to the sins of Sodom and Gomorrah; when the great prophet Mahomet determined not to suffer them to lead such detestable lives any longer, he applied to God to punish them; upon which God caused this tree to grow out of the earth, which destroyed them all, and rendered the country for ever uninhabitable." Forsch also states, that in consequence of a rebellion in 1755, four hundred families were compelled to settle in the uncultivated vicinity of the tree; but their number, in less than two months, was reduced to about three hundred, all of whom had the appearance of being tainted with an infectious poison. A description is likewise given of the execution of thirteen fair delinquents, in all of whom life was extinct sixteen minutes after they had been lanced in their breasts by an instrument poisoned with the gum of the Upas. Some hours after death, he observed their bodies full of livid spots, their faces swelled, their colour changed to a kind of blue, their eyes yellow, &c. This account afforded to Darwin too excellent a subject for poetic embellishment, to render him anxious to investigate its authenticity with any very great degree of severity; his personification of the tree, indeed, in the Loves of the Plants, may be well ranked amongst the most beautiful and striking passages in the whole poem : "Fierce in dread silence on the blasted heath |