HANNIBAL TO HIS SOLDIERS. KNOW not, soldiers, whether you or your prisoners be encompassed by Fortune with the stricter bonds and necessities. Two seas enclose you on the right and left; not a ship to flee to for escaping. Before you is the Po, a river broader and more rapid than the Rhone; behind you are the Alps, over which, even when your numbers were undiminished, you were hardly able to force a passage. Here, then, soldiers, you must either conquer or die the very first hour you meet the enemy. But the same fortune which has laid you under the necessity of fighting has set before your eyes those rewards of victory than which no men are ever wont to wish for greater from the immortal gods. Should we by our valor recover only Sicily and Sardinia, which were ravished from our fathers, those would be no inconsiderable prizes. Yet what are these? The wealth of Rome, whatever riches she has heaped together in the spoils of nations, all these, with the masters of them, will be yours. You have been long enough employed in driving the cattle upon the vast mountains of Lusitania and Celtiberia; you have hitherto met with no reward worthy the labors and dangers you have undergone. The time is now come to reap the full recompense of your toilsome marches over so many mountains and rivers and through so many nations, all of them in arms. your This is the place which Fortune has appointed to be the limits of your labors; it is here that you will finish your glorious warfare and receive an ample recompense of completed service. For I would not have you imagine that victory will be as difficult as the name of a Roman war is great and sounding. It has often happened that a despised enemy has given a bloody battle, and the most renowned kings and nations have by a small force been overthrown. And if you but take away the glitter of the Roman name, what is there wherein they may stand in competition with you? For-to say nothing of your service in war for twenty years together with so much valor and success-from the very Pillars of Hercules, from the ocean, from the utmost bounds of the earth, through so many warlike nations of Spain and Gaul, are you not come hither victorious? And with whom are you now to fight? With raw soldiers, an undisciplined army, beaten, vanquished, besieged by the Gauls the very last summer, an army unknown. to their leader and unacquainted with him. Or shall I, who was born, I might almost say, but certainly-brought up in the tent of my father, that most excellent general; shall I, the conqueror of Spain and Gaul, and not only of the Alpine nations, but, which is greater yet, of the Alps themselves, shall I compare myself with this half-year captain?-a captain before whom should one place the two armies without their ensigns, I am persuaded he would not know to which of them he is consul. I es 66 You would have Spain too? Well, we shall yield Spain; and then you will pass into Africa. Will pass," did I say? This very year they ordered one of their consuls into Africa; the other, into Spain. tem it no small advantage, soldiers, that | dinia? On what side soever I turn my eyes, I behold all full of courage and strength-a veteran infantry; a most gallant cavalry; you, my allies, most faithful and valiant; you, Carthaginians, whom not only your country's cause, but the justest anger, impels to battle. The hope, the courage, of assailants is always greater than of those who act upon the defensive. With hostile banners displayed you are come down upon Italy; you bring the war. Grief, injuries, indignities, fire your minds and spur you forward to revenge. First they demanded me—that I, your general, should be delivered up to them; next all of you, who had fought at the siege of Saguntum; and we were to be put to death by the extremest tortures. Proud and cruel nation! Everything must be yours and at your disposal. You are to prescribe to us with whom we shall make war, with whom we shall make peace! You are to set us bounds, to shut us up within hills and rivers, but you—you are not to observe the limits which yourselves have fixed! Pass not the Iberus." What next? "Touch not the Saguntines." Saguntum is upon the Iberus. "Move not a step toward that city." Is it a small matter, then, that you have deprived us of our ancient possessions, Sicily and Sar No, soldiers, there is nothing left for us but what we can vindicate with our swords. Come on, then! Be men! The Romans may with more safety be cowards. They have their own country behind them, have places of refuge to flee to, and are secure from danger in the roads thither; but for you there is no middle fortune between death and victory. Let this be but well fixed in your minds, and once again, I say, you are conquerors. BOOKS. TITUS LIVIUS. (Livy.) that most interesting and instructive to Boswell's Life book Boswell's Life of Johnson an incident is mentioned which I beg leave to quote in illustration of this part of my subject. The doctor and his biographer were going down the Thames in a boat to Greenwich, and the conversation turned upon the benefits of learning, which Dr. Johnson maintained to be of use to all men. "And yet,' said Boswell, 'people go through the world very well, and carry on the business of life to good advantage, without learning.' 666 Why, sir,' replied Dr. Johnson, that may be true in cases where learning cannot possibly be of any use; for instance, this boy rows us as well without learning as if he could sing the song of Orpheus to the Argonauts, who were the first sailors.' He then called to the boy, 'What would you give my lad, to know about the Argonauts?' 666 'Sir,' said the boy, 'I would give what | single hour than the sun in his whole day's I have.' circuit. The poet's visions of evening are "Johnson was much pleased with this an- all compact of tender and soothing images. swer, and we gave him a double fare. "Dr. Johnson then turning to me, 'Sir,' said he, 'a desire of knowledge is the natural feeling of mankind, and every human being whose mind is not debauched will be willing to give all that he has to get knowledge.'" For the knowledge that comes from books I would claim no more than it is fairly entitled to. I am well aware that there is no inevitable connection between intellectual cultivation, on the one hand, and individual virtue or social well-being on the other. "The tree of knowledge is not the tree of life." I admit that genius and learning are sometimes found in combination with gross vices and not unfrequently with contemptible weaknesses, and that a community at once cultivated and corrupt is no impossible monster. But it is no overstatement to say that, other things being equal, the man who has the greatest amount of intellectual resources is in the least danger from inferior temptations-if for no other reason, because he has fewer idle moments. The ruin of most men dates from some vacant hour. Occupation is the armor of the soul, and the train of Idleness is borne up by all the vices. I remember a satirical poem in which the devil is represented as fishing for men and adapting his baits to the tastes and temperament of his prey; but the idler, he said, pleased him most, because he bit the naked hook. To a young man away from home, friendless and forlorn in a great city, the hours of peril are those between sunset and bedtime, for the moon and stars see more of evil in a It brings the wanderer to his home, the child to his mother's arms, the ox to his stall and the weary laborer to his rest. But to the gentle-hearted youth who is thrown upon the rocks of a pitiless city, and stands "homeless amid a thousand homes," the approach of evening brings with it an aching sense of loneliness and desolation which comes down upon the spirit like darkness upon the earth. In this mood his best impulses become a snare to him, and he is led astray because he is social, affectionate, sympathetic and warmhearted. If there be a young man thus circumstanced within the sound of my voice, let me say to him that books are the friends of the friendless, and that a library is the home of the homeless. A taste for reading will always carry you into the best possible company and enable you to converse with men who will instruct you by their wisdom and charm you by their wit, who will soothe you when fretted, refresh you when weary, counsel you when perplexed, and sympathize with you at all times. Evil spirits, in the Middle Ages, were exorcised and driven away by bell, book and candle; you want but two of these agents-the book and the candle. GEORGE S. HILLARD. AFFECTION. OH, cast thou not Affection from thee! In this bitter world Hold to thy heart that only treasure fast; Watch, guard it; suffer not a breath to dim The bright gem's purity. FELICIA HEMANS. T HEAT A MODE OF MOTION. SELECTED FROM LECTURES ON HEAT. HE aspects of Nature provoke The human mind began its operations among the powers of Nature, winning first a little knowledge and a little strength, and then turning the knowledge and the strength so won back upon Nature, with the view of winning more. Action and reaction have thus gone on from prehistoric ages to the present time. The result is that stored body of scientific knowledge and that developed power of scientific investigation which have revolutionized philosophy and begotten those marvels of practical science in the midst of which we dwell. Whenever friction is overcome heat is produced, and the heat produced is the exact measure of the power expended in overcoming the friction. The heat is simply the original power in another form; and if we wish to postpone this conversion, we must abolish the friction. We place oil upon the surface of a hone, we grease a saw and we are careful to lubricate the axles of our railway carriages. What is the real meaning of these acts? It is the object of a railway engineer to urge his train from one place to another, and it is not his interest to allow any portion of his force to be applied in a manner which would not promote the attainment of his object. He does not want his axles heated, and hence he avoids as much as possible expending his power in heating them. He has obtained his force from heat, and it is not his object to reconvert by friction the force thus obtained into its primitive form. For every degree of temperature generated in his axles a definite amount would be withdrawn from been invoked to prove that the observed differences of temperature between sea and air were due solely to mechanical action. Nevertheless, the tradition is an old one, as the following quotation proves: In one of those gales on September 12, Dr. Irving tried the temperature of the sea in that state of agitation, and found it considerably warmer than that of the atmosphere. This observation is the more interesting, as it agrees with a passage in Plutarch's Natbil-ural Questions-not, I believe, before taken notice of or confirmed by experiment-in which he remarks that the sea becomes warmer by being agitated in waves.”—A Voyage to the North Pole, undertaken by His Majesty's Commands 1773, by Constantine John Phipps. There are friends before me who have stood amid the foam of Niagara, and I have done so myself. Had we dipped sufficiently sensitive thermometers into the water at the top and at the bottom of the cataract, we should have found the latter warmer than the former. The sailor's tradition, also, is theoretically correct: the sea is rendered warmer by a storm, the mechanical dash of its lows being ultimately converted into heat. * I say "theoretically correct," because it would require far more care and instrumental delicacy than appear to have his urging force. There would be no absolute loss. Could he gather up all the heat generated by the friction and apply it mechanically, he would by it be able to impart to the train the precise amount of speed which it had lost by the friction. Every one of those railway porters whom you see moving about with his can of yellow grease and opening the little boxes which surround the carriage-axles is, without knowing it, illustrating a principle which forms the very solder of Nature. In the long run, however, the generation of heat cannot be avoided. All the force of our locomotives eventually takes this form. To maintain the proper speed, the friction of the train must be continually overcome, and the force spent in overcoming it is entirely converted into heat. An eminent writer has compared the process to one of distillation: the heat of the furnace distils into the mechanical motion of the train, and this motion recondenses as heat in the wheels, axles and rails. So also with regard to the greasing of a saw by a carpenter. He applies his force with the express object of cutting through the wood. He wishes to overcome mechanical cohesion by the teeth of his saw, and when it moves stiffly the same amount of effort may produce a much smaller effect than when the implement moves without friction. But in what sense smaller? Not absolutely so, but smaller as regards the act of sawing. The force not expended in sawing is misapplied, not lost; it is converted into heat. Here, again, if we could collect the heat engendered by the friction and apply it to the urging of the saw, we should make good the precise amount of work which the carpenter, by neglecting the lubrication of his implement, had simply converted into another form of power. We warm our hands by rubbing, and in cases of frost-bite we thus restore animation to the injured parts. By friction a lucifer match is raised to the temperature of ignition. In the common flint and steel the particles of the metal struck off are so much heated by the collision that they take fire and burn in the air. But the heat precedes the combustion. Hooke proved this, and Davy found that when a gunlock with a flint was discharged in vacuo no sparks were produced, but the particles of steel struck off, when examined under the microscope, showed signs of fusion. Before the safety-lamp was invented the workers in our coal-mines derived their light from showers of sparks generated by the friction of flint against the edge of a swiftly rotating steel wheel, the sparks having been considered incompetent to ignite the "firedamp." Aristotle refers to the heating of arrows by the friction of the air, and the most probable theory of shooting-stars is that they are small planetary bodies revolving round the sun, which, being caused to swerve from their orbits by the attraction. of the earth, are raised to incandescence by friction against our atmosphere. Chladni propounded this view, and Dr. Joule has confirmed it by calculation. He may, moreover, be correct in believing that the earth is spared bombardment through the breaking up of our aerolites by heat. These bodies move at planetary rates. The orbital velocities of the four interior planets are as follows: |