Fa. In order with certainty to produce these effects, it is necessary to study proportions very exactly, and to lay down an accurate scale by mathematical lines and figures after which to build the ship. Much has been written upon this subject, and nice calculations have been made of the resistance a ship meets with in making way through the water, and the best means of overcoming it; also, of the action of the wind on the sails, and their action in pushing on the ship by means of the masts. All these must be understood by a perfect master of ship-building.

Ch. But I think I know ship-builders who have never had an education to fit them for understanding these things.

Fa. Very likely; but they have followed by rote the rules laid down by others; and as they work merely by imitation, they cannot alter or improve as occasion may require. Then, though common merchant ships are trusted to such builders, yet in constructing men of war and Indiamen, persons of science are always employed. The French, however, attend to this matter more than we do, and in consequence, their ships generally sail better than ours.

Ch. But need a captain of a ship know all these things?

Fa. It may not be absolutely necessary; yet occasions may frequently arise in which it would be of great advantage for him to be able to judge and give directions in these matters, But suppose the ship built-what comes next?

Ch. I think she must be rigged.

Fa. Well-who are employed for this purpose?

Ch. Mast-makers, rope-makers, sail-makers, and I know not how many other people.

Fa. These are all mechanical trades; and though in carrying them on much ingenuity has been applied in the inven tion of machines and tools, yet we will not stop to consider them. Suppose her, then, rigged-what next?

Ch. She must take in her guns and powder.

Fa. Stop there, and reflect how many arts you have now set to work. Gunpowder is one of the greatest inventions of modern times, and what has given such a superiority to civilised nations over the barbarous. An English frigate, surrounded by the canoes of all the savages in the world, would easily beat them off by means of her guns; and if Cæsar were to come again to England with his fleet, a battery of cannon would sink all his ships, and set his legions a swimming in the sea. But the making of gunpowder, and

the casting of cannon, are arts that require an exact knowledge of the science of chemistry.

Ch. What is that?

Fa. It comprehends the knowledge of all the properties of metals and minerals, salts, sulphur, oils, and gums, and of the action of fire and water and air upon all substances, and the effects of mixing different things together. Gunpowder is a mixture of three things only, saltpetre or nitre, sulphur or brimstone, and charcoal. But who could have thought such a wonderful effect would have been produced by it?

Ch. Was it not first discovered by accident?

Fa. Yes-but it was by one who was making chemical experiments, and many more experiments have been employed to bring it to perfection.

Ch. But need a captain know how to make gunpowder and cannon?

Fa. It is not necessary, though it may often be useful to him. However, it is quite necessary that he should know how to employ them. Now the sciences of gunnery and fortification depend entirely upon mathematical principles; for by these are calculated the direction of a ball through the air, the distance it would reach to, and the force with which it will strike anything. All engineers, therefore, must be good mathematicians.

Ch. But I think I have heard of gunners being little better than the common men.

Fa. True-there is a way of doing that business, as well as many others, by mere practice; and an uneducated man may acquire skill in pointing a cannon, as well as in shooting with a common gun. But this is only in ordinary cases, and an abler head is required to direct. Well-now suppose your ship completely fitted out for sea, and the wind blowing fair; how will you navigate her?

Ch. I would spread the sails and steer by the rudder. Fa. Very well-but how would you find your way to the port you were bound for?

Ch. That I cannot tell.

Fa. Nor, perhaps, can I make you exactly comprehend it; but I can shew you enough to convince you that it is an affair that requires much knowledge, and early study. In former times, when a vessel left the sight of land, it was steered by observation of the sun by day, and the moon and stars by night. The sun, you know, rises in the east, and sets in the

west; and at noon, in these parts of the world, it is exactly
south of us. These points, therefore, may be found out
when the sun shines. The moon and stars vary; however,
their place in the sky may be known by exact observation.
Then, there is one star that always points to the north pole,
and is therefore called the pole-star. This was of great use
in navigation, and the word pole-star is often used by the
poets to signify a sure guide. Do you recollect the descrip-
tion in Homer's "Odyssey," when Ulysses sails away by him-
self from the island of Calypso-how he steers by the stars?
Ch. I think I remember the lines in Pope's translation.
Fa. Repeat them, then.

Ch. Placed at the helm he sat and marked the skies,
Nor closed in sleep his ever-watchful eyes,

There view'd the Pleiads, and the northern team,
And great Orion's more refulgent beam,

To which around the axle of the sky,

The Bear revolving, points his golden eye;
Who shines exalted on the ethereal plain,
Nor bathes his blazing forehead in the main.

Fa. Very well-they are fine lines indeed! You see, then, how long ago sailors thought it necessary to study astronomy. But as it frequently happens, especially in stormy weather, that the stars are not to be seen, this method was subject to great uncertainty, which rendered it dangerous to undertake distant voyages. At length, near five hundred years since, a property was discovered in a mineral, called the magnet or loadstone, which removed the difficulty. This was, its polar ity, or quality of always pointing to the poles of the earththat is, due north and south. This it can communicate to any piece of iron, so that a needle well rubbed in a particular manner by a loadstone, and then balanced upon its centre so as to turn round freely, will always point to the north. With an instrument called a mariner's compass, made of one of these needles, and a card marked with all the points, north, south, east, west, and the divisions between these, a ship may be steered to any part of the globe.

Ch. It is a very easy matter, then.

Fa. Not quite so easy, neither. In a long voyage, cross or contrary winds blow a ship out of her direct course, so that without nice calculations both of the straight track she has gone, and all the deviations from it, the sailors would not know where they were, nor to what point to steer. It is also frequently necessary to take observations, as they call it;

that is, to observe with an instrument where the sun's place in the sky is at noon, by which they can determine the latitude they are in. Other observations are necessary to determine their longitude. What these mean, I can shew you upon the globe. It is enough now to say that, by means of both together, they can tell the exact spot they are on at any time; and then, by consulting their map, and setting their compass, they can steer right to the place they want. But all this requires a very exact knowledge of astronomy, the use of the globes, mathematics, and arithmetic, which you may suppose is not to be acquired without much study. A great number of curious instruments have been invented to assist in these operations; so that there is scarcely any matter in which so much art and science have been employed as in navigation; and none but a very learned and civilised nation can excel in it.

Ch. But how is Tom Hardy to do? for I am pretty sure he does not understand any of these things.

Fa. He must learn them, if he means to come to anything in his profession. He may, indeed, head a pressgang, or command a boat's crew, without them; but he will never be fit to take charge of a man-of-war, or even a merchant ship.

Ch. However, he need not learn Latin and Greek.

Fa. I cannot say, indeed, that a sailor has occasion for those languages; but a knowledge of Latin makes it much easier to acquire all modern languages; and I hope you do not think them unnecessary to him.

Ch. I did not know they were of much importance.

Fa. No! Do you think that one who may probably visit most countries in Europe, and their foreign settlements, should be able to converse in no other language than his own? If the knowledge of languages is not useful to him, I know not to whom it is so. He can hardly do at all without knowing some; and the more, the better.

Ch. Poor Tom! then I doubt he has not chosen so well as he thinks.

Fa. I doubt so, too.

Here ended the conversation. They soon after reached home, and Charles did not forget to desire his father to shew him on the globe what longitude and latitude meant.

THINGS BY THEIR RIGHT NAMES.

Charles. PAPA, you grow very lazy. Last winter you used to tell us stories, and now you never tell us any; and we are all got round the fire quite ready to hear you. Pray, dear papa, let us have a very pretty one.

Father. With all my heart-What shall it be?

C. A bloody murder, papa!

F. A bloody murder! Well, then-Once upon a time, some men, dressed all alike—

C. With black crapes over their faces.

F. No; they had steel caps on:-having crossed a dark heath, wound cautiously along the skirts of a deep forestC. They were ill-looking fellows, I daresay.

F. I cannot say so; on the contrary, they were tall personable men as most one shall see :-leaving on their right hand an old ruined tower on the hill

C. At midnight, just as the clock struck twelve; was it not, papa?

F. No, really; it was on a fine balmy summer's morning; --they moved forwards, one behind another

C. As still as death, creeping along under the hedges.

F. On the contrary-they walked remarkably upright; and so far from endeavouring to be hushed and still, they made a loud noise as they came along, with several sorts of instruments.

C. But, papa, they would be found out immediately.

F. They did not seem to wish to conceal themselves: on the contrary, they gloried in what they were about.-They moved forwards, I say, to a large plain, where stood a neat pretty village, which they set on fire

C. Set a village on fire, wicked wretches!

F. And while it was burning, they murdered-twenty thousand men.

C. O fie! papa! You don't intend I should believe this; I thought all along you were making up a tale; as you often do; but you shall not catch me this time. What! they lay still, I suppose, and let these fellows cut their throats!

F. No, truly, they resisted as long as they could.

C. How should these men kill twenty thousand people, pray?
F. Why not? the murderers were thirty thousand.
C. O, now I have found you out! you mean a BATTLE.
F. Indeed I do. I do not know any murders half so bloody.