moderating. With a seaman's glance at the lighthouse pier the time to set about it may be determined, and in all cases this will be when Point Levis of the fort shows itself; and this is most important to observe, so as to avoid getting upon it and being wrecked.

This port has an imposing appearance, but there is no water for large ships, as we have said above. It is well sheltered, but requires the utmost promptness in manoeuvring, especially in taking off sail, and when there are many vessels lying there the last arrived will only have small shelter. But this is a condition which must be risked, and for this, if sail is taken off outside from the fear of some accident, the vessel will run the risk of being lost.

It may also occur that the wind hauls to the N.E., so that, being well to the eastward, a vessel may find herself with the entrance hidden. Care must be taken to provide against this very dangerous case. To avoid it, all the fore and aft sails must be set, and, in fact, as much sail as possible, in spite of the wind; and when on the point of entering the low sails should be taken in. Then, if the vessel finds herself screened suddenly on making the entrance, the topgallant sails may be taken in and the topsails set quickly. The way of the ship and the fore and aft sails should take her into the port.

In this port, excepting on the starboard shore on entering and the lighthouse pier as far as the foot of the town, the bottom is composed everywhere of soft mud.

(To be continued.)

THE GALE.

At this period of the year, when heavy storms are of frequent occurrence, the following article on "The Gale," taken from the last number of the Journal of the National Life-Boat Institution, will be perused with interest.

We are not about to write a sermon, although we have commenced with a text; but the sentiment conveyed by it is so beautiful and appropriate to our subject that we cannot resist its introduction. And surely it may be both advantageous and interesting to many of our seafaring readers to study reverentially, and somewhat more attentively than they may have already done, that mysterious phenomenon, the mighty gale, which, though they see it not, they both sensitively hear and keenly feel; whose effects, so far as evident to them, may have seemed to be only or chiefly evil; and on which, in moments of anxiety or self-reproach, some of them may even have looked with fear and trembling, as an agent of Divine wrath, strewing its pathway with devastation and woe.

Now, we hope to make it clear to such persons that the fiercest gale,

"The wind bloweth where it listeth, and thou hearest the sound thereof, but canst not tell whence it cometh, and whither it goeth."

however calamitous in some of its effects, is not an instrument of anger, or the result of a fortuitous chance; but that, on the contrary, it is a part of a well considered and benevolent plan, chiefly an instrument of good, and that its partially destructive effects are only sufficient to place it in the category of imperfection, in which all things in this temporary world must be classified. And surely they may derive from such knowledge that calm and resolute acquiescence in God's providence as shall come to their aid when danger threatens, and impart to them the coolness of head and strength of nerve which shall best enable them to successfully battle with and avert its consequences. If in any cases such should be the result, we shall have attained the practical end which we have in view. For how many valuable ships, and still more valuable human lives, annually perish from the want of that cool judgment and presence of mind in those in command, which, in moments of extreme peril, is beyond price!

It is, of course, known to every one that the wind is merely the air in motion: but the nature of the air, the reason why it is put in motion, and what occasions its being so, is known to comparatively few. We will briefly attempt to supply that rudimentary knowledge of the subject which should be possessed by every one, and which cannot but be both interesting and useful.

The air, which is the first essential to all animal and vegetable life, is what is termed an elastic fluid: although invisible to us, it is as much a fluid as water and the many other ordinary liquid bodies which are visible to the eye, and with which every person is familiar; but it is much lighter than liquids, or, technically speaking, it has less density. It also possesses the property of elasticity to an indefinite extent, which water and other liquid bodies do not. Thus water, even under enormous pressure, can only be slightly compressed into a smaller compass; but air can be compressed by force, or expanded by the withdrawal of pressure, to an amazing extent. For instance, a thousand cubic feet of air, by the aid of sufficiently powerful machinery, might be compressed into the space of one cubic inch, whilst, on the other hand, if from an air-tight vessel, of sufficient strength, holding a thousand cubic feet of air, the whole of it except one cubic inch could be artificially abstracted, the remaining cubic inch would, from its own elasticity or expansive power, completely fill the whole vessel.

The air which surrounds this globe is a compound body,-that is to say, it is composed of different bodies, which can be separated one from the other. Its principal ingredients are two gases, called oxygen and nitrogen; these are mechanically combined in the proportion of four measures of nitrogen to one measure of oxygen. In the great laboratory of nature they are being constantly separated the one from the other, by the respiration or breathing of animals and of plants, and by combustion or burning, and also by the oxidation of metals, fermentation, &c.

This important body, the air, without which no animal or vegetable life could for a moment exist, and on the purity of which the healthy

state of each so greatly depends, has been generally supposed to be of essentially a local character, being confined to a comparatively short distance ahove the earth's surface, and which distance has been vari`ously computed by astronomers at about forty or forty-five miles. Such, however, is the elasticity of the air, that at the height of about three and a half miles above the sea level, the aeronaut or mountain traveller has ascended through one half of the atmosphere; the remaining half being less subject to pressure and the attraction of gravitation, occupying no less than forty or more miles in vertical height. At the level of the sea the barometer stands at the mean height of 30 inches; but at the height of 3-4 miles it stands at only 15 inches, at 6.8 miles at 7.50 inches.

Some idea of the attenuation of the air at a short distance above the earth's surface has been lately exemplified by Messrs. Glaisher and Coxwell, in their perilous balloon ascents in this country, when, on one occasion, at a few thousand feet above the earth's surface, the pigeons they threw out, beating the "thin air" with their powerful wings, obtained no support therefrom, but fell rapidly, as though lifeless, towards the earth; and when at the extreme height of six and a half miles, to which they ascended, the combined effects of the reduced pressure on their bodies and the more rarefied food to their lungs reduced Mr. Glaisher to a state of insensibility, and almost overpowered Mr. Coxwell, thus proclaiming, as in so many words, to the race of man, "So far canst thou come, but no farther, and hither shall thy proud course be stayed."

We have stated that the air is a compound body, and that its component parts are readily separable the one from the other by various means. It is also capable of holding foreign bodies, such as aqueous and other vapours and exhalations, and minute particles of vegetable and mineral solids, in the shape of dust; and of retaining in connection with it other gases, the products of the decomposition of animal and vegetable matter, and of combustion. It follows, therefore, that its properties near the earth's surface, as a respiratory and alimentary medium, must be of a varying character, according as foreign bodies, by exhalation or otherwise, have mingled with it. It is, however, a remarkable proof of design that the two chief constituents of the atmosphere are always in the same proportion: for whether in a fever hospital or on the top of a mountain, the nitrogen and the oxygen are in the ratio of four to one.

But, even if experience did not prove such to be the case, we might reasonably expect, from the analogies of nature, that some one especial state and proportional combination of the ingredients of the air would be fitter for the respiration and health of animals and vegetation than any other, and that, therefore, some plan would have to be devised and arranged to maintain generally that happy equilibrium. We need not, however, theorise on this point: for the statistics of health and the returns of the registrars of deaths only too plainly record the often dreadful effects of poisoned air in our larger cities and towns, from want of ventilation in the dwellings of the poor, and from insufficient NO. 12.-VOL. XXXII,

4 Q

or imperfect sewerage in general; and in many of our rural districts, from the malaria arising from undrained marshes and swamps.

Before, however, seeking for that machinery in nature, devised to compensate for such local disturbances of the purity and life-supporting properties of the air we breathe and live on, it may be worth while to consider for a moment, some of the known important properties of the air, although all those properties which Infinite Wisdom has planned may not, and perhaps never will, be discovered by man. In describing, or rather briefly relating, some of these wondrous perties, we shall not attempt to enter into an explanation of them, this not being a scientific treatise, and our only object being to convey some faint impression, in this one phase of nature, to the minds of the more unscientific of our readers, of the wisdom, and power, and contrivance that have been, and are being, exerted by the Great Creator of all things for the sustenance and welfare of his creatures.

pro

1. Support of Animal and Vegetable Life.—The first and highest function of the air, if we may reverently use the expression, is the support of the life of man, of intelligent beings; the support of the life of all the inferior races of animals and of the vegetable world being subservient to it. It will be sufficient to state that this wonderful power is effected through the medium of organs which, in the higher classes of animals, reside in the lungs and in the skin, and in plants in their leaves, which organs have the power of decomposing the air, and appropriating that portion of it which is necessary for the growth or support of animal or plant, and discarding that part which would be useless or injurious to it. It will be sufficient to further state generally that that part of the air which is exhaled by the animal as a product of respiration is necessary to the plant, and that that part which is changed by the animal and by combustion is vivified, so to speak, by the expiratory organs of the vegetable world, and that thus the general equilibrium or purity of the atmosphere is maintained.

2. Combustion.-Without the medium of the air there could be no combustion, as the process is commonly understood, since fire cannot under ordinary circumstances exist unless fed by oxygen gas; and inflammable bodies, in giving out heat and light, decompose the air and consume its oxygen. Indeed, the process by which the air is decomposed and its oxygen appropriated by the breathing organs of animals, thereby producing animal heat, is a species of combustion. How great a necessity, therefore, is this property of the air must be felt by every one.

3. Evaporation.-Another important property of the air or atmosphere, caused by its density and weight, is the distribution of moisture. The minute aqueous particles which now float upwards through the air become partially condensed under change of temperature; they congregate in clouds, and are carried by the winds of heaven over the dry land, there to fall in refreshing rain, revivifying the face of nature, and replenishing the lakes and springs and rivers for the use of man. If there were no atmosphere, the ocean, to be sure, and the dry land would still exist: but the former would be calm, and still,