tion a to public speaker; and an apparent, though probably not the legitimate, proof of the effect having been produced by the sound of the voice of the speaker is derived from the fact, that upon his ceasing to speak, the sleeper usually awakes. There are few, again, who have not known from personal experience that certain tones affect the teeth with that peculiar and unpleasant sensation familiarly described under the term, set on edge. Even in the appalling sensation excited by thunder, the mind is probably overawed by the physical effect produced on the nervous system by the crash, rather than by any apprehension of danger from the thunder itself: for that sensation is usually excited even in those who are most assured that no danger is to be expected from the loudest crash of the thunder, but only from the lightning which accompanies it. Nor is it unreasonable to suppose that an analogy exists between the sense of hearing and the other senses, with reference to the objects of their several sensations: and since in the case of taste, of sight, of smell, and of touch, some objects are on reasonable grounds conjectured to be naturally offensive, while others are agreeable to the respective senses; why, it may be asked, should not the same relations hold with respect to the ear and the peculiar objects of its sensation? Evelyn well observes, that the bountiful Creator has left none of the senses which he has not gratified at once with their most agreeable and proper objects.

Of all the objects of sense, sound perhaps, as a principle of mental association, the most powerfully excites the recollection of past scenes and feelings. Shakspeare briefly elucidates this principle in these lines:

"Yet the first bringer of unwelcome news
Hath but a losing office; and his tongue
Sounds ever after as a sullen bell,

Remembered knolling a departed friend."

HENRY IV. Part II. Act I. Scene 1.

The author of the "Pleasure of Memory" not less forcibly illustrates the same principle.

"The intrepid Swiss, who guards a foreign shore,
Condemned to climb his mountain cliffs no more,
If chance he hear the song so sweetly wild,
Which on those cliffs his infant hours beguiled,
Melts at the long-lost scenes that round him rise,
And sinks a martyr to repentant sighs."

ROGERS, &c. page 21, line 1.

Nor is the principle less powerfully illustrated in that most beautiful Psalm beginning with the words, "By the waters of Babylon we sat down and wept:" for who can read that affecting apostrophe, "How shall we sing the Lord's song in a strange land," without entering into all the pathos of the scene represented by the sacred poet to the imagination?

It is said to be the opinion of the Hindoos, and though not of much value in argument, there is at least a metaphysical elegance in the opinion, that the remarkable effects of music on the human mind depend on its power of recalling to the memory the airs of paradise, heard in a state of pre-existence.

But, if an individual instance of the truth of the present position were to be selected, it would not be possible perhaps to find one more impressive than that which has been recorded of the late emperor of the French. It is said that at that period of his life, when the consequences of his infatuated conduct had fully developed themselves in unforeseen reverses, Napoleon, driven to the necessity of defending himself within his own kingdom with the shattered remnant of his army, had taken up a position at Brienne, the very spot where he had received the rudiments of his early education; when, unexpectedly, and while he was anxiously employed in a practical application of those military principles which first exercised the energies of his young mind in the college of Brienne, his attention was arrested by the sound of the church clock. The pomp of his imperial court, and even the glories of Marengo and of Austerlitz, faded for a moment from his regard, and almost from his recollection. Fixed for a while to the spot on which he stood, in motionless attention to the well known sound, he at length gave utterance to his feelings; and condemned the tenour of his whole subsequent life, by confessing that the hours, then brought back to his recollection, were happier than any he had experienced throughout the whole course of his tempestuous career. He might perhaps with truth have added, when looking at the various objects of the surrounding scenery,

"I feel the gales, that from ye blow,

A momentary bliss bestow."

Perhaps also during this moment, and in making a confession so humiliating, he actually did experience that moral state represented by Milton to have been felt by the fallen angel

"Thrice he essayed (to speak); and thrice, in spite of scorn,
"Tears, such as angels weep, burst forth—”

But the effect produced on his mind seems to have been momentary; at least it certainly did not alter his course of action. And too probably he was at that time rather tormented by remorse, than softened by repentance; a state but little favourable to the adoption of better counsels, even if he could then have retrieved his fortunes by such a change.

SECTION X.

Effects of the Motion of the Air, as connected with the Arts, &c.

I PROCEED now to consider the effects of the atmosphere, while in a state of motion, in aiding the various arts and operations of civilized

society; in which the action is sometimes explicable on mechanical, sometimes on chemical, or on physical, principles.

It would not be a short or easy task to enumerate the various substances which require to be deprived of all sensible moisture, in order to be applicable to the immediate purposes of life; nor in order to be capable of being preserved in a state fit for future use: and the separation of that moisture which they may contain in their natural state, or which they may have accidentally contracted, can in general only be effected by exposure to the open air: but as that portion of the air, which is in contact with the moistened substance, would soon be so far saturated with the vapour arising from it as to be incapable of absorbing more, it must necessarily be replaced by successive portions of fresh air; in order that the substance may be thoroughly dried and hence we see the advantage of currents of air, or, in common language, of the wind, for the purposes in question. Without the aid of such currents, the grass newly mown would often with difficulty be converted into hay: and with still more difficulty would that conversion take place should it during the process, as is most likely to happen, be exposed to rain. The same difficulty would occur, but attended with much more serious effects, in the case of sheaves of wheat or barley, which having been once drenched with rain would be rendered unfit for producing bread, unless the moisture were soon dissipated and with respect to the process of reducing the corn itself to the state of meal, that is, in common language, of grinding it; although many other mechanical means are capable of being applied to that purpose, who does not see the advantages of the common windmill, even where other means are available, which in many places they would not be? but windmills would themselves be unavailable, were there no currents of air to set them in motion.

In the drying of moistened linen, and of paper newly made; in the seasoning, as it is called, of wood; and on numerous other occasions, the same advantages occur from the same cause, and are explicable in the same way. But there is one instance, of very familiar occurrence, where the effect of a free ventilation is productive of the greatest comfort. At the breaking up of a long protracted frost, during which the air has been enabled to absorb and retain in an insensible state an unusual quantity of moisture, that moisture, as soon as the thaw takes place, is deposited upon the surface of every thing with which it comes in contact: and there can be scarcely an individual, from the peasant to the noble, who has not often experienced the comfortless state of the interior of his habitation from this cause. The opulent indeed, supposing that nature did not provide the remedy, might easily remove, and often do accelerate the removal of the evil, by the introduction of currents of air artificially heated: but the indigent, incapable of commanding so expensive a remedy, would meet with serious detriment, did not a timely change in the state of the atmosphere enable it to re-absorb the moisture which had pre

viously been discharged from it; for many parts of the furniture of their habitation would be injured, or even destroyed by the moisture imbibed by them: and with respect to a much more important point, a healthy state of body, both the opulent and the indigent would be alike sufferers, from a continued exposure to the external atmosphere in such a state.

In the foregoing instances currents of air have been considered as acting on a fixed point as it were, or on bodies nearly stationary. Let us now consider their action on bodies capable of being set in motion, as nautical vessels of all kinds, and we shall not fail to see the importance of that action to some of the highest interests of man.

To those, of whatever condition in life, who are surrounded by the numerous resources of a commercial city, it is immediately of little import, unless as a question of mere corporeal feeling, whether the air be in a state of perfect calm, or freshened by a breeze; and whether that breeze be from the east, or from the west. To the agriculturist even it is comparatively of little interest, unless at particular seasons, whether the wind be high or low, or from what quarter it may come; further than as particular states and directions of the wind are indications of rain or drought. But to those "who go down to the sea in ships, and occupy their business in great waters," not only the degree of force, but the direction of the wind, is of the highest moment: while on many occasions, even in the present advanced state of science and naval architecture, a motionless state of the atmosphere, or a calm, might be fatal to all their speculations. Every one who has lived for a time on the sea-coast must have observed with what anxiety the owner of the smallest fishing boat watches the variations in the state or direction of the wind, as connected with the practicability of putting out to sea. If the wind be in an unfavourable quarter, or if it blow not with sufficient force to swell his sails, he saunters in listless inactivity along the beach but if the wished for breeze spring up, the scene is at one changed, and all is alacrity and life.

In some parts of the world Providence has compensated for the disadvantages arising from the general uncertainty of the wind, by the continued regularity of its direction through stated seasons: in consequence of which, the merchantman calculates upon the commencement and duration of his voyage with a degree of security and confidence, which sets him comparatively at ease as to the event. These periodical currents of air indeed have been named from this very circumstance the trade winds: and, in illustration of their adaptation to the purposes of commerce, a more striking instance perhaps could not be adduced than the following, which is given in a volume, entitled, "Four Years Residence in the West Indies," written by a gentleman by the name of Bayley.* In the description of the island

* London, 8vo, 1830, p. 292.

of St. Vincent it is there stated that a little sloop, the private signal of which was unknown to any of the merchants, sailed into the harbour one morning, and immediately attracted the notice of the surrounding crowd; and the history of its unexpected appearance is thus given. "Every one has heard of the little fishing smacks employed in cruising along the coast of Scotland; which carry herrings and other fish to Leith, Edinburgh, or Glasgow, worked by three or four hardy sailors, and generally commanded by an individual having no other knowledge of navigation than that which enables him to keep his dead reckoning, and to take the sun with his quadrant at noonday.

"It appears that a man who owned and commanded one of these coasting vessels had been in the habit of seeing the West India ships load and unload in the several ports of Scotland; and, having learned that sugar was a very profitable cargo, he determined, by way of speculation, on making a trip to St. Vincent, and returning to the Scottish market with a few hogsheads of that commodity. The natives were perfectly astonished-they had never heard of such a feat before; and they deemed it quite impossible that a mere fishing smack, worked by only four men, and commanded by an ignorant master, should plough the boisterous billows of the Atlantic, and reach the West Indies in safety; yet so it was. The hardy Scotchman freighted his vessel; made sail; crossed the bay of Biscay in a gale; got into the trades; and scudded along before the wind, at the rate of seven knots an hour, trusting to his dead reckoning all the way. He spoke no vessel during the whole voyage, and never once saw land until the morning of the thirty-fifth day; when he descried St. Vincent's right a-head and setting his gaft-topsail, he ran down under a light breeze, along the windward coast of the island; and came to anchor about eleven o'clock under the circumstances before mentioned."

Such a vessel, and so manned, could hardly have performed the voyage here described, had it not been aided by the current of the trade wind: and what then must be the advantage of such a wind, when, instead of aiding the puny enterprise of a single and obscure individual, it forwards the annual fleets of mighty nations. Most important therefore to the Roman empire was the discovery of Hippalus, which enabled its fleets to stretch across at once from the African to the Indian coast by means of the south-westerly monsoons. But, if we would view the subject in all its magnitude, let us contemplate with a philosophic eye the haven of any one of the larger sea-ports of Europe; filled with vessels from every maritime nation of the world, freighted not only with everything which the natural wants of man demand, or which the state of society has rendered necessary to his comfort, but with all which the most refined luxury has been able to suggest. "Merchandise," to use the words of Scripture, "of gold, and silver, and precious stones, and