modest agencies of our atmosphere could do, if by any chance the force which drove them about were permitted to be for any length of time animated by a mad and frantic spirit of destruction. We are told now on all hands that invisible agencies of great physical capacity can be exerted through persons called "mediums," agencies quite equal to driving heavy furniture about rooms, and sending ponderous gentlemen and musical boxes sailing away under the ceiling. Well, suppose a band' of these remakable agencies, which seem to take so much delight in what is called "materialization," should get hold of the atmosphere for a few weeks at a time, and make it perform the mad tricks which tables and chairs are asserted to perform by the "Spiritualists." Macbeth's witches evidently had some such notion in their heads, and boasted that the object of their spite should be tempest-tossed, though his ship could not be utterly destroyed. And it does seem as if it might be easier for spirits to raise the wind, and let the wind thus raised float the heavy objects which they now exert themselves so much to drive about the rooms in which seances are held, than to make these great mechanical efforts directly, themselves. At a superficial guess, at all events, pneumatic exercitations would seem to be more in a spirit's way than the habit of discharging heavy projectiles. They always used to be called the "powers of the air," and there can be no doubt but that, if they want to do mischief, the air is a very wide sphere of influence for them.
So far from its being a marvel that we now and then have these tremendous disturbances in the atmosphere, the marvel ought to be that, considering the perfect fluidity of the transparent and invisible medium which is wrapped round the earth, its great mobility under even slight changes of temperature, and the awful force with which now and again it does sweep over us, we so seldom hear of the sort of confusion which appeared to reign everywhere between Sunday and Wednesday. Why should it be so seldom heard of that every yard within a walk of two miles should be strewn with tiles, chimneypots, brickbats, or some other vestige of the propelling power of the wind, as happened on Sunday, for instance, at Boulogne? Why should not the whole area of our island be oftener in the condition of that appositely named Estaminet des Vents which the hurricane suddenly turned inside out on Sunday in the same town? We suppose that the real guarantee I against constant repetitions of such scenes of destruction is the enormous elasticity of the particles of the atmosphere,—which causes them to spring asunder in so many directions, on the slightest of impulses, that it is far more difficult to hold the force exerted to pusFfing in a single direction than it is in the case of either liquids or solids. These terribly destructive storms are only possible, we suppose, when the forces which act upon the air are so combined as to condense a considerable volume of air and drive it steadily in a given direction, just as the compressed air which causes the explosion of an air-gun is kept by the barrel in which it is enclosed from expanding in any direction but one. Now, of course, this seldom happens in the case of an atmosphere which is only tied by the force of gravity to our planet. It is very rare, we suppose, under such conditions, for the constraint to be so exerted as to overcome the elastic tendency of the particles of air to spring apart, whereby they lose the continuity and coherence requisite for a combined attack on the rickettiness of human structures. It is the high volatility of the air which is our best security against the fixity needful for frequent discharges of such artillery as those of the early part of this week. A force which, if exerted to drive a stone or a bullet, would kill at once, and which, even if it were employed to drive water, would prove a most formidable power, is almost thrown away in the air, whose particles reflect it so instantaneously in all sorts of directions, that only a rapidly diminishing driving power is usually transmitted in the direction of the force impressed. Air is too much adapted for dancing away towards all quarters of the compass to be well fitted, without artificial manipulation, for the purposes of a battering-ram or a Bramah press. Indeed, it is in the gullies and narrow valleys, where something of this artificial constraint is provided for the air-currents, that, when such currents do happen to sweep through them, they are most terrible in the ruin which they bring.
It is, of course, chiefly the physical mischief caused by these tempests which arrests the attention of men. When there is a cloud of hats and chignons in the air, people do not think very much of the state of their brains or nerves, and yet the changes in the pressure of the atmosphere probably do cause more discomfort to most of us through our brains, than they cause even through the rape of our hats,
