POWERS OF THE LORD.

O all ye Powers of the Lord, bless ye the Lord: praise Him, and magnify Him for ever.

HITHER can we go from Thy presence," or in what direction can we cast our eyes without perceiving that we are hedged in on every side by the Powers of the Lord? Above, below, around-in the air, in the water, on the earth and under the earth they pervade creation. At every turn they reveal themselves in the mighty language of physical, chymical and vital force, bringing home to our minds at every instant our dependence upon Him, and leading us on to thankful adoration.

The verses of the Benedicite may be considered as a summary of these Powers, and many of them, therefore, will be found noticed elsewhere in this book. In this place we shall confine our attention

to a few of the more striking illustrations drawn from the familiar objects around us.

The Powers of the Lord shine forth in the Heavens—in sun, moon and stars—with a grandeur which we cannot fully comprehend, but which nevertheless elevates our nature in the mere effort to grasp it. In every meditation on those Powers we find ourselves instinctively turning again and again towards the sun, the great messenger of the Lord, which brings to our earth so much of the force and movement we see continually displayed upon it. Under Providence, the sun stands forth as the pivot of the solar system, sustaining and preserving by the power of gravity the planets that circle round it. On earth the operation of the same power is no less necessary and universal. By solar gravity all things are attracted towards the centre of the sun, while by terrestrial gravity everything belonging to our globe is drawn towards the centre of the earth. Terrestrial gravity, therefore, counteracts the centrifugal tendency of objects, resulting from the earth's rotation, and keeps them fixed upon the surface with a force of which the amount is termed their weight. Let us reflect how It holds everything

universally useful this power is. in its place. It keeps one stone pressed down upon another, and thus makes building practicable. Bodies that have little gravity, or that are light,

possess little stability and are readily tossed hither and thither. Our bones and muscles, and the strength of plants and all other materials are adjusted to the strain which gravity makes upon them. In obedience to its laws the ship floats upon the water, and the balloon soars into the air. It is gravity which enables us to balance ourselves in walking, running or riding. By the adjustment of their gravity to the medium in which they are placed birds fly and fishes swim. In short there is no limit to the conveniences and benefits we derive from this "Power of the Lord."

Another Power essential to our well-being is Friction, which, in conjunction with gravity, regulates physical motion. It is the force which opposes displacement, which keeps things steady, and finally brings them, if in motion, to a state of rest. With every kind of movement some frictional opposition will always be found at work tending to stop its continuance. It may be the rough surface of the ground, or the comparatively unresisting water, or the still softer air, but each with varying degrees of frictional energy ultimately subdues the moving force, and sets the body at rest. Many are the attempts ingenious man has made to overcome this difficulty, but his search after "perpetual motion" is ever baffled by omnipresent friction, and his greatest success is measured only by the

gain implied in substituting a friction that is less for one that was more. Thus we oil axles and hinges, to diminish the rubbing opposition. Thus wheels were invented to escape in some degree from friction by rolling over the rough ground instead of scraping over it. Thus, also, by gradual improvement rude tracks were changed into smooth, macadamised roads, and these last in their turn are yielding to the even rail. Every new success has been merely the lessening of friction.

In these and in many other ways friction may be said only to create difficulties which man's ingenuity enables him to overcome with more or less success; but, as a set off against these evils, let us for a moment try to realise what would have happened if there had been no such Power in existence. When a surface offers little friction we call it slippery; and ice, though offering resistance sufficient to bring a skater or a stone gradually to rest, is yet remarkable for the comparative absence of friction. What occurs? In venturing upon it most persons find their movements difficult even when the surface is level, but they find it impossible to stand when ice is upon the slope. Now if there were no such thing as friction, land would be no longer terra firma, but would be as slippery as ice. Without mechanical support it would have been impossible to ascend a hill. Horses could not

have kept their feet against a strain; everything we handled would have slipped through our fingers with eel-like glibness. Quiescence and steadiness would have been banished from the world, and objects once set in motion would have gone on without stopping until brought up by some equal opposing force. Thus it may be perceived that the friction of matter assists us in almost every act we perform; and, without its aid, the innumerable purposed movements of every day life would have been impossible in the general confusion of the world. "Without this property," says Dr Whewell, "apartments, if they kept their shape, would exhibit to us articles of furniture and of all other kinds sliding and creeping from side to side at every push and at every wind, like loose objects in a ship's cabin, when she is changing her course in a gale."

Seeing that the frictional power of the atmosphere is sufficient to bring all things exposed to it to rest, some may be inclined to ask why the heavenly bodies do not gradually move more slowly and ultimately stop? Long continued observation proves either that the orbital course of the heavenly bodies lies in a vacuum where friction does not exist, or that it takes place in a medium so attenuated that the frictional resistance practically amounts to nothing. All astronomers agree