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me.

the garden of the Lord, but this I O God! Thou art my God, the know : it will be the right path. God of my mercy, Who goeth before

Look at the children of Israel The old sins that once held me as they move on through the wilder- in bondage may still pursue, but Dess : the Lord going before them, Thou art my Refuge and Strength. by day in the pillar of cloud, and New temptations may wait for my in the pillar of fire by night. That coming, but if my God goeth before is enough, let them follow on. The me, He will have grace waiting for mountain rocks shut them in, or me and strength according to my the pathless desert stretches all around need. Ever quicker than the arrow of them. What of that? God goes our foe is the shield of our Defender. before them. Be quite sure that the • Simon, Simon, behold, Satan hath God of our mercy will not be less to desired to have you '--yonder he us than He was to them. The twi- waits, lurking in the way,—that he light of Gospel type was not brighter may sift you as wheat : but I have than the noon of Gospel day. Take prayed for thee, that thy faith fail this simply, fully, to the letter, and not. Forth against my foes, the God rest in it : The God of my mercy shall of

my mercy goeth before me. go before me. There is no path of The God of my mercy goeth beyour life, at home, in business, in fore me : then He will know my tenothe Church, but if you will look poral wants. Look at Israel again. trustfully, you shall see God going Here they come—so many hundred before you. There is no perplexity, thousand, besides the children. And no event, however passing or trivial, about them a desert ! Surely they but if you will only look, you shall are brought up here to die. The find God leading you aright. We fierce sun will beat upon them by guess at our way and choose what day ; wild beasts and robber bands we think best : so do we grieve will come to prey upon them by night. the God of our mercy, and get our- And what can they eat ? Here is no selves into trouble. Set it up in bread; corn won't grow in this sandy letters of gold: The God of my mercy waste and on these barren rocks. goeth before me. And let our work But the God of their mercy goeth be neither choosing nor guessing, but before them. Here by day the pillar following trustfully where he shall of cloud throws upon them all its lead.

kindly shade : the sun can not smite The God of my mercy goes

before them; and when darkness comes, the me : then He will know my need. Fire-cloud burns with ruddy glow, Poor Israel! What chance is there their comfort and their safety : they for thee? Yonder is the furious need not fear the terror by night. Pharaoh with all his host. Here the At dawn of day the manna waits for Red Sea defies thee to advance. them, fresh, sweet, delicious ; and Better thou hadst tarried in Egypt! they gather from the desert, bread Lo, the God of their mercy goeth be- enough and to spare.' And what fore then, and down, as in the hollow though my path leads through the of His hand, there march theransomed wilderness ? the God of my mercy, He people along a way of triumph, smooth goeth before me, and' He will with the golden sand, and decked provide.' with dainty shell and sea-weed. A little lad, during the American What are the hosts of the enemy to war, was his widowed mother's comHim? He did blow with His wind, fort and joy. One day, as the poor and His sea covered them. They woman was trying to scrape the flour sank like lead in the mighty waters. from the sides and bottom of the

F

cheer

come.

barrel, to help out the day's supply, of little faith, wherefore dost thou
the lad cried, 'Mother, we shall have doubt?'
some more very soon now, I know.' Then up leaps a little flame from
Why do you say so, my boy?' asked the fire. "Cheer up,' it says,
the mother. Why, because you've up. Thousands of years ago, your
got to scraping the barrel. I believe Father saw that you would need my
God always hears you scraping the little bit of warmth this morning, and
barrel, and that's a sign to Him that need to be comforted with my ruddy
you want another.' And before the blaze. And He stored me up for
day was over the fresh supply had your use,-made me ready and kept

We
may

have come to the me waiting until now; and here I bottom of the barrel.

Then look up

am at last : His gift, to make you glad for more. Brother, have a tremendous with my heat, and to cheer you with faith' in the providence—the provid- my dancing flame.' ing-of our God.

One of the earliest Arctic explorers That was a sweet voice from the -the discoverer of Iceland—is said to empty barrel ; but not sweeter than have carried with him a number of a score of voices all about us if we ravens; and when he wanted to know had but ears and hearts to hear them. where the land lay, he would loose There you sit, mournful and despond- one of the birds, and then follow ing, wondering what you will do if the direction of its flight. A right this should happen or that. Listen, good use for our croaking cares : let for the crust on the table is preach- them fly away to the Lord ; and let ing a sermon. 'Look at me,' it says; us follow them, until we rest in Him. do you know where I come from? So let us go forth with a song

of Why, hundreds and thousands of years triumph, exulting in our God. ago, your Heavenly Father provided for your supply this morning. He

Awake, our souls ! away, our fears ! put the corn in man's hands : year

Let every trembling thought be gone!

Awake, and run the heavenly race, after year, for

six thousand years, He And put a cheerful courage on. has given the sunshine and shower to pass me on for you to-day; and

O mighty God! Thy matchless Power

Is ever new, and ever young ; here at last I am come from His hand

And firm endures, while endless years to feed and strengthen you. O thou Their everlasting circles run.'

6

NOTES ON CURRENT SCIENCE :

BY THE REV. W. H, DALLINGER, F.R.M.S. THERE is one problem which has of the problem, and a perception of exercised the most powerful and its nature, more accurate ; but, as penetrative minds alike of ancient and with the circulating decimal, or the modern times, and is to-day giving problem of 'squaring the circle,' every rise to as much thought and enquiry further step in the process brings us as any other subject that can engage nearer, and yet leaves us infinitely themind of man; but, nevertheless, its distant from the end. absolute solution may never be hoped The progress of enquiry into the for—it is the ultimate constitution of ultimate constitution of matter, none matter. All physical investigation, the less, is a most important chapter earnestly prosecuted, is leading up in the history of the work done by to it; and making & real statement mar in the past few decades. The

sure.

spectroscope has been a powerful and as Professor Wurtz should endeavour almost unparalleled instrument of to gather up and make plain the analysis, and aided by the higher advance made since Faraday's day in mathematics, has brought us into our knowledge of the constitution of new and wholly unexpected relations matter in the gaseous state. He to the great problem. It has enabled pointed out that the word 'gas' was us to demonstrate the uniformity of introduced by Helmont at the beginsubstance constituting the entire ning of the seventeenth century. He physical universe, and in our labora- further distinguished between gases tories to discern, with irresistible cer- and vapours. He regarded gases as tainty, the nature and conditions of being aëriform fluids incapable of the materials composing the most dis- reduction to the liquid state by cooltant bodies in the most outlying ing; but vapours were considered as abysses of the cosmos.

And more

gaseous under the influence of heat. than this, it gives us some power

of But this distinction does not now hold; penetration into the real nature-or for the gaseity or liquidity of any body rather, the ultimate condition of the is merely a question of the degree of substance from which the phenomena heat or cold, and pressure to which investigated proceed.

it is exposed. To find the constituents of a star, In 1823, Faraday succeeded in however distant, has become a com- making gaseous chlorine fluid. He monplace event, known by the school- did this under the influence of presboy, to be accomplished by the Phy- At the very same time, Sir sicists of our times; but by the same Humphry Davy described the liqueprocesses the cultivated, scientificmind faction of hydrochloric acid gas; and has been enabled to look deeper, and Faraday pursued these methods get glimpses of the actual condition amongst the more dense gases, such as of that which manifests the varied sulphurous acid, ammonia, sulphuphenomena studied. Thus recently reted hydrogen, carbonic acid, etc. Mr. Lockyer has found that there is Pressure, and not reduction of temcarbon in the sun-a discovery fol- perature, was the method he employed lowing quickly upon that of Dr. to prove that what appeared a permaDraper, proving the presence of nent gas could be changed into a oxygen in the same body. But Mr. liquid. During these experiments he Lockyer has further announced—and discovered in compressed coal gas, the announcement has been referred butylene-a compound of great imto in the recent address of the Presi- portance to the philosophicalchemistdent of the Royal Society,—that he and benzine, the importance of which has discovered indications that what is manifest enough in our own day. are considered 'elementary' bodies-- It is quite clear that, whether we as, for example, the metals—are com- reduce gases by pressure or by pound bodies : a suspicion long held diminution of temperature, the result by Physicists and Chemists; and that is to bring their ultimate atoms there is more than a probability that all

closer together.

But it is now the forms in which matter manifests known that mere pressure is not itself will be seen to arise in a few enough. Oxygen, hydrogen and nielements or perhaps even in one trogen have been compressed to an "element.

extent equal to a pressure of three It is not surprising therefore that, on thousand atmospheres, and their lique80 important an occasion as the de- faction has not been effected. They livery of the Faraday Lecture before were consequently considered 'permathe Chemical Sociaty, so greata chemist nent'gases. Butit has now been proved

and as

that if reduction of temperature be which, if unopposed, would launch the added to pressure, every gas known molecules into space. Clearly, then, in nature can be liquefied, or even

we must lower the 'kinetic energy made solid. But this fact has aided of a gas and increase its cohesion, us in coming to a true conclusion as until the moment arrives when the to the ultimate constitution of gases. cohesive force asserts itself, and the Bernduilli first enunciated the idea liquid condition will be secured. that gases are formed of incon- This explains why certain of the ceivably minute material particles, gases were for so long considered free in space and animated by very permanent.' It was from the enorrapid rectilinear movements, and mous degree of pressure, combined that the tension of elastic fluids with the extreme reduction of results from the shock of their temperature, required to give the particles against the sides of the molecules of such gases power to containing vessels. And this, which exercise their cohesive influence on is known as the kinetic theory of each other. And it was by devising gases, has been recently developed means for jointly securing these by Clausius and Clerk Maxwell. conditions that MM. Cailletet and

If, then, a gas occupying a certain Pictet have liquefied the permanent volume, composed of a

definite gases ;

and the latter has even number of particles, be in a closed solidified hydrogen ;

the vessel like the cylinder of an air- solid particles fell upon the floor pump, the pressure which it will they gave out that metallic ring exert upon the piston will be deter- which, amongst other things, confirmed mined by the number of shocks of the far-seeing idea of Faraday, that the molecules diffused through the Hydrogen is a metal. The result of neighbouring stratum of gas. If, this is, that from a physical point of therefore, the volume of the gas be view, gases and vapours have the reduced, the number of particles in same constitution : being formed of this layer will be increased, as well molecules which move freely in space. as the sum of the shocks; and in Thus it is in the gaseous state that proportion the pressure will be that matter becomes more accessible augmented The velocity with to our knowledge ; but full of wonwhich these ultimate molecules move derful fact and suggestion as all this is enormous. Clausius concludes that is, it must be distinguished, by the the molecules of air move with a mind loving accuracy and truth, mean velocity of four hundred and from actual demonstration. It eighty-five metres & second, and is an hypothesis after all, however those of hydrogen one thousand eight beautifully in harmony with the hundred and forty-four metres in experiments it seeks to explain. It the same time. But they cannot assumes that gases-indeed, that all all move at the same rate; for matter, consists of molecules, which they must constantly clash against in turn are bundles of atoms. But each other and rebound. But no one has ever seen molecule or by this freedom of movement atom, and we may fairly predict that they are very nearly emancipated no one ever will.

Yet the probability from cohesion. In liquids, the power that this explanation of the nature of cohesion is palpable, although it is of

gases is a correct one is very high ; such as to admit of the gliding of the and the phenomena of the Radiomolecules over each other. The meter only lend additional weight to molecular cohesion is constantly at the inference ; and it is not without strife with the force of expansion wonder that one contemplates the

mathematical side of this great pro- their fertilizing granules. The inblem, and finds that the human mind sect, satisfied, seeks to get out ; but has sought to determine, not only the the needle-like hairs, which from velocities of the gaseous molecules, their direction allowed it to enter, and the prodigious number of their absolutely prevent its exit : it is a collisions during a unit of time, but prisoner. But there is plenty of also their distances from each other, nectar, so that it has both barracks their absolute number in a given and rations. Meanwhile, the pollen yolume, and their dimensions. ripens : the anthers open, and the

minute dust is thrown upon the inThe industry of the Bee is prover- sect : at the same time, the needle-like bial, but not certainly more than it de hairs wither; and the insect goes out, serves to be. The visits of insects to laden with pollen, to enter another fowers generally are mutually helpful similar flower in which the surface to flower and insect. They give honey that receives the fertilizing agent is to the insect and cross-fertilization to moist and gummy; and in creeping the flower. The effort of nature to over which the little visitor deposits aroid self - fertilization is, as even some of the pollen, by means of proved by its exceptions, very mani- which the future seed is made ferfest. The pollen is the fertilizing tile. agent. In the majority of cases this is Now, the bee does an enormous borne in the same flower as the seed amount of work in fertilization ; but which needs fertilization in order to in doing this it also does an immense be fruitful. But very special arrange- amount of labour in nectar collectments are made between the flower ing. And it is a very notable fact and the visiting insect to ensure that, that the formation of nectar takes as it secures for itself the nectar place most freely in hot weather, and which the flower contains, it shall is prevented by cold and wet : that bring to the surface to be fertilized the is, it is most abundant when the inpollen of another flower, and take sect is likely to visit. It is from the away the pollen of the one it is then nectar that the bees derive their visiting to give fertility to get another. honey, and it is equally the food of This is, of course, not confined to bees. many insects that do not store it up For example, there is a hedge-flower, as the bee does. The amount of common in the South, known as the sugar contained in the nectar of Birthwort. The flowers are not con- flowers has been recently investispicuous, but are tubular, with the gated; and from Professor A. S. wider end of the tube at the top. At Wilson's analysis, the most remarkthe lower and smaller end of the able facts are made out. Clover may tube the flower expands into a hol- be selected as an example. He found low sphere. In this there is nectar. that one hundred and twenty-five Small insects creep into the tube in heads of red clover gave sixteen search of the nectar; their way is grains of sugar ; or one hundred and somewhat impeded by the presence twenty-five thousand heads gave two all along the tube of needle-like hairs, and one-fifth pounds of sugar. But all pointing downwards, and only on each head contains about sixty florets : this account admitting of the entrance seven million five hundred thousand of the fly. Having once entered the distinct flower tubes must be sucked hollow sphere, the insect finds plenty in order to get two and one-fifth of nectar. But the pollen-bearing parts pounds of sugar. Roughly speaking, -the anthers are not at this time honey contains seventy-five per cent. ripe; they have not opened and emitted of sugar; therefore, five million six

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