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We will now briefly enumerate some of the advantages which the Colonies and Dependencies enjoy from their connection with Great Distaio. Few words need to be expended on this part of the question, as by those who advocate their dismissal it is admitted that the colonists enjoy a balance of advantage greatly in their favour.

certainly must be a benefit of no ordinary kind, that in their infant and nascent state the colonies should be spared the expense of their own defence, and be secured by the power of the mother country from every external interruption in the development of their energies

. Here, also, may they find capital for their enterprizes at mtes of interest lower than on any other exchange in the world. Here is a market whose gates are never shut for their every production ; factories thirsting for the raw produce which their new tilled lands can give, and where they may purchase at the lowest possible price every manufactured article they can possibly require. The new settlers carry with them a literature the growth of ages, and enriched with the marvellous fruits of a genius as noble as any the world has ever seen. The political experience of generations is theirs, by which to mould the new governments they establish; and principles already confirmed by practice, are prepared for their guidance

. Laws justified by age are already framed by which to mit or determine the rights of every class, or afford rules by which justice may decide all matters referred to her arbitrement. Not less influential or advantageous are those moral and religious entiments which breathe through all ranks in the mother country and dominate all opinion at home, and which, borne to new fields, new climes, or among other peoples, may bear still nobler fruits excellence and virtue in the ages to come, or regenerate an effete ivilization, or give to nations debased by idolatry a new and a vitier intellectual and spiritual life. Our Colonies open a new career for our youth, an honourable held for the display of abilities which in the crowded streets of the hother country

might never find a fitting opportunity. Civilization borne to fields where new conquests may be made, and the arts nd sciences win new laurels. England may rejoice to see her contitation reproduced in new and more perfect combinations, her free egislature transplanted to other climes, and her ideas of respon

government, her impartial tribunals, her personal liberty, her toe thought, and above all her religion, root themselves in wider gions and spread out into mightier realms and empires. These ning kingdoms may well desire to retain a connection so precious

all its features, and, by wise arrangements, continue for many fars to enjoy all the advantages that the settled government of Logland can afford and its power secure, until matured by political experience, strong in numbers and wealth to defend the liberties their parent has fostered and their own experience has improved,

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they may be free from longer tutelage. Arrived at their politic majority they may pursue a career of honourable endeavour, equ ling or even transcending in nobleness and blessed results that of t nation which gave them birth.

But it is asked why may not all these advantages be enjoyed, al yet the mother country be free from the cost of securing then Why should the English at home be taxed for colonies which a rising in wealth, and employing their security and their light burde for their own sole advantage ? In reply to the latter question it h been shown that the Colonies, as a whole, more than repay the cost; and that answer might suffice. But the example of t| American protective tariff, followed in some measure by Canad proves, that when independent these colonies may adopt princip of commercial legislation directly antagonistic to the interests of t| mother country. While the connection subsists, and the hon government retains the power of disallowing colonial ordinance there will remain the opportunity of preserving an uniform code commercial law, and a restraint be placed on selfish and narro minded legislation. Already this tendency has become apparent the Colonies where local legislatures exist. No independe nation has yet followed the free-trade legislation of Great Britai and indications are not few that our Colonies would revert to t system of protection were they freed from the ties that bind the to the mother country. Because our trade with the United Stat has grown to large dimensions since their independence, it does n follow that other colonies would in similar manner expand the trade with England. But for its inimical tariff, there can be 1 doubt that our American trade would have expanded to mo gigantic proportions ; and it is because we cannot secure ou selves against hostile tariffs on the part of independent nations, th it continues to be necessary to our trade and manufactures that y should retain some hold on our Colonies, where an open market mi be preserved.

Less appreciable, perhaps, but certainly not less important to of Colonies, are those moral, intellectual, and religious influences whit the connection enables Great Britain to exercise, and which woul be largely diminished by separation.

An independent people is naturally jealous of interference. Th United States have shown us enough of this, and our Colonies to where we have seemed to them to overstep the bounds of moderi tion. But the free interchange of thought and pursuit which no goes on between the mother country and her colonial children, cox tributes greatly to their growth, and which, to a certainty, woul undergo diminution in case of severance of interests, even if it di not degenerate into actual antagonism.

We do not enter here on the question of the disadvantage

which may rise out of a state of war, both to Great Britain and her dependencies. War is, or ought to be, an abnormal state of things, and its effects will be as varied as is the position of the colonies, and the nation with whom war is being carried on. Our Colonies would need protection, and be a cause of weakness to

only in the case of war with a great maritime power. In a continental war they would add to our strength.

We seem then to have been brought to the conclusion, that the sdvantages enjoyed by the Colonies of Great Britain and the mother country from their connection are many, and that under present circumstances, the lifting the colonies into independent nations would be productive of injury to both.

A MESSAGE FROM THE SUN.

coloured.

Ir during bright daylight you darken a room by closing the shutters

, and then bore a small hole through one of those shutters, you will observe on the opposite wall a patch of white light. This patch will vary in size according to the size of the hole and its distance from the wall. But it will always be round (if the hole be sound), and will always consist of white light, and will therefore only appear coloured according as the paper covering the wall is If

, now, you take a prism, or triangular piece of glass (such as hang down from chandeliers, or are often used as knife rests at table)

, and place one side of it over the hole, close to the shutter, either on the outside or inside, it does not matter which, you will find that the patch of light has become oblong instead of round; and instead of being white, is now made up of seven bands of seven different colours, placed in a fixed order one after the other, red, Grange, yellow, green, blue, indigo, and violet, all distinct, and yet toned down so as to mingle well one with the other. This patch is what philosophers call a spectrum. You can always make it appear by following the above directions. It is altogether caused by the shape of the prism. Nothing but a prism will do. But it 3 not necessary that the prism should be made of glass. Other transparent bodies will do, some as well, others better, others not The spectrum I have described, being obtained from sunlight, is called a solar spectrum. But you may get the same oblong

to well.

spectrum, with the same coloured bands, from any of our usual artificial lights. If, for instance, you allow a bright gas-light, after passing through a small hole and a prism, to fall upon a white screen in a dark chamber, you will get a spectrum apparently exactly like the solar spectrum ; and the same with an oil-lamp, and the drummond, or the electric light. With all these you will get what are called artificial spectra, apparently exactly like the solar spectrum.

I say apparently, because in reality there is a very great difference, which, however, can only be detected by very careful eramination. If your hole be very small

, and especially if instead of being round, it be a mere slit with very thin edges, and if you the light fall, not on a wall, but on the front of a telescope of moderate power, and having placed your eye at the other end, carefully adjust the focus of the instrument, you will find that in the solar spectrum there are a very great many dark bands or lines passing across it, but in the artificial spectra you will find no such lines. If you take an ordinary plain white ivory paper-knife, and colour it with bands of various colours, beginning with red at the bottom of the handle and ending with violet at the point, that will give you a very fair idea of the spectrum, as seen when the light is sent through a slit. If now, with lead pencils of various blackness, you draw ever so many parallel lines across your spectrum from side to side, making some broad, others fine, some dark, others light, crowding them together in some parts, letting them be wide apart in others, you will have a good representation of the dark lines which are seen in the solar, but in no artificial spectrum.

These dark lines are called Frauenhofer's lines, because it was he who discovered them. They are perfectly constant, always 10 be found in sun-light, are not in any way caused by the nature or quality of the prism, have each their fixed place in the spectrum so that they can be named and recognised, and their distances from each other, or from the ends of the spectrum, or from any particular point of it, accurately measured. For instance, there is one particular line in the yellow space, which they call D, and another in the red called A, and between the two, there are a fixed number of other lines at fixed distances, each of a fixed breadth and darkness. Wherever there is sunlight, there, if you look for them, you may find these lines. They are the letters, the hieroglyphics of the sun's message to the earth, and for a long while men wondered what their neaning could possibly be.

But within the last few years our philosophers have learnt to spell out something of these strange symbols, and the way they managed it was as follows: The spectra of our artificial lights have, as I said, no dark lines, and are therefore called continuous ;

for the lines being merely spaces where light is altogether absent, when they are away the light reaches without break from one end of the spectrum to the other.

Our artificial lights are prized for giving a comparatively white light

, and the whiter the light the more they are valued. But there are many substances which, when burned, give a light having a very marked colour. Thus the metal sodium (as, for example, it occurs in its compound chloride of sodium, which we generally call table salt) gives a yellow light; the metal barium a green; copper also a gTeen ; strontium a red; potassium a violet; and so on. These facts are well known to firework makers, and are often of use to ehemists in ascertaining the presence or absence of any particular body.

if now a white light gives a continuous spectrum with all the colours from red to violet, what sort of spectrum can we expect to have from a yellow or red light, or from a light having any particularly definite colour ? The answer is that only that part of the spectrum is visible which corresponds to the colour of the light. Thus with a yellow light, we see only the yellow part of the spectrum, all the rest being invisible; with a red light, we only see the red, and so on, the yellow being in exactly the same place as the yellow part of the spectrum would be if the whole of it were visible. And the other colours in the same way. If however we etamine our results with greater care and delicacy, we shall find a more curious result. Let us take a good prism, a good telescope, and a very faint light, such for instance as a spirit lamp with the alcohol so diluted with water that it will only just burn. We shall then get only a very faint spectrum. If now we introduce a little table salt into the flame of the spirit lamp, we shall get a yellow fame, and if we look through the telescope we shall find not a yellow light all over the yellow space of the original spectrum, bat only one narrow bright yellow band across one particular part of it. Repeat the experiment as often as you like you will always get the same result. Hence this bright yellow band in one particular part of the yellow space is called the “sodium spectrum.If

you had a substance, of whose nature you were ignorant, and were to burn it in such a flame as I have described, and found it gave that bright yellow band in that particular place, that is to say, gave the sodium spectrum when viewed through the spectroKope

, (for such is the name given to the arrangement of prism and telescope) you might say without any fear at all of error that the substance contained sodium. If instead of sodium we burn in the flame a small quantity of the metal lithium, we shall find a red band produced in another particular part. And this red band will be the only thing we shall see, the rest of the spectrum being

This red band is then the lithium spectrum, and by it we can recognize the presence of lithium.

invisible.

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