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personage; his locks hoary with age, and clothed in a long loose gown; a leathern girdle was about his loins; his beard thick and grizzly; a large fur cap on his head, and a long staff in his hand. Struck with astonishment, I remained for some time motionless and silent: the figure advanced, staring me full in the face. I then said, 'Whence and what art thou ?" " "What was the answer?-tell me what was the answer?" "The following was the answer I received, 'I am watchman of the night, an't please your honour, and made bold to come up stairs to inform the family of their street door being open, and that if it were not soon shut, they would probably be robbed before the morning.""

To bring my paper to a close, how evident is it to every sound-thinking person, that man cannot always rise superior to that weakness which often dwells within, and which, by a polluted and perturbed imagination, is so swayed as to regard all things superstitiously: this weakness has produced evils, great in their results-has rendered man miserable-has placed in a more prominent light his failings, and caused a smile of ridicule in many instances.

REMARKS ON ILLUMINATION.-II.

THE fact that highly-carbonized substances may be conveniently used as fuel for lamps having been once established, numbers of such substances have since been so employed. Of these, naptha was one of the first to be introduced, but owing to its extreme volatility, a change in the form of the lamp became necessary; for had the naptha been contained in a vessel on a level with the burner, or but slightly below it, as in oil lamps, the heat would have been sufficient to cause the formation of a large quantity of vapour, and produce an explosion. To avoid this, the naptha is placed in a vessel at some distance (say about two inches) below the top of the burner, the tube and the cotton it contains being made sufficiently long to reach to it. In this lamp the flame is flat, the cotton being plaited up so as to resemble a piece of tape; and the flame is supplied with air by means of an oxidator, somewhat as in the solar lamp, but of course made also flat and rising only to a level with the top of the cotton, not extending above it, and partially intersecting the flame as in the solar. The chimney is in the form of the frustrum of a cone flattened.

These lamps, on account of the flat shape of the flame, never became generally used in private houses, as the light is thrown strongly on two sides, and but little on the others, where the narrow edge of the flame is all the surface it has to proceed from. Endeavours to use naptha in a round argand burner were long ineffectual, as it was found necessary to have an oxidator at each surface of the flame to consume the large amount of carbon which it contains.

The camphine, lately so much used, is a liquid of much the same description, as regards its applicability to illuminating purposes, as naptha, and the description of argand burner which has been invented for its consumption, would doubtless do equally well for that fluid. Camphine, we may as well state, is nothing more than very highly-rectified oil of turpentine. The great peculiarity of the camphine burner, consists in the form which is given to the flame, by placing a sort of button in the middle of it, and contracting the chimney immediately below it; the

Fig. 1.

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effect of this will be best seen by referring to fig. 1, in which a a represents the tube of an argand burner, bb the cotton (both made long, as in the case of the naptha lamp, to allow of the volatile fuel being at some distance below the flame), ce a ring made of perforated brass to admit a large supply of air through the oxidator, dd which stands upon it, reaching only just above the top of the cotton and not intersecting the flame; e is the button, supported by a small rod fastened in the centre of the burner; ƒ the chimney, and GG the flame. Now it will be seen at once, that the flame is spread out horizontally by the button, so as to be brought just over the stream of air which rushes through the contraction of the chimney, a perfect mixture of the air with the camphine vapour being thus insured; the large number of particles of carbon contained in a small quantity of this vapour giving rise to a very dense and bright flame. So far this looks well for the lamp; but when we consider that it is impossible to make more than a certain quantity of air pass through the oxidator in a given time, and that the quantity of carbon consumed, is in proportion to the quantity of air supplied, we are forced to the conclusion that a much smaller quantity of camphine or naptha vapour must be used than if we employed a less carbonized substance, as oil; and such we find in practice to be the case: the consequence is, that though the flame is bright, it is very small; in the best camphine lamps never being more than three-quarters of an inch in height without smoking, while in an oil lamp it may reach as great a height as three inches, which, though at no one point so bright as the small flame, will, on account of its greater size, throw a really larger amount of light over the room. Various inconveniences also result from the peculiar shape of the flame; in the first place, the light, instead of being dispersed sideways, is thrown almost entirely upwards and downwards; that which is thrown upwards being, to a great extent, intercepted by the button in the centre of the flame, we lose the effect of reflection from the ceiling, which so materially assists in illuminating an apartment; we have thus a very bright, indeed dazzling light, upon the table, with even less light than usual at all other parts of the room, which is extremely bad for the eyes. This very bright light on the table has caused the assertion that much more light is given by a camphine than an oil lamp; but we have found, by careful trials, that in a large room a small print could be read at a much greater distance from the latter than the former. Another and not slight inconvenience is, that the chimney being brought very close to the flame, becomes greatly heated, and radiating its heat in all directions nearly in a line with the heads of those seated at the table, gives rise to many unpleasant sensations.

The first of these objections might doubtless be got over by some alteration in the form of the lamp which would allow of a larger supply of air, and thus give a larger flame; and in very large and well-ventilated places, such a lamp might be valuable; but the large quantity of carbonic

acid to which it would give rise, as well as the very great increase of heat, would make one regard all such additional light, in an ordinary apartment, as so much poison. The light of these lamps appears at first sight so much whiter than that of oil, that we are inclined to regard it as something superior; but this apparent whiteness will be found, on closer examination, to arise from an absence of red rays, and not from a proper adjustment of all the colours as in really white light. This is readily demonstrated by observing the dulness of all red or pink colours when viewed by it. On this account also the complexion assumes the same sort of livid appearance which it is well known to present by gas light, in which there is the same absence of red rays. We have said thus much of these lamps because convinced that many are led away by the brightness of the flame to use a lamp which will ultimately prove injurious to that invaluable organ—the eye.

A lamp has been lately introduced into this country from Paris, which promises to excel almost all those at present in use, as it gives a remarkably pure light, and does away with almost all the trouble of trimming, having no wick: in fact, it is a self-generating oil-gas lamp. It is represented in fig. 2, and consists of a vessel, A, to hold oil, with a tube coming from the bottom of it, just as in an ordinary landing lamp; into this is screwed a small tube b, perforated in several places near the top, and provided with a stop-cock, c, at bottom to regulate the supply of oil: just under the perforations in b is fastened a metal cone dd, with an edge turned up at bottom, into which is accurately fitted the bottom of the larger cone e e, which is perforated with small holes like a gas burner, all round, as shown by the dotted line ƒ; G is the gallery for the chimney H, and ii the flame; K is a small cup holding about a teaspoonful, fastened on to b. When it is required to light the lamp, a little tow or a small piece of rag is wound round the cone d d, and e e is then placed over it; a little spirit is poured into K, and the cock e partly opened; the spirit is then lighted; and the oil flowing out of the holes in b, soaks into the tow, and comes in contact with the cone dd, now made hot by the burning spirit ; it there becomes decomposed and gives out oil-gas, one of the best kinds of carburetted hydrogen; this issues through the holes in ee, and burns just like a gas flame, at i i, which flame serves to keep the cone hot after the spirit has gone out. The advantages of this lamp are too manifest to need mentioning, as the only attention it requires is to fill up the oil vessel, and occasionally to change the tow about dd. The lamp shown in the figure is the only form that has yet been sent to this

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Fig. 2.

country, and is only fit for a landing or other place where beauty is not much studied. There was a little difficulty at first experienced in in making them sightly enough for the drawing-room, but we are

informed that this has now been quite overcome, and that they are much used in Paris, and will shortly appear here. The principle can, however, be as well seen in such a lamp as the one we have figured, as in any other.

We have now noticed the principal lamps for burning fluids, or rather their vapours, which can be applied to domestic purposes. Bude light, and all such as are only fit for large public buildings, having been purposely omitted. In our next we propose noticing the principal varieties of gas burners.

Prize Essay.

SCIENCE CONSIDERED AS AN AGENCY FOR THE
PROMOTION OF CHRISTIANITY.

BY STUDENS.

It is no longer incumbent on the religious professor, amid the many turmoils and difficulties that beset his path, and amid all the errors that threaten to mislead his understanding, to prove that Science is unopposed to Religion. The specious sophisms put forth by sciolists as running counter to the statements of scripture, have long since been consigned to oblivion, so utterly inconsistent were they with the facts revealed by an experimental investigation into the phenomena of nature. The recollection of the unconfirmed and imaginary notions of Volney, so pompously pourtrayed in his "Ruins of Empires," in reference to the primeval condition of mankind, or of the silly bombasts of the pseudophilosopher Voltaire, are of use now simply in provoking a smile. It now stands forth to the world as a broad truth, that the most profound and successful inductive philosophers hold with the most tenacious grasp the glowing truths of Christianity. It must not now be affirmed by any, that Christians fear the searching furnace of scrutiny, though seven times heated; they pant for the universal diffusion of physical knowledgefit harbinger of the honest and uncompromising morality of the gospel, -because into this department of enquiry no bewildering errors can creep here men's senses are the test; here is brought to light stern and unalterable fact; here nature will not be tampered with or moulded according to the desires and wishes of the human heart; and consequently here must be found, if not a powerful coadjutor, at least by no means an opponent or a foe-and a faithful and powerful witness has she proved herself of God's truth. She declares that the system of ethics and moral government to be deduced from her revelations, are strictly in accordance with the holy Word. Her devoted admirers and most ardent worshippers who have neglected the gracious teachings of Nature's mighty Author, and who have called into dispute the justice of Heaven's schemes, she has totally abashed. The stormy ocean has engulphed in its roaring billows the tempest-tost mariner, and the

SCIENCE AN AGENCY FOR THE PROMOTION OF CHRISTIANITY.

77 shrieks of the dying victims have been heedlessly swept away by the bellowing winds, as they have sunk to rise no more. The volcanic mountain has been convulsed with her dreadful heavings, and has madly belched forth her liquid fire, entombing in one smoking pile the fairest and most lovely of the human kind and the proudest monuments of man's immortal genius. The poor and feeble frame of the emaciated sufferer has been racked with agony inconceivable, and though the glazed and dying eye has been uplifted in profoundest humility to the Ruler of the universe, yet no answer of peace has been apparent, and still has life held on, and still have the torments increased. And now having witnessed these terrible expositions of his blasphemous assertion, will he dare stand out and utter forth his complaints against the judgements recorded in the sacred volume? will he dare give forth the lie and appeal to Science for its confirmation? Science will laugh him to scorn-will point him to Nature's answer in the moanings of her immolated victims-in the cruel hurricane-in the pestilential plague! By Science, then, we are enabled to discover the perfect and complete analogy existing between the teachings of revelation and the laws of nature. Nature is the practical working of the gospel's forecast and pre-existent plan.

Without entering into a detailed account of the admirable manner in which the memorials of Scripture, in reference to the creation of our earth and the subsequent changes of its outermost strata, as well as the common origin of the human race, are demonstrated by the researches of scientific men, which, indeed, can be learnt far better elsewhere; we are desirous of briefly reflecting on the influence of Science on the future progress of Christianity. It is declared, "That the knowledge of the Lord shall cover the earth as the waters cover the channel of the mighty deep;" and while pondering on the glories of that blissful day, and catching a far distant glimpse of its perfect brightness and heaven-born peace, we perhaps may indulge unwarrantable speculations; yet seeing how Science has stood forth as the unflinching champion of religious truth, we cannot but imagine that she is destined to occupy the fore-front amongst the honoured instruments that are to be employed in the scheme of universal redemption. We know that Christianity has availed herself of the finest discoveries of by-gone times; that the art of navigation has been employed to convey the missionaries of the Cross, and the word of truth across the waters of the trackless deep-that the needle has been true to the Pole, not as the guide of the anxious merchant alone, but as the director of those who bear the heavenly magnet. We know that the labours of self-denying investigators have been at the service of Christians, and have been employed without hesitation for the furtherance of Christianity; and we may without presumption assert, that in the vast design of God's providence, such men as Columbus, Magellan, Drake, or our great circumnavigator Cook, were forging links in the chain of events that will ultimately issue in the moral renovation of our globe. Apart from Science, and independent of its aid, Christianity would never have been promulgated beyond the immediate sphere of its first communication,

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