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Combustion is the evolution of heat, through the rapid chemical union of a supporter of combustion with a combustible body. There are five supporters of combustion; namely, oxygen, chlorine, and the vapours of iodine, bromine, and fluorine. Of these, the first is by far the most important, owing to its constant presence and interference, as a constituent of the atmosphere. When oxygen combines slowly with any other body, as in the rusting of iron, and tarnishing of lead exposed to the atmosphere, there is heat evolved in a very gradual manner; but it is dissipated, and never accumulates. Here we say that oxidation takes place. But when this combination takes place rapidly, as when iron is exposed to oxygen in a state of ignition, that is, red hot, it is said to be burned, and to suffer combustion; the product, namely, oxide of iron, being the same in both cases,-only in the latter its formation is attended with a sensible evolution of heat. The affinity of oxygen for combustible bodies is greatly promoted by heating the latter; but when the combustible body is once inflamed, it maintains itself sufficiently hot to continue burning till it is entirely consumed. If the heat evolved be in sufficient quantity, it renders the body luminous or incandescent; that is, it emits light, as well as heat. The combustible constituents of wood, coal, oils, tallow, &c., which enter into combination with oxygen, are the same, namely, carbon and hydrogen, which in combining with oxygen, at a high temperature, produce carbonic acid and water; and these, being volatile, disappear, forming part of the heated aerial column that rises from the burning body. No loss whatever of ponderable matter occurs : nothing is annihilated. If the gaseous products given off, and the ashes remaining, be collected, they will be found to have exactly the same weight as the oxygen and the combustible body which have disappeared. We may see the effects of heat in disposing oxygen to unite with a combustible body, when a supply of coals is laid on a fire: until they become sufficiently ignited, combustion only goes on to an imperfect degree; the whole of the combustible ingredient of the coal is not consumed, part passing off as smoke. If you promote
a more liberal supply of oxygen, by stirring the fire, or, better still, by using the bellows, the whole is soon ignited, and the smoke as soon diminishes. · When this takes place, the whole is rendered luminous; that is, light is emitted as well as heat. If I blow out the candle, combustion goes on for a few minutes, to a slight degree, and the whole of the carbon from the tallow is not consumed,
off as smoke: but on applying a light, the chemical union of the oxygen and carbon is more rapid; the whole of the latter is consumed, and the combustible body becomes luminous. You may see that the smoke is unconsumed carbon, by applying the light an inch or two above the wick, when the flame will descend to the wick. The ascent of the melted tallow along the wick affords, by the way, a good example of what I before spoke of as capillary attraction.
(To be continued.)
SAXON HUSBANDS AND BRITISH WIVES. THE Saxons had never been refined by peaceful approximation to the Roman frontier. No Missionary had set his foot among their forests or on their coasts. They were Pagan pirates. They invaded Britain by detachments, and under different independent Chiefs. They never landed in such imposing force as to awe the invaded into bloodless submission, but merely in sufficient numbers to fight their way; to conquer indeed, but only to conquer inch by inch. Their savage Paganism inflamed them with peculiar frenzy against all that the Christianised Britons held most sacred; each side upbraided the other with perfidy and fraud; no possible bond of fair union existed between them; and, probably, in no conquest were the victors more ruthless to the vanquished than in the desperate and chequered struggle by which the Saxons won their slow way over this island.
Led by this historical circumstantial evidence, and by the great fact of our language being essentially Germanic, I believe that the Saxons almost entirely exterminated or expelled the men of British race whom they found in the parts of this country which they conquered. But the same evidence, (both the historical and the philological,) when carefully scrutinised, leads also to the belief that it was only the male part of the British population which was thus swept away, and that, by reason of the unions of the British females with the Saxon warriors, the British element was largely preserved in our nation. I remind my readers that the British, whom the Saxons found here, were mainly Celts.
Besides those Celtic words in the English language which can be proved to be of late introduction, and those which are common to both the Celtic and Germanic tongues, there are certain words which have been retained from the original Celtic of the island. These genuine Celtic words of our language (besides proper names) are rather more than thirty in number. The late Mr. Garnett formed a list of them; and in his opinion the nature of these words showed that the part of the British population which the Saxons did not slay, was reduced into a state of complete bondage, inasmuch as all these words have relation to some inferior employment. Now, if the reader will carefully examine the list, he will see that not only do these Celtic words all apply to inferior employments, but that by far the larger number of them apply to articles of feminine use or to domestic feminine occupations. They are as follows:Basket, barrow, button, bran, clout, crock, crook, gusset, kiln, cock (in cock-boat), dainty, darn, tenter (in tenterhook), fleam, flaw, funnel, gyve, griddel (gridiron), gruel, welt, wicket, gown, wire, mesh, mattock, mop, rail, rasher, rug, solder, size (glue), tackle.
This remarkable list of words is precisely what we should expect to find, on the supposition that the conquering Saxons put their male prisoners to the edge of the sword, except a few whom they kept as slaves, but that they took wives to themselves from among the captive daughters of the land. The Saxon master of each household would make his wife and his dependents learn and adopt his language ; but in matters of housewifery and menial drudgery, their proud lord would scorn to interfere, and they would be permitted to employ their own old familiar terms. All the circumstances of the Saxon conquests favour this hypothesis. The Saxons came by sea, and in small squadrons at a time. They came also to fight their way, and were little likely to cumber their keels with women from their own shores. A few Rowenas may have accompanied the invading warriors, but in general they must have found the mothers of their children among the population of the country which they conquered.
This hypothesis also accounts for the difference which undoubtedly exists between ourselves and the modern Germans, both in physical and in mental characteristics. The Englishman preserves the independence of mind, the probity, the steadiness, the domestic virtues, and the love of order which marked his German forefathers; while, from the Celtic element of our nation, we derive a greater degree of energy and enterprise, of versatility and practical readiness, than are to be found in the modern populations of purely Teutonic origin.-- Creasy.
TRIAL BY JURY. It is but a few years since an English writer, by proffering a eulogy on trial by jury, would have laid himself open to a remark, like that of the Spartan's to the rhetorician, who volunteered a panegyric on Hercules : “Why, who ever thought of finding fault with Hercules ?" But now the fashion has sprung up of sneering at the decisions of jurors; and we continually hear of schemes to transfer the duty of pronouncing on disputed facts from the jurybox to the bench. Juries are, of course, liable to error ; and, when they err, their blunders are made in public, and draw at least a full share of notice ; but, on the other hand, we should remember the invariable honesty, and the almost invariable patience, with which juries address
themselves to their duty. No spectacle is more markworthy than that which our common-law courts continually offer, of the unflagging attention and resolute determination to act fairly and do their best, which is shown by jurors, though wearied by the length of trials, which are frequently rendered more and more wearisome by needless cross-examinations and unduly prolix oratory. The juries of our agricultural districts, with a good share of smockfrocks in the jury-box, (the constant object of the small whispered wit of pert professionals,} deserve to be studied as proofs of how much worth is veiled in low estate in England, which trial by jury calls into action. The thoughtful observer of their enduring zeal in the unpaid discharge of a burdensome function, must reverence, from the very depth of his heart, the twelve plain, good, and lawful men before him ; “the sturdy, honest, unlettered jurors, who derive no dignity but from the performance of their duties.” Such generous fulness and fairness in hearing and thinking before deciding are not found in any other tribunal. Another inestimable advantage peculiar to jury trial is, that it is not known beforehand who will be the jurors in any particular case; so that there is no time given for the work of corruption. It is hardly known, even at the trial, who the individual jurors are; and when the trial is over, the members of the jury are dispersed and lost sight of amid the mass of the community. Hence they are, while acting, exempt from all bias of fear, and from all selfish motive to favour. And not only are they peculiarly free from all evil influences upon their integrity, but they are free from the suspicion of being so influenced. The people have full confidence in their honesty. The same amount of confidence (whether deserved or not) would not be accorded to permanent paid officials: and there is truth in the seeming paradox of Bentham, that it is even more important that the administration of justice should be believed to be pure, than that it should actually
Nor are the errors of judgment which juries fall into by any means so numerous as the impugners of the system assert. The jury generally know what they are