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in order to form others with the vital air in contact with them: and such of their principles as cannot unite with the vital air, viz. the earth, some saline and some metallic particles compose the cinder. The new compounds formed are carbonic acid and water; the proportion of these varies according to the proportion of the carbonic particles, and of the hydrogen that had been contained in the inflammable body."

Although this passage describes the effects of combustion with great perspicuity and clearness, yet it may not be perfectly understood by one unacquainted with the principles of chemistry. I shall, therefore, enter more minutely into the subject, and elucidate some of those parts which may not appear perfectly intelligible.

Those substances which we use for producing fire and light, such as coal, oil, wood and tallow, are found, when subjected to chemical analysis, to be compound bodies. They are composed of two or more different ingredients. To these different ingredients, when separated from one another, and obtained in a distinct form, the names oxygen, nitrogen, hydrogen, carbon, &c. are applied. They are also called simple bodies, because, unlike coal, wood, oil and tallow, they have hitherto resisted all attempts to decompound them. Some of these ingredients or principles, such as nitrogen and oxygen, are incombustible; and, on the other hand, those called hydrogen and carbon are combustible. We have, therefore, simple combustible bodies and compound combustible bodies. Some of these components can only be obtained in an aeriform state, such as oxygen, hydrogen, nitrogen, but the carbon may be obtained in the solid state. The simple combustibles are as follow: hydrogen, carbon, sulphur, phosphorus, boron, and the metals.

Combustible bodies cannot of themselves support their own combustion. Certain media are necessary to maintain it; these, consequently, are called supporters of combustion. Thus, common atmospheric air is a supporter of combustion, for combustible bodies burn in it. Whereas, nitrogen gas, one of its constituents, is a non-supporter. Hydrogen gas also, although itself combustible, yet is a nonsupporter of combustion. (Here Mr. Ollivier introduced a taper into a bottle of hydrogen gas; it was immediately extinguished, but the hydrogen was inflamed at the mouth of the bottle, because hydrogen is combustible, but a non-supporter of combustion.)

We have thus seen the relation existing between a combustible and a supporter. It remains now to be shewn, that the combustible is not destroyed by undergoing combustion. But we must first premise that matter has no permanent form. Some elements, which constitute a solid body, may, by changing their state of combination, become gaseous or aeriform. When, therefore, the term gas is used, it is only to denote one of the forms of matter, the same as when the terms solid and liquid are used. The reason, therefore, that the greatest part of the combustible body disappears during combustion is, because the portion which disappears assumes the aerial form, or becomes converted into gas. It has been shewn in the preceding lecture, that it is the oxygen which is one of the constituent parts of air, which enables it to support combustion. This it effects by entering into combination with those constituent parts of the combustible body which have an affinity to, or are capable of uniting with, it. Thus, when coal, wood, tallow, &c. are burned, carbonic acid is formed, because carbon, one of their constituents, combines with the oxygen of the air, and forms a new body, called carbonic acid gas. Water is formed, because hydrogen, another of their constituents, by combining with oxygen, forms water. For water is a compound body, being composed of oxygen and hydrogen. As carbonic acid and water are the results of the combination of carbon and hydrogen with oxygen, and as some combustible bodies exist which contain neither of these principles, it necessarily follows that when such bodies undergo combustion, neither carbonic acid nor water will be formed. Thus, when we burn sulphur, which is considered a simple body, and consequently contains neither carbon nor hydrogen, a compound of oxygen and sulphur is formed, called sulphurous acid, which is the cause of that suffocating sensation experienced during the burning of sulphur. Phosphorus, which is also considered a simple body, forms, by burning, a compound of oxygen and phosphorus, called phosphoric

acid. The latter part, therefore, of the passage above quoted from Berthollet's chemical statics is correct only so far as it applies to the combustion of bodies containing both carbon and hydrogen.

From what has been stated, it must appear evident that the process of combustion, instead of destroying, merely decomposes the combustible body, and sets its several component parts at liberty, in order to form new combinations.

As the combustible, during combustion, combines with another body, and as the light and heat evolved during this process have no weight, it necessarily follows that the product of combustion will be heavier than the original combustible body, in the proportion of the weight of the oxygen with which it has combined. And this is found to be actually the case when the product of combustion is saved. If a candle be suffered to burn in a glass vessel of globular figure, with a trench round the interior of the bottom to receive the water as it trickles down, and the exterior be kept constantly cold by wet cloths, the water only formed by the combustion of the candle, without taking account of the carbonic acid also formed, will be found heavier than the original candle, in the proportion of the oxygen, which has combined with its hydrogen. One hundred ounces of oil, consumed in a similar manner, will form one hundred and thirty ounces of water.

It is also a very remarkable circumstance that all bodies, thus entering into chemical combination, invariably combine in certain fixed and definite proportions. Thus 12 parts of hydrogen invariably combine with 88 of oxygen by weight, to form water; 28 parts of carbon combine with 72 oxygen, to form carbonic acid; so that, when water or carbonic acid are analyzed, they are invariably found united in the above-mentioned proportions. We can, therefore, calculate beforehand how much carbonic and water will be formed by the combustion of a given weight of tallow or oil, supposing the whole of it to undergo combustion.

For this beautiful discovery we are entirely indebted to modern chemistry. It is most happily expressed, says Murray, in the sublime emphasis of the Sacred Record, which refers to Deity in the creation of material things: "He weighed the hills in scales, and the dust in a balance." There is thus proved to be a sublime literality in this extraordinary passage far surpassing the grandeur of orientalism, reserved for these latter days to illustrate. It is thus true that created forms are by weight and measure; and matter, in its multifarious combinations, reveals at length the important truth.

The merit of the discovery that the combustible body always increases in weight, and that the increase corresponds exactly to the weight of the quantity of oxygen gas which disappears during that process, belongs to Lavoisier. This he proved by several experiments. He found that phosphorus, in burning, absorbs more than one and a half its weight of oxygen gas, 45 grains of it consuming 69 of oxygen; and that the weight of the substance produced, during the combustion, exactly equals the sum of the weight of the phosphorus consumed, and oxygen absorbed. He proved the same with regard to sulphur, charcoal, and several of the metals. Thus, in the combustion of 100 grains of iron, he found that 70 cubic inches of oxygen gas were consumed, and the iron had increased in weight 35 grains. But a cubic inch of oxygen gas weighs just one half grain; the weight, therefore, of the 70 inches was 35 grains, corresponding exactly to the augmentation of weight in the iron.

The combustibility of bodies which have undergone combustion may again be restored by abstracting the oxygen with which they have combined. This may be effected by presenting to the burnt body a substance having a superior attraction for oxygen; the new body will deprive the burnt body of its oxygen, and its combustibility will be restored. For instance, if we take phosphoric acid, which is burnt phosphorus, or phosphorus combined with oxygen, and expose it to heat along with charcoal, it will become deoxaggenized, the charcoal will combine with its oxygen and escape as carbonic acid, and the phosphorus will be reduced to its original form. The metallic oxides, in like manner, may, by being exposed to heat along with charcoal, be also reduced to their metallic state. Water is a product of combustion, and its base is hydrogen, a combustible substance. To restore the combustibility of the hydrogen, we have only to abstract its oxygen, which may readily be done by mixing iron or zinc filings and sulphuric acid, with the water; by which means the metal becomes oxidized, and the hydrogen gas is evolved as combustible as ever. Mr. Ollivier then decomposed water by this means, and inflamed the hydrogen as it escaped from the water. The combustibility of metals was also exemplified in the combustion of a watch-spring in oxygen gas, and also of that of a common file with a oxyhydrogen blow pipe.

The combustion of the metal, which was brilliant and striking, afforded a remarkable instance of the energy of oxygen as a supporter of combustion.

In concluding Mr. O. remarked, that the examination of those other subjects connected with combustion, which had not been mentioned, would be reserved for a future occasion.

THE CHAPEL OF LA HOUGUE-BIE, IN THE ISLAND OF JERSEY.

*

THE traditionary origin of this ancient chapel, though shrowded in the legendary lore of the mythology, contained in "Le Livre Noir de Coutances," is, perhaps, not altogether divested of truth. The account we have is, that this part of the island was infested by a monstrous serpent or dragon, which desolated the country. Fired with an ardent desire to destroy the dreadful hydra, the lord of Hambye, in Normandy, undertook the adventurous enterprize, and was successful: but in the conflict, this chivalrous nobleman was apparently suffocated by the pestilential breath of his dying antagonist. The lord of Hambye was attended in this enterprize by a supposed trusty domestic, who, perceiving his master reviving from the effects of this conflict, basely assassinated him. Returning to Normandy with the tragical account that his lord did not long survive the encounter, he presented to the disconsolate widow a letter, which he represented to have been written by her lord just before his death, and which contained a dying request that his bride would recompense the faithful servant by conferring her hand upon him. The artifice prevailed, and the "mourning bride" was united at the sacred altar to the murderer of her husband: but, upon the very day on which the consummation of his villainy was complete, he was suddenly seized with a delirious paroxysm, disclosed the horrid truth, and, on recovering, was tried on his own confession and publicly executed.

The lady, as well to testify her grateful thanksgiving to Heaven for this miraculous deliverance, as to establish a lasting memorial of conjugal affection towards her murdered lord, caused a large and high mound of earth to be raised on the spot where the lord of Hambye was buried, on the summit of which she built a chapel, with so lofty a tower as to be visible from her own mansion at Coutances.

Various reliques, interesting to that learned portion of the insular community "which delighteth" in antiquarian research, have, from time to time, been found among the ruins of the old chapel. We present our readers with the following historical fragment, recently discovered in one of the venerable niches of the large tower.

Oh! list the doleful tragedie,

Which I, with grief, do tell;

Of all the woes and ills, which erst,

A noble pair befel.

This monument of Gothic art

For centuries hath told;

And yet to distant ages will

That dismal tale unfold.

And wakened by these ruined walls,
The muse will oft relate,

The deeds which marked the gallant knight,
And sealed the lover's fate.

In days of glorious chivalrie,
When knighthood did abound,
A dragon, of terrific mien,

Laid waste the country round.
Horror and deadly fear was rife
Throughout the neighbourhood;
For oftimes did this monster prey
On human flesh for food.

The widow's weeds,-the orphan's tears,-
The mother's shrill lament,

Did track the cruel monster's course,
And marked him as he went.

Across the sea, in Normandie,

(Whence sprung our ancient race,)

The rumour of this baneful scourge
Is borne from place to place.
Across the sea,-across the land,—
It travelleth right fast;

Till to the ear of Hambye's knight
It doth arrive at last.

His breast quick kindleth with desire
To meet this deadly foe,
Where honor leads, and danger calls,
He cannot choose, but go.

In vain his lovely bride essaies

To check his youthful zeal;
Too well her fears, her beating breast,
And stifled sobs reveal.

"Nay weep not thus, my onelie life,
"My Athelinda dear;
""Twould surely ill-become a knight
"To bow to woman's fear.

"The Holy Saints in Heaven above,
"Who watch o'er thee and me,
"Will bring me, ere five suns have passed,
"In safety back to thee."

He girds him with his trusty sword,
His lance, and buckler true;

A single page his steps attends,-
His only retinue.

The dragon is probably the impersonation of some piratical marauder, who infested the islands about that time.

(Too little kenned this gallant knight,

That page's perfidie;

And how his black heart then conceived
This doleful tragedie.)

The lady watched their little bark,—
Athwart the wave it flew,

And o'er the billows faintly breathed
Her fond, her last adieu.

Ere five short hours their course had sped,
They reach the destined land,
And villagers in crowds collect,
To greet them on the strand.

"Welcome! most welcome! gallant knight! "Thrice welcome, noble chief!

"Kind Heaven has sent thee here, to prove
"Our sure and firm relief."

Right courteously the knight replied,
And, ere he sought his tent,

He lent himself a willing guest
To village merriment.

The generous goblet circled round,
And all with one accord,

The joyous bumper filled, and pledged
"To Hambye's noble lord."

With the authenticity of this relique, if relique it be, we have little to do beyond informing our candid reader that considerable doubts have been seriously entertained upon the subject. We insert it here simply as a quaint specimen of the crude poetry of the fifteenth century, the age to which it has, by some, been considered as peculiarly belonging.

Four years have elapsed since it was first discovered, and as no successful attempt has since been made to bring to light the remnants of the poem, of which this "trouvaille" is evidently but the introduction, we are driven to one of two irresistible conclusions,-either that they never did exist, or, that they have mouldered in the ruins,-the popular, and perhaps the better, opinion leans towards the former conclusion of this logical alternative, and is supported by the probability that the author may have found more difficulty in killing the dragon with his pen, than did the "preux chevalier " in vanquishing him with his lance.

SION HOUSE ACADEMY, JERSEY.

We have perused with great satisfaction the Annual Report of the proceedings in this educational establishment. The plan is extensive and judicious, and the course of study pursued is marked by sound discretion. Convinced, as we are, that the vast majority of private schools, particularly in the environs of London, are conducted by persons who ought to be pupils instead of teachers, we rejoice that the island of Jersey enjoys the advantage of possessing so able an instructor of youth, as the superintendent of Sion House Academy. He evidently does not teach his scholars by the rule of thumb; nor is he wedded to ancient routine, merely because it is ancient. He has the good sense to obey the spirit of the age, to adapt his system to the wants of existing society, and qualify children to appear with credit and usefulness on the future stage of manhood. The fundamental principle of the plan of education pursued at this academy is the principle of eduction, framed in accordance with the principles of the Baconian or inductive philosophy. We cannot convey a clearer notion of this mode of instruction than by quoting the words of the Report, and placing the ordinary and the new method in juxtaposition.

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TO TEACH

On the usual routine, is to tell a pupil.

1.-To believe.

2.-To believe without examination. 3.-To learn by rote, and repeat with correctness the result of the observations of others. (To learn rules by heart.)

4. To make use of the rules he has learned with confidence, because if he follows them with accuracy he will obtain results that will be true. (To work with the precision of a machine.)

5. To compare the result he obtains with those he should have obtained (with the key), and if his conclusions be erroneous, to retrace his steps and try to discover where he has violated the rule. (Not to despair.)

6. To embody in language the result of his observations, with the utmost precision the subject is capable of.

Lastly. To commit to memory all his conclusions, for the purpose of being able at all times readily to act in conformity with just principles. (To learn rules by heart.)

6. That, seeing he obtained a false result because he forgot one important particular in the rule, he must use means to strengthen his memory, not to be exposed to similar mishaps in future, and that much practice therefore is indispensable to give him, at all times, a thorough competency in every subject of study.

Lastly. To endeavour to find out the reasons of the rules which he has been observing for many years past, for the purpose of satisfying his mind that they have their foundation in reason. (To begin to think.)

The mere perusal of these two compartive statements shows, at a glance, the vast and essential difference between the principle of eduction, and the mechanical jog-trot, rule of thumb routine, pursued in most academies. In teaching arithmetic, for example, how seldom does a teacher explain to the pupil the principle on which any rule is founded! The Tutor's Assistant is put into a child's hand, he reads the rule, learns it by rote as a parrot, proceeds to work out a sum, and when it is fi nished, the child is just as ignorant, as when he commenced, of the rationale of the operation. Take, for instance, the simple rule of multiplication: is it not a mere effort of memory, acquired after repeated trials? Does not every child, in the great majority of cases, consider it a perfectly new and independent rule, sui generis, and unconnected with any other rule? And yet, it is neither more nor less than addition, in a condensed and abbreviated form; but how seldom is this fact made known to a pupil! The arithmetical books currently used in schools are quite unfit for children, and we are happy to find that Professor De Morgan's work, entitled "Principles of Arithmetic," is used at Sion House. Of this excellent publication Dr. Mayo thus speaks, and we fully concur in his eulogium :

"The simple, lucid, and well-arranged treatise of Professor De Morgan is among the happiest attempts to rescue arithmetic from its present degraded state, and to claim for it a place among other branches of rational education. It is peculiarly valuable for young persons, who having been, from their infancy, led hood-winked through the dark alleys of arithmetical rules, desire to take an intellectual view of operations which they have been taught to perform mechanically. It takes them as it where to an eminence, whence they can see the point from which they started, and that at which they have arrived, and, tracing all the windings of the dark passages which they were made to traverse, shews them that they were indeed the shortest, if not the best course they could have followed."

There is a peculiarity in the method of teaching the French language adopted at Sion House Academy, which is excellent: it relates to commercial terms. The phraseology of the counting-house is in all countries dissimilar from that of the drawing-room. The style of a mercantile letter differs toto cœlo from that of a literary epistle, so that an Englishman who can relish the beauties of Fenelon or Racine would be unable to understand a French price current. Of this variance between commercial terms and customary phraseology, the Report contains some striking examples, which we subjoin, as illustrations of technical language, and the importance of learning it.

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