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FAMILIAR ILLUSTRATIONS OF NATURAL | ration depends upon the temperature; so that if, on

PHENOMENA.

No. XV. WATER IN THE STATE OF VApour. WE are so accustomed to see water in a sensible form, either fluid or solid, as in rain, ice, hail, snow, fog, and the like, that every one is surprised when he is made conscious, for the first time, that water may really be found in the condition of a perfectly invisible vapour. Yet, whoever has seen a bottle brought out of a cellar in a warm day, or observed the effect produced, when the windows of a carriage are first drawn up, and particularly persons wearing spectacles, the glasses of which are suddenly dimmed by steam upon entering a heated room, must have noticed enough to convince him that such is the case. In such instances, the colder surface of the glass condenses the vapour of water, previously invisible in the atmosphere, and thereby renders it sensible. All the great changes of sunshine, cloud, and storm,—the various hues of the rising and setting sun,-the halos which occasionally surround the sun and moon,-are all influenced or occasioned by the vapour of water diffused throughout the atmosphere.

The vapour of water, however, in its simplest form, is perfectly invisible. It exists, as we have seen in a previous number*, mixed with the other gaseous matters which compose the atmosphere, and diffused over all parts of the earth's surface. Every substance which contains water is capable also of permitting it to evaporate. Not only large masses of water, as seas, lakes, and rivers, as well as ice, but every portion of vegetation, all soils, even those which appear the driest, are continually permitting some portion of watery vapour to escape from them. The quantity of vapour in the atmosphere at any given time is influenced by a variety of causes; but the presence of such a vapour is most important for many purposes. Dew, which is formed by the condensation of the vapour of water upon the leaves and other parts of plants †, affords nourishment to vegetation when no rain falls; and a certain quantity of vapour of water is essential to the health of man. In some hospitals, when they were first warmed by heated air, it was found that the inmates suffered from their skin cracking and peeling off, as in very hot climates; but the inconvenience was immediately removed, when vessels of water were placed in several parts of the building, which, by evaporation, supplied the requisite quantity of moisture to the air.

The quantity of evaporation going on constantly is far greater than is usually conceived. In a hard frost, a lump of ice or snow will be observed sensibly to diminish, especially if a brisk wind is blowing over it. This is quite independent of the wasting of the frozen substance by thawing. In fact, snow or ice may totally disappear, without any perceptible thaw, simply by evaporation. It has been computed, from actual experiment, that an acre of snow evaporates four thousand gallons of water in twenty-four hours. All plants exhale vapour; and some much more than others. Thorn hedges exhale seven times as much as those of holly; and a cabbage perspires six or seven times as much as a man from the same quantity of surface.

There is, however, a limit to the power of evaporation; and this limit is fixed by the temperature of the climate. We are very imperfectly acquainted with all the causes which occasion the difference of temperature in different places: but we know that there are certain extremes both of cold and heat which are not surpassed. Now the quantity of evapoSee Saturday Magazine, Vol. V., pp. 103, 149, 236. Ibid. Vol. IV., p. 117.

the coldest day of winter, the air contains as much moisture as possible, or is, as it is called, saturated with vapour, it can then receive no more vapour, unless its temperature is increased. But as the temperature of the air increases, more and more vapour may be mixed with it; yet still, as the heat of the air never exceeds a certain degree, the quantity of vapour also is limited.

Such a limitation is quite necessary for the wellbeing of all plants and animals: either a perfectly dry air, or an atmosphere which was overcharged with vapour, would be inconsistent with their existence in a state of health. As the atmosphere is now constituted, there is found in every part a certain quantity of vapour, ready to make its presence sensible whenever any change of circumstances causes it to be condensed.

One of the most common effects thus produced is that of clouds. The well-known experiment, mentioned above, of the condensation of vapour on a cold surface, such as glass, shows that if the temperature of the air be by any means lowered, the quantity of moisture which it will retain in the state of invisible vapour will be diminished. In cold weather, this is made very evident by the condensation of the breath of animals. The air, which comes from the lungs, contains with it a quantity of watery vapour, which would be quite invisible if it were breathed out into an atmosphere of the same or nearly the same temperature as that of the animal's body. But when the air is much colder, some of the vapour is instantly condensed, and forms very small drops. The same effect is seen on a large scale when the steam is discharged from a steam-engine. Where, then, any change takes place in the temperature of the atmosphere, from any cause, there is a probability that the vapour in the atmosphere will be condensed, and become visible.

Thus, suppose the air perfectly serene and clear, and that it contains in every part just as much vapour as it is then capable of containing. If a stream of colder air be now made to pass through a part of this atmosphere, the temperature of the two portions of air when united will be lower than that of the first portion was before, and the vapour in it will be partially condensed, forming a cloud of greater or less density according to circumstances.

If the condensation goes on, the very small particles of water,-which float in the atmosphere, or, after descending a little way, meet with a warmer temperature and are again turned into invisible vapour,—will unite in drops of a sensible magnitude and fall in rain. Should they meet with a still greater degree of cold, the drops freeze in their descent, and appear as hail: or, if the congelation takes place while the particles of water are still very small, snow or sleet will be formed.

By the same means all the different appearances of fog and mist are occasioned. During the heat of a summer's day, evaporation goes on with great rapidity, as has been already noticed, from water, from all vegetable bodies, and even from the earth. But, at sunset, heat begins to be lost by radiation, and some of the vapour is immediately perceptible, especially where evaporation has been most copious, as along a river, or over meadows. The course of a river may sometimes be distinctly traced for a long distance, even when the water itself is not visible, by the fine cloud formed by such congelation.

On the other hand, when the atmosphere is charged with visible moisture, an increase of heat converts the water into invisible vapour. A very beautiful

instance of this effect is often seen in Autumn. At sunrise, the whole atmosphere appears full of floating particles of water, forming a dense mist, the minute drops of which are distinctly visible. As the sun rises above the horizon, the air is gradually warmed: the fog begins to disperse, at first rising a little into the forms of clouds, but soon totally disappearing.

The causes which occasion many of the changes of water from the state of vapour to a visible form, and the converse, are not well understood. Electrical agency appears to be very active; and there are probably many other causes. But what is here stated may be enough to show how many beneficial consequences flow from the wise provision which is made for the extensive diffusion of water in the state of vapour.

C.

THERE is nothing in history which is so improving to the reader, as those accounts which we meet with of the deaths of eminent persons, and of their behaviour in that dreadful season. I may also add, that there are no parts in history which affect and please the reader in so sensible a manner. The reason I take to be this, because there is no other single circumstance in the story of any person which can possibly be the case of every one who reads it. A battle or a triumph are conjunctures in which not one man in a million is likely to be engaged; but when we see a person at the point of death, we cannot forbear being attentive to every thing he says or does, because we are sure that, some time or other, we shall ourselves be in the same melancholy circumstances. The general, the statesman, or the philosopher, are perhaps characters which we may never act in; but the dying man is one whom, sooner or later, we shall certainly resemble.ADDISON.

LET us at all times cherish in our minds an unrelaxing certainty, that we shall always find the Almighty perfect in his justice to us all, and in everything, and individually to each of us, as soon as we obtain sufficient knowledge of his operations with respect to us. Let us wait with patience until what we do not perceive or cannot comprehend shall be satisfactorily elucidated to us. We expect this equity and consideration in our intercourse with each other. Let us also so conduct ourselves, in all our thoughts and feelings with reference to Him, whatever may be his present or future dispensations personally to ourselves.-TURNER.

INSENSIBILITY, in return for acts of seeming, even of real, unkindness, is not required of us. But whilst we feel for such acts, let our feelings be tempered with forbearance and kindness. Let not the sense of our own sufferings render us peevish and morose. Let not our sense of neglect on the part of others induce us to judge of them with harshness and severity. Let us be indulgent and compassionate towards them. Let us seek for apologies for their conduct. Let us be forward in endeavouring to excuse them. And if, in the end, we must condemn them, let us look for the cause of their delinquency, less in a defect of kind intention, than in the weakness and errors of human nature. He who knoweth of what we are made, and hath learned, by what he himself suffered, the weakness and frailty of our nature, hath thus taught us to make compassionate allowances for our brethren, in consideration of its manifold infirmities.-BISHOP MANT.

No obligation to justice does force a man to be cruel, or to use the sharpest sentence. A just man does justice to every man and to every thing; and then, if he be also wise, he knows there is a debt of mercy and compassion due to the infirmities of man's nature; and that is to be paid: and he that is cruel and ungentle to a sinning person, and does the worst to him, dies in his debt and is unjust. Pity, and forbearance, and long-sufferance, and fair interpretation, and excusing our brother, and taking in the best sense, and passing the gentlest sentence, are as certainly our duty, and owing to every person that does offend and can repent, as calling to account can be owing to the law, and are first to be paid; and he that does not so is an unjust person.-JEREMY TAYLOR

THE USEFUL ARTS. No. VI.

SPICES AND OTHER CONDIMENTS.

in funeral ceremonies.

23

THE term spices is applied to certain vegetable products which are highly aromatic, or pungent, or both. In all mercial intercourse, of which we have any record, was ages, they have been much prized, and the earliest comchiefly carried on for the sake of these commodities. It was not solely as condiments to food that they were sought after; spices were extensively used in religious rites and CINNAMON is the bark of a species of Laurel (Laurus Cinnamomum) which grows in the south of the Indian Peninsula, but abundantly only in the Island of Ceylon, where it is extensively cultivated. Upwards of 400,000 pounds of this valuable produce are annually exported to Europe, and more than 25,000 persons, it is said, are engaged in Ceylon, either in the culture, or in the harvest. The tree attains a height of from twenty to thirty feet, with narrow leaves of a dark green on the upper, but lighter on the under side. It blossoms in January. The flowers are fragrant, white, resembling, in size and form, those of the Lilac; they are borne in clusters on long stalks springing from the axilla of the leaves. The fruit is a small berry, which becomes, when it is ripe, a thin shell containing a third or fourth year after it has been planted. These shoots single seed. The plant sends up numerous suckers the are cut when they become from half to three-quarters of an inch in diameter: the bark is stripped off and is freed from the outermost skin or epidermis; the wood is used only for fuel.

MACE and NUTMEG. The Nutmeg is the seed of the Myristica moschata, and Mace is a soft fleshy coat enveloping the seed; this coat is of a bright crimson colour, and as the fruit opens when it is ripe, the appearance of it on the tree is extremely pleasing. The plant is a native of the East Indian Archipelago; it is diœcious, and resembles the Laurel in its appearance. The seed has an outer skin of a black colour, which is easily detached, when the seed is quite dry; artificial heat is employed to accelerate this object, and to kill the vegetative power. The nutmeg yields, by pressure, an oil used in medicine.

CLOVES are the dried flower-buds of the Caryophyllus aromaticus, a large handsome tree of the myrtle tribe, and a native also of the East Indian Archipelago. They are beaten from the tree when the calix, or cup, expands, but before the petals open; the former organ is easily recognised in the spice, and the central round knob consists of the unexpanded petals, and not of the fruit, as is erroneously supposed. Upwards of 50,000 lbs. are annually consumed in Britain. Cloves yield abundance of essential oil, of a strong pungent aromatic flavour, to which that of the spice is due. This oil is extracted either from the fresh-gathered buds by pressure or by distillation: it is used in medicine.

ALLSPICE derives its name from its scent and flavour being supposed to embody those of several others, and for which it might be substituted. Allspice is the dried unripe berry of a tree, a species of myrtle, which is a native of both the East and West Indies. The plant is known by the name of Pimento, or Jamaica Pepper.

PEPPER is a generic name of several different produc-
tions. Black and White Pepper are the dried seeds,
ground to powder, of the Piper nigrum, a creeping plant
of the equinoctial regions of Asia and America. The two
spices only differ in the latter being blanched by soaking
in water, and having the black skin rubbed off; but a great
deal of White Pepper consists only of the inferior shrivelled
seeds, which, falling from the tree, have been blanched by
exposure to the air and sun. Long Pepper is only a variety
closer, and are imported whole.
of the common Pepper-tree, the racemes of the fruit being

of the Capsicum baccatum, or Bird-Pepper, a native of
CAYENNE PEPPER is made by grinding the dried fruit
both Indies. The fruit is a small fleshy capsule, of a bril-
from the pepper in question. There is a kind producing
liant scarlet, and of intense pungency, as every one knows
the strongest in its perfect state, and which forms an im-
very small species, known by the name of chilies, which is
portant ingredient in West India pickle. Though it is the
fruit which is used for making Cayenne pepper, yet the
seeds are equally, if not more, pungent.
The plant is

That is, a little after Midsummer, the country being in the
Southern hemisphere.

common in our green and hot-houses, and even in this climate the fruit is perfected, and is little inferior to that imported.

It should be mentioned, that though so powerful a stimulant, Cayenne pepper is considered more wholesome than the common black pepper.

GINGER is the woody root of the Zingiber officinalis, a native of south-eastern Asia and the adjoining islands, and long since cultivated in the West Indies. The plant is nearly allied to the arrow-root tribe, and somewhat resembles the Indian-shot.. The roots are sorted, washed, scraped, and dried in the sun. The young roots make an excellent preserve, and a great deal is imported in that state. Ginger is a valuable medicine, and is as wholesome as so powerful a stimulant can be.

MUSTARD is an infusion of the seeds ground to powaer of the Sinapis nigra, an indigenous plant, but also cultivated for the purpose. On the Continent it is usual to mix tarragon and several other herbs with mustard to flavour it; here it is generally only prepared with a little salt and water, and perhaps some vinegar. It is an extremely wholesome condiment, and is also a most valuable medicine; the whole seeds have lately been used as such, and an infusion of the powdered mustard in hot water is a speedy and safe emetic. It is also used when applied externally in the form of a plaster, to excite inflammation.

OILS are a most important class of vegetable, as well as animal, fluids. Vegetable oils are of two kinds,-fixed and volatile, easily distinguished by the following obvious characters: if a piece of paper be moistened with a fixed oil, it becomes more transparent, or what we call greasy, and never again loses that quality; whereas if a volatile oil be used in the same way, it dries up entirely after a time, leaving no trace behind it. The volatile oils are extremely numerous; it is to them that most parts of plants owe their aroma, fragrance, pungency, and other properties affecting the taste and smell.

Fixed oils are obtained principally from the seeds by pressure. The only one that we have to notice here is

OLIVE OIL. The Olive (Olea Europea) is extensively cultivated in the south of Europe, solely for the sake of the oil which is obtained from its fruit. This is a small green oval berry, containing a hard stone in which are two seeds. The frui must be gathered a little before it is quite ripe; the olives are spread on the floor of a room, and left for

THE OLIVE OIL MILL.

several days to dry and to ferment slightly: they are then crushed in a mill and the mass put into bags made of rushes or of coarse canvass, which being subjected to pressure in a screw press, the oil flows out and is received

into proper vessels, which are half filled with water, on the top of which the oil floats and is easily skimmed off. Where the process is carefully performed, the stone of the berry is not broken when the fruit is first put into the mill, the mill-stones being set wide enough apart to avoid doing so, and the oil first drawn off is of superior quality. After all this is expressed, the mass, stones and all, is either returned to the mill and the stones are broken, or the same effect is produced by mixing up the mass with boiling water and increasing the power of the press; by repeating this operation, not only a second, but even a third quality of oil is obtained.

The best oil is made in the neighbourhood of Aix, in France; that consumed in England is produced principally in Tuscany or the kingdom of Naples, though a great deal is also brought from Spain, and some from the Ionian islands. In our country, as an article of food, it is only a luxury used by the middling and upper classes, and the quantity consumed, therefore, is not great; about 5000 tons annually being the average, of which a considerable quantity is required in the woollen manufactures, and other arts; but in the countries which produce the olive, the oil constitutes a large proportion, in some way or other, of the food of the people, and is an absolute necessary. Olive oil is also employed to burn in lamps, an application of it which is forbidden by law in this country. To fit it for this latter use, the oil of the inferior quality is mingled with about a fiftieth part in weight of strong sulphuric acid, and water being added, the whole is well stirred together: in a few days a sediment of a charcoal settles to the bottom, and the oil is decanted off clear.

The refuse of olives, after all the oil is obtained from it, is given to hogs to fatten them, is burnt as fuel, or used as a manure. The unripe fruit is also pickled in salt-water flavoured with some spice, and is eaten after dinner by many persons in Britain, but much more abundantly on the Continent, to improve the flavour of certain wines.

In other countries, many other oils besides that of the olive are used for food; as for example, nut-oil, the oil of the filbert and of the beech; poppy-oil, rape-seed oil, oil of sesamum, and many others. Several of these are used in the arts in England, and will be subsequently noticed.

MUSTARD SEED." A grain of mustard seed" is said in the parable to be "the smallest of all seeds; but when it is grown up, it is the greatest among herbs, and becometh a tree, so that the birds of the air come and lodge in the branches thereof." The mustard of our own country is very far from answering this description: but there is in the East a species of sinapi, to which it, no doubt, alludes: it is called by Linnæus Sinapi crucoides. Its branches are real wood, as appears from a specimen once in the collection of Sir Joseph Banks. Lightfoot, Buxtorf, and others, quote the Jewish Rabbies to the same effect, whose testimony cannot be suspected of partiality to the New Testament. In the Talmud of Jerusalem it is said, "There was in Sichi a mustard-tree, which had three branches, one of which, being cut down, served to cover the hovel of a potter; and yielded three cabs of seed." The Rabbi Simeon says, "he had in his garden a shoot of the mustardtree, on which he climbed as if on a fig-tree." These statements are, at least, sufficient to show that we should not form a judgment of eastern herbs by those which are familiar among ourselves.

WISDOM and knowledge do not always go together There may be wisdom without knowledge, and knowledge without wisdom. A man without knowledge, if he walk humbly with his God, and live in charity with his neighbours, may be wise unto salvation. A man without wisdom may not find his knowledge avail him quite so well. But it is he who possesses both that is the true philosopher. The more he knows, the more he is desirous of knowing; and yet the farther he advances in knowledge, the better he understands how little he can attain, and the more deeply he feels that God alone can satisfy the infinite desires of an immortal soul. To understand this is the height and perfection of philosophy.-The Doctor.

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Sold by all Booksellers and Newsvenders in the Kingdom.

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UN DER THE DIRECTION OF THE COMMITTEE OF GENERAL LITERATURE AND EDUCATION APPOINTED BY THE SOCIETY FOR PROMOTING CHRISTIAN KNOWLEDGE.

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THE CATHEDRAL (OR MOORISH MOSQUE) AT CORDOVA, IN SPAIN.

CORDOVA.-II.

ITS CATHEDRAL, OR MOSQUE. We have already given a general account of the Spanish town of Cordova*, and spoke of the famous Mosque which was founded there by Abdurrahman, the first of the Western Caliphs, or independent Mohammedan rulers in Spain. This monarch did not live to complete his undertaking; a task which devolved upon his son and successor Hisham, who fulfilled it about the year 800. Subsequent Caliphs enlarged the edifice as the increase of population required, until it assumed the general form in which the Spaniards found it when they recovered the city from the Moors. In the estimation of the Mussul

mans, this mosque held the third rank, being deemed inferior in sanctity to the mosques of Jerusalem and Mecca alone; its size and splendour, according to their descriptions, certainly entitled it to be considered one of the most remarkable buildings in the world. The building was of a quadrangular form, 620 feet in length from north to south, and 440 in breadth from east to west; four streets surrounded it, and cut it off from all contact with other edifices. The roof was supported by 1200 or 1400 columns of the richest marbles, which formed nineteen aisles; the number of public doors was twenty-one, and all of

them were covered with the choicest Andalusian brass. The pulpit was formed of the most precious woods,— such as ebony, sandal, Brazil, citron-wood, wood of aloes, &c.; and its manufacture occupied a period of seven years. The door of the chief entrance, or that leading into what was called the Maksura, or sanctuary, was formed of gold, as was also the wall of the Mihrab, or chancel, which was sacred to the use of the Kiams, or priests; the floor of the Maksura was of pure silver, and here, on a throne of wood of aloes, with nails of gold, was preserved in a case of the same metal, set with pearls and rubies, the principal copy of the Koran. The tower of the mosque was seventy-two cubits in height; and its summit was crowned with three celebrated apples, two of pure gold, and the central one of silver,—each measuring three spans and a-half in circumference. Two hundred and eighty chandeliers of brass or silver, containing 7000 or 11000 lamps, illumined the interior of the building, and consumed annually 1100 pounds of cotton, and 27,000 pounds of oil; sixty pounds of wood of aloes, and as many of ambergris, were also required for perfumes.

The number of people employed in this mosque, such as priests, readers, wardens, door-keepers, proclaimers of the time of prayer, lighters of the lamps, and others, is said to have amounted to 300. A part of the quadrangle was, and is still, occupied by a court or garden, in which were performed the necessary ablutions before entering the mosque. It was surrounded on three sides by a portico supported by seventy-two columns; the water of three fountains, with the delightful shade afforded by many cypress, palm, and orange trees, maintained always a refreshing coolness in this enclosure.

After the conquest of Cordova by the Spaniards, in 1236, St. Ferdinand converted this mosque into a cathedral, and it preserved its ancient plan until the time of the Emperor Charles the Fifth. "In the year 1528," says Mr. Murphy, who has beautifully illustrated this noble edifice, in his splendid work on the Arabian antiquities of Spain, "the Spaniards began to disfigure its symmetry, by modern erections, which continued to be made in succeeding reigns, in order to convert it more effectually into a temple for * See Saturday Magazine, Vol. VI. p. 234.

celebrating the solemn rites of the Christian religion. In vain," he adds, "have remonstrances been made at different times by the lovers of the arts, nay, even by royalty itself, against these misplaced and tasteless alterations." The chief mutilation which is laid to the charge of the Chapter, is that occasioned by the erection of an immense choir which rises like a distant church in the centre of the quadrangle. "Were this in any other church," says Mr. Swinburne, "it would deserve great praise for the Gothic

grandeur of the plan, the loftiness of the dome, the

carving of the stalls, and the elegance and high finishing of the niches and ornaments; but, in the middle of the Moorish mosque, it destroys all unity of design, darkens the rest, and renders confused every idea of the original general effect of the building." The four fronts of this building present nothing but low walls of remarkable solidity, crowned with crenated or notched battlements, and supported at

intervals by buttresses, which, from a distance, have the appearance of towers. Each front differs from the rest both in height and in decorations; this arose from two causes,-the passionate fondness of the Arabs for variety, and the natural inequalities of the soil, which are even now (or were in Mr. Murphy's time) so great, that in order to reach the edifice it becomes necessary to ascend thirty steps on the south side, and on the north side to descend fourteen. In many of the compartments between the buttresses, horse-shoe arch, and ornamented with a fretwork of are placed doors, surmounted by the crescent or mosaic of baked earth; the brilliant colours with stucco, occasionally combined with a richly-variegated which these decorations are painted, must have produced a fine effect before any alterations were made in the building.

It is, however, the interior of this building which of A Year in Spain, "you find yourself in a forms its chief attraction; "Here" says the author perfect forest of columns, laid out in twenty-nine effect produced on entering. parallel rows." Travellers speak differently of the "Nothing" says one, singular, rather than beautiful edifice. I can imagine "can be more striking than the first step into this by the eye when placed in such spots of the church no coup d'œil more extraordinary than that taken in as afford a clear reach down the aisles, at right angles, uninterrupted by chapels and modern erections. Equally wonderful is the appearance when you look and arches in an oblique line. It is a most puzzling from the points that give you all the rows of pillars scene of confusion. Light is admitted by the doors and several small cupolas; but, nevertheless, the church is dark and awful; people walking through this chaos of spirits seem to answer the romantic ideas of magic, enchanted knights, or discontented curious but not beautiful or striking, the chief interest wandering spirits." Mr. Inglis says that the view is arising from the knowledge we at once obtain from it of the structure and interior of a mosque; divested of this interest, he says, it is a labyrinth of small speaks of the mosque generally, as "even in its pillars without order or elegance. Captain S. S. Cook Europe; the effect on entering," he says, “the inaltered state the greatest architectural curiosity in tersection of twenty-nine rows of columns with nineteen others,—the dim light, just sufficient to shadow the distance, the strange effect of these colonnades height of only 30, cannot be described, and stands over an extent of 600 feet by 400, and with the unequalled."

About three miles from Cordova once stood the famous palace or city of Azzahra, or Zehra, which

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