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Mindanao is not excessively hot, though it lies within six degrees of the equator, as it is refreshed by the sea-breezes on every side in the day-time. The middle of the country is woody and mountainous: but between the hills are rich valleys, and near the sea-coast the country is generally flat. It produces rice,and such fruits as grow between the tropics. They have also libby or sago trees; of the pith of which they make bread. Great quantities of it are exported, after it is dried and drained like seed. The plantain wood is beautiful here, and in great perfection. It is their principal food, and they also make their drink of it. In the reign of Philip II. king of Spain, Don Lewis de Velasco, viceroy of Mexico, sent Michael Lopez de la Gaspes, with a fleet and force sufficient to make a conquest of these islands, which he afterwards named the Philippines, in honour of the above monarch.

The city of Magindanao is situated on the south-east side of the island, has a river capable of admitting small vessels, and carries on a considerable trade with Manilla, Sooloo, Borneo, and the Moluccas. Their exports are rice, tobacco, bees-wax, and spices; in return for which they receive coarse cloths of Coromandel, China-ware, and opium. The village or town of Samboingan is situated on the banks of a small rivulet, which empties itself immediately into the sea, and is agreeably shaded by proves of cocoa trees. The number of its inhabitants are about 1000, among which are included the officers, soldiers, and their respective families. In its environs there are several small look out houses, erected on posts of twelve feet high, in all of which a constant guard is kept; so that it appears as if the Spaniards were in a continual state of enmity with the natives, The houses are built of those simple materials which are of very general use in the eastern seas. They are erected on posts, and built of bamboo, covered with mats; the lower apartments serve for their hogs, cattle, and poultry, and the upper ones are occupied by the family. Lon. 125. 0 W. Lat. 6. Ο Ν.

MINDED. a. (from mind.) Disposed; inclined; affected (Tillotson).

MINDELHEIM, a town of Suabia, with a castle. It is the capital of a small territory between the rivers Iller and Lech, subject to the house of Bavaria. It was taken by the Austrians, after the battle of Blenheim, who erected it into a principality in favour of the duke of Marlborough; but it returned to the house of Bavaria, by the treaty of Rastadt. It is 30 miles S.E. of Ulm. Lon. 10. 42 E. Lat. 48.3 N.

MINDEN, a town of Westphalia, capital of a territory of the seme name. Near this town prince Ferdinand of Brunswick defeated the French in 1759. It is subject to the king of Prussia, and is seated on the Weser; 27 miles E. by S. of Osnaburg, and 37 W. of Hanover. Lon. 9. 5 E. Lat. 52.

22 N.

MI'NDFUL. a. (mind and full.) Attentive; heedful; having memory (Hammond). MINDFULLY.ad. Attentively; heedfully. MINDFULNESS. s. Attention; regard. MINDLESS. a. (from mind.) 1. Inatten tive; regardless (Prior). 2. Not endued with a mind; having no intellectual powers (Davies). 3. Stupid; unthinking (Shakspeare). MIND-STRICKEN.a. (mind and stricken). Moved; affected in his mind (Sidney).

MINDORO, one of the Philippine Islands, 50 miles in circumference, separated from Luconia by a narrow channel. It is full of mountains, which abound in palin-trees, and all sorts of fruit. The inhabitants are pagans, and pay tribute to the Spaniards.

MINE, in natural history, a deep pit under ground, from whence various kinds of minerals are dug out; but the term is more particularly applied to those which yield metals. Where stones only are procured, the appellation of quarries is universally bestowed upon the places from which they are dug out, however deep they may be.

Ás, therefore, the matter dug out of mines is various, the mines themselves acquire various denominations, as gold-mines, silver-mines, copper-mines, iron-mines, diamond-mines, salt-mines, mines of antimony, of alum, &c.

Mines, then, in general, are veins or cavities within the earth, whose sides receding from, or approaching nearer to each other, make them of uneqnal breadths in different places, sometimes forming larger spaces, which are called hules: they are filled with substances, which, whether metallic or of any other nature, are called the loads; when the substances forming these loads are reducible to metal, the loads are by the miners said to be alive; otherwise they are called dead loads. In Cornwall and Devon, the loads always hold their course from eastward to westward; though in other parts of England, they frequently run from north to south. The miners report, that the sides of the load never bear in a perpendicular, but constantly underlay, either to the north or to the south. The load is frequently intercepted by the crossing of a vein of earth, or stone, or some different mictallic substance; in which case it generally happens that part of the load is moved a considerable distance to the one side. This transient load is by the miners called flooking: and the part of the load which is to be moved is said to be heaved. According to Dr. Nichols's observations upon mines, they seem to be, or to have been, the channels through which the waters pass within the earth, and, like rivers, have their small branches opening into them, in all directions. Most mines have streams of water running through them; and when they are found dry, it seems to be owing to the waters having changed their course, as being obliged to it, either because the load has stopped up the ancient passages, or that some new and more easy ones are made. Mines, says Dr. Shaw, are liable to many contingencies; being sometimes poor, sometimes soon exhaustible, sometimes subject to be drowned, especially

when deep, and sometimes hard to trace; yet there are many instances of mines proving highly advantageous for hundreds of years: the mines of Potosi are to this day worked with nearly the same success as at first; the goldmines of Cremnitz have been worked for thousands of years; and our Cornish tinmines are extremely ancient. The neat profit of the silver alone, dug in the Misnian silvermines in Saxony, is still, in the space of eight years, computed at a thousand six hundred and forty-four millions, besides seventy-three tons of gold. Many mines have been discovered by accident: a torrent first laid open a rich vein of the silver-mine at Friberg in Germany; sometimes a violent wind, by blowing up trees, or overturning the parts of rocks, has discovered a mine; the same has happened by violent showers, earthquakes, thunder, the firing of woods, or even the stroke of a plough-share, or horse's hoof.

But the art of mining does not wait for these favourable accidents, but directly goes upon the search and discovery of such mineral veins, ores, or sands, as may be worth the working for metal. The principal investigation and discovery of mines depend upon a particular sagacity, or acquired habit of judging from particular signs, that metallic matters are contained in certain parts of the earth not far below its surface. The principal signs of a latent metallic vein seem reducible to general heads, such as, 1. The discovery of certain mineral waters. 2. The discoloration of the trees or grass of a place. 3. The finding of pieces of ore on the surface of the ground. 4. The rise of warm exhalations. 5. The finding of metal lic sands, and the like. All which are so many encouragements for making a stricter search near the places where any thing of this kind appears; whence rules of practice might be formed for reducing this art to a greater certainty. But when no evident mark of a mine appears, the skilful mineralist usually bores into the earth, in such places as from some analogy of knowledge, gained by experience, or by observing the situation, course, or nature of other mines, he judges may contain metal.

After the mine is found, the next thing to be considered is whether it may be dug to advantage. In order to determine this, we are duly to weigh the nature of the place, and its situation, as to wood, water, carriage, healthiness, and the like, and compare the result with the richness of the ore, the charge of digging, stamping, washing, and smelting.

Particularly the form and situation of the spot should be well considered. A mine must either happen, 1. In a mountain. 2. In a hill. 3. In a valley. Or, 4. In a flat. But mountains and bills are dug with much greater ease and convenience, chiefly because the drains and burrows, that is, the adits or avenues, may be more readily cut, both to drain the water and to form gangways for bringing out the lead, &c. In all the four cases we are to look out for the veins which the rains, or other accidental thing, may have laid bare; and if such a vein be found,

it may often be proper to open the mine at that place, especially if the vein prove tolerably large and rich: otherwise the most commodious place for situation is to be chosen for the purpose, viz. neither on a flat, nor on the tops of mountains, but on the sides. The best situation for a mine is a mountainous, woody, wholesome spot; of a safe easy ascent, and bordering on a navigable river. The places abounding with mines are generally healthy, as standing high, and every where exposed to the air; yet some places, where mines are found, prove poisonous, and can upon no account be dug, though ever so rich: the way of examining a suspected place of this kind, is to make experiments upon brutes, by exposing them to the effluvia or exhalations, to find the effect. (British Ency.)

MINE, in military affairs, is also a subterraneous cavity made according to the rules of art, in which a certain quantity of powder is lodged, which by its explosion blows up the earth above it.

It has been found by experiment that the figure produced by the explosion is a paraboloid; and that the centre of the powder, or charge, occupies the focus.

The place where the powder is lodged is cailed the chamber of the mine, or forneau. The passage leading to the powder is called the gallery.

The line drawn from the centre of the chamber, perpendicular to the nearest surface of the ground, is called the line of least resistance.

The pit or hole, made by springing the mine, is called the excavation.

The fire is communicated to the mine by a pipe or hose, made of coarse cloth, whose diameter is about one inch and a half, called a saucisson (for the filling of which near half a pound of powder is allowed to every foot), extending from the chamber to the entrance of the gallery; to the end of which is fixed a match, that the miner who sets fire to it may have time to retire before it reaches the chaniber.

To prevent the powder from contracting any dampness, the saucisson is laid in a small trough, called an auget, made of boards, three inches and a half broad, joined together lengthwise, with straw in it, and round the saucisson, with a wooden cover nailed upon it.

Galleries and chambers of mines.-Galleries made within the fortification, before the place is attacked, and from which several branches are carried to different places, are generally four feet or four and a half wide, and five feet or five and a half high. The earth is supported from falling in by arches and walls, if they are to remain for a considerable time; but when mines are made to be used in a short time, then the galleries are but three feet or three and a half wide, and five feet high, and the earth is supported by wooden frames or props.

The gallery being carried on to the place where the powder is to be lodged, the miners make the chamber. This is generally of a cubical form, large enough to hold the wooden box, which contains the powder necessary for the

charge: the box is lined with straw and sandbags, to prevent the powder from contracting dampness.

The chamber is sunk something lower than the gallery, if the soil permits: but where water is to be apprehended, it must be made higher than the gallery; otherwise the besieged will let in the water, and spoil the mine. Quantities of powder to charge mines.-Before any calculation can be made of the proper charge for a mine, the density and tenacity of the soil in which it is to be made must be ascertained, either by experiment, or otherwise; for in soils of the same density, that which has the greatest tenacity will require the greatest force to separate its parts. The density is determined by weighing a cubic foot (or any certain quantity) of the soil; but the tenacity can only be determined by making a mine. The following table contains experiments in six different soils, which may be of some assistance to form a judgment of the nature of the soil, when an actual experiment cannot be had:

Nature of the soil.

Density. Tenacity.

rammed in the strongest manner: the least neglect in this work will considerably alter the effect of the mine.

The auget is then laid from the chamber to the entrance of the gallery, with some straw at the bottom; and the saucisson laid in it, with straw over it: lastly, it must be shut with a wooden cover nailed upon it. Great care must be taken, in stopping up the gallery, not to press too hard upon the auget, for fear of spoiling the saucisson; which may hinder the powder from taking fire, and so prevent the mine from springing. The gallery is stopped up with stones, earth, and dung, well rammed, six or seven feet further from the chamber than the length of the line of least resistance.

MINE. pronoun possessive. (mýn, Saxon.) Belonging to me (Dryden).

To MINE. v. n. (from the noun.) To dig mines or burrows (Woodward).

To MINE. v. a. To sap; to ruin by mines; to destroy by slow degrees (Shakspeare).

MINEHEAD, a borough in Somersetshire, with a market on Wednesday. It has a good harbour on the Bristol channel, for ships of large burden; and carries on a trade in wool, Weight of Quantity of coal, and herrings. It sends two members to parliament, and is 31 miles N. of Exeter, and 161 W. by S. of London. Lon. 3. 34 W. Lat. 51. 12 N.

one cubic

powder to raise one cubicfathom.

8 pás.

foot.

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10

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Loading and stopping of mines.-The gallery and chamber being ready to be loaded, a strong box of wood is made of the size and figure of the chamber, being about one-third or onefourth bigger than is required for containing the necessary quantity of powder: against the sides and bottom of the box is put some straw; and this straw is covered over with empty sandbags, to prevent the powder from contracting any dampness: a hole is made in the side next the gallery, near the bottom, for the saucisson to pass through; which is fixed to the middle of the bottom, by means of a wooden peg, to prevent its loosening from the powder; or that, if the enemy should get to the entrance, he may not be able to tear it out. This done, the powder is brought in sand-bags, and thrown loose in the box, and covered also with straw and sand-bags; upon this is put the cover of the box, pressed down very tight with strong props; and, to render them more secure, planks are also put above them, against the earth, and wedged in as fast as possible.

This done, the vacant spaces between the props are filled up with stones and dung, and

MINEIDES, the daughters of Minyas or Mineus, king of Orchomenos, in Boeotia. They were three in number, Leuconoe, Leucippe, and Alcithoe. Ovid calls the two first Clymene and Iris. They derided the orgies of Bacchus, for which impiety the god inspired them with an unconquerable desire of eating human flesh. They drew lots which of them should give up her son as food to the rest. The lot fell upon Leucippe, and she gave up her son Hippasus, who was instantly devoured by the three sisters. They were changed into bats.

MINER. s. (mineur, French.) 1. One who digs for metals (Dryden). 2. One who makes military mines (Tatler).

MINERAL, in natural history, is used in general for all fossile bodies, whether simple or compound, dug out of a mine; from whence it takes its denomination.

MINERAL CAOUTCHOUC: a species of BITUMEN, which see.

MINERAL MUMMY. Mineral pitch. A species of BITUMEN, which see. MINERAL TALLOW: a species of BITUMEN, which see. a species of BITUMEN,

MINERAL TAR: which see.

MINERAL WATERS, (Aquæ minerales. Aqua medicinales.) Waters holding minerals in solution. But as all water, in a natural state, is impregnated, either more or less, with some mineral substances, such waters as

the name mineral waters should be confined to mineral matters to produce some sensible effects on are sufficiently impregnated with the animal economy, and either to cure or prevent some of the diseases to which the human body is liable. On this account, these waters might be with much more propriety called medicinal waters

were not the name by which they are commonly known too firmly established by long use.

The first knowledge of mineral waters, like every ether branch of knowledge we possess, was accidentally discovered. The good effects they produced on such as used them, have doubtless been the cause of distinguishing them from common waters. The first philosophers who considered their properties attended only to their sensible qualities, such as colour, weight, or lightuess, smell, and taste. Pliny, however, distinguished a great number of waters, either by their physical properties or their uses; but the inquiry after methods of ascertaining, by chemical processes, the quantity and quality of the principles held in solution by mineral waters, was not attempted till the seventeenth century. Boyle is one of the first who, in the valuable experiments on colours published by him at Oxford in 1663, mentioned several re-agents capable of indicating the substances dissolved in water, by the alteration produced in their colours. The academy of sciences, from its first institution, was aware of the importance of analysing mineral waters; and Duclos, in 1667, attempted the examination of the mineral waters of France: the researches of this chemist may be found in the original memoirs of this society. Boyle was particularly employed in inquiries respecting mineral waters about the end of the seventeenth century, and published a treatise on this subject in 1685. Boulduc, in the year 1729, published a method of analysing waters, which is much more perfect than any which were employed before his time: it consists in evaporating these fluids at different times, and separating by filtration the substances which are deposited, in proportion as the evaporation proceeds.

Many celebrated chemists have since made successful experiments on mineral waters, and almost every one made valuable discoveries respecting the different principles contained in these fluids. Bouldoc discovered natron, and determined its properties: Le Roi, physician of Montpellier, discovered calcareous muriat; Margraaff, the muriat of magnesia; Priestley, carbonic acid; and Monnet and Bergman the sulphurated or hepatic hydrogen gas. The two last-mentioned chemists, besides the discoveries with which they have enriched the art of analysing waters, have published complete treatises on the method of proceeding in this analysis; and have carried this part of chemistry to a degree of perfection and accuracy far exceeding that which it possessed before the time of their labours. We are likewise in possession of particular analyses, made by very good chemists, of a great number of mineral waters, and which serve to throw great light on this inquiry, which, with justice, is esteemed one of the most difficult in the whole art of chemistry. The limits here prescribed do not permit us to enter at large into the history of the analyses of waters, which may be found in many treatises, one of the best of which is that published a few years since by Dr. Saunders.

Principles contained in Mineral Waters.—It is but a few years since the substances capable of remaining in solution in water have been accurately known. This appears to have arisen from the want of accurate chemical methods of ascertaining the nature of these substances: and the certainty of their existence has naturally followed the discovery of methods of ascertaining them. Another cause which has retarded the progress of science in this respect is, that mineral matters dissolved in waters are almost al ways in very sinall doses, and are also mixed together in considerable numbers, so that they mutu

ally tend to conceal or alter those properties in which their distinctive characters consist. Nevertheless, the numerous experiments of the chemists before quoted, and a great number of others, which we shall occasionally mention, have shown, that some inineral substances are often found in waters, others scarcely ever met with; and lastly, many which are never held in solution by that fluid. We shall here consider each class of these substances in order.

Siliceous earth is sometimes suspended in waters; and as it is in a state of extreme division, it remains suspended without precipitating; but its quantity is extremely minute. The carbonated alkalis and chalk probably contribute to render siliceous earth soluble.

The

Alumine likewise appears to exist in water. extreme subtlety of this earth, by which it is dispersed through the whole mass of water, causes it to render them turbid. Argillaceous waters are therefore whitish, and have a pearl or opal colour; they are likewise smooth, or greasy to the touch, and have been called saponaceous waters. Carbonic acid seems favourable to the suspension and solution of alumine in water.

Lime, magnesia, and barytes, are never found pure in waters; they are always combined with acids.

Fixed alkalis are never met with in a state of purity in waters, but frequently combined with acids, in the form of neutral salts.

The same observation applies to ammoniac, and most acids, except the carbonic acid, which is often free, and in possession of all its properties in waters. It constitutes a peculiar class of mineral waters, known by the name of gaseous, spirituous, or acidulous waters.

Among the neutral salts, with bases of fixed alkalis, scarcely any are met with but sulphat of soda or Glauber's salt, the muriats of soda and of potash, and carbonat of soda, which are frequently dissolved in mineral waters; nitrat and carbonat of potash are rarely found.

Sulphat of lime, calcareous muriat, chalk, sulphat of magnesia, or Epsom salt, muriat of magnesia, and carbonat of magnesia, are the earthy salts which are most commonly found in waters. As to the calcareous nitrat of magnesia, which some chemists have asserted they have met with, these salts are scarcely ever found in mineral waters properly so called, though they exist in salt waters.

The aluminous neutral salts, and salts with base of barytes, are scarcely ever dissolved in waters. Alum or acid sulphat of alumine appears to exist in some waters.

Pure hydrogen gas has not yet been found dissolved in mineral waters.

Pure sulphur has not yet been found in these fluids, though it exists very rarely in small quantities in the state of sulphuret of soda. Sulphureous waters are most commonly mineralized by sulphurated hydrogen gas.

Lastly, Among metals, iron is most commonly dissolved in water, and may be found in two states; either combined with carbonic acid, or with the sulphuric acid. Some chemists have supposed that it was likewise dissolved in its metallic state, without an acid intermedium: but as this metal scarcely ever exists in nature without being in the state of oxyd, combined with the carbonic or sulphuric acid, the opinion of these philosophers could only be maintained at the time when the carbonic acid was not yet discovered: and the solution of iron in water, without the assistance of the sulphuric

acid, could not otherwise be accounted for. Berg man affirms, that iron, as well as manganese, is found in certain waters, combined with the muriatic acid.

Oxyd of arsenic, and the sulphats of copper and zinc, which exist in many waters. communicate poisonous properties to them, and show, when discovered by analysis, that the use of such waters must be carefully avoided.

Most chemists at present deny the existence of bitumen in waters: in fact, the bitter taste was the cause why waters were formerly supposed to contain this oily substance; but it is now known that this taste, which does not exist in bitumen, is produced by the calcareous muriat.

There is no difficulty in conceiving how water, which percolates through the interior parts of the globe, and especially through the mountains, may become charged with the different substances we have enumerated. It is likewise clear, that according to the nature and extent of the strata of earth, through which they pass, mineral waters will be more or less charged with these principles, and that the quantity and nature of these principles must be subject to great variations, especially when we consider the changes in the direction of their course to which these fluids are liable from the various alterations which the globe undergoes, particularly on its surface and its more elevated parts.

Classes of Mineral Waters.-It appears from what we have already observed respecting the different substances usually contained in mineral waters, that these fluids may be classed according to the earthy, saline, and metallic substances they hold in solution; and that the number of classes, on this principle, would be very considerable: but it must be observed, that none of these substances are found single and alone in waters: but, on the contrary, they are often dissolved in the number of three, four, five, or even more. This circumstance creates a difficulty in the methodical classification of waters, relative to the principles that they contain. However, if we attend to those substances which are the most abundantly contained in waters, or whose properties are the most prevalent, we shall be able to make a distinction, which, though not very accurate, will be sufficient to arrange these fluids, and to form a judgment of their virtues. Chemists who have attended to mineral waters in general have availed themselves of this method. Monnet has established three classes of mineral waters; the alkaline, the sulphureous, and the ferruginous; and subsequent discoveries have enlarged the number of classes. Duchanoy, who has published a valuable treatise on the art of imitating mineral waters, distinguishes ten, viz. the gaseous, the alkaline, the earthy, the ferruginous, the simple hot, the gaseous thermal, the saponaceous, the sulphureous, the bituminous, and the saline waters. Although it may be urged as a reproach, that this author has made his classes too numerous, since the pure gaseous and bitu minous waters are unknown; yet his division is doubtless the most complete, and gives the most accurate idea of the nature of the different mineral waters, and consequently is the best suited to his subject. We shall here propose a division less extensive, and in our opinion more methodical, than that of Duchauoy; at the same time observing, that we do not consider simple thermal waters as mineral waters, because they consist merely of heated water, according to the best chemists; and

1

that we shall not speak of bituminous waters, because none such have been yet found.

It appears to us, that all mineral waters may be arranged in four classes, viz. acidulous, saline, sulphureous, and ferruginous waters.

CLASS I.-Acidulous Waters.

Gaseous waters, which may with more propriety be called acidulous waters, are those in which the carbonic acid predominates; they are known by their sharp taste, and the facility with which they boil and afford bubbles by simple agitation: they redden the tincture of turnsole, precipitate lime water and alkaline sulphures. As no waters have yet been discovered which contain this acid pure and alone, we think this class may be divided into several orders, according to the other principles contained in them, or the modifications they exhibit. They all appear to contain more or less alkali and calcareous earth; but their different degrees of heat afford a good criterion for dividing them into two orders: the first might comprehend cold, acidulous, and alkaline waters, such as those of Seltzer, Saint-Myon, Bard, Langeac, Chateldon, Vals, &c. in the second might be placed hot, or thermal, acidulous, and alkaline waters, as those of Mount D'Or, Vichy, Chatelguyou, &c.

CLASS II.-Saline or Salt Waters.

By the name of saline waters, we understand such as contain a sufficient quantity of neutral salt to act strongly on the animal economy, so as most commonly to purge. The theory and nature of these waters are easily discovered; they perfectly resemble the solutions of salt made in our laboratories; but they almost always contain two or three different species of salts. The sulphat of soda is very rare; sulphat of magnesia, or Epsom salt, inarine salt, or muriat of soda, calcareous and magnesian muriats, or the saline principles which mi neralized them, either together or separate. The waters of Sedliz, of Seydschutz, and of Egra, abound with Epsom salt, frequently mixed with muriat. of Those of Balaruc contain magnesia. muriat of soda, chalk, and the calcareous and magnesian muriats; those of Bourbonne, muriat of soda, sulphat of lime and chalk; and those of la Mothe contain muriat of soda, sulphat of lime chalk, sulphat of magnesia, muriat of magnesia and an extractive matter. It must be here ob served, that salts, with base of magnesia, are much more common in waters than has hitherto been supposed; and that few analyses have yet been made in which they have been well distinguished from calcareous muriat.

CLASS III.-Sulphureous Waters.

The name of sulphureous waters has been given to such mineral waters as appear to possess some of the properties of sulphur; such as the smell, and the property of discolouring silver. Chemists have long been ignorant of the true mineralizer of these waters; most have supposed it to be sulphur, but they never succeeded in exhibiting it, or at least have found it in quantities scarcely perceptible. Those who have made experiments on some of these waters have allowed them to contain either sulphureous spirit, or an alkaline sulphur. Venel and Monnet are the first who opposed this opinion; the latter, in particular, nearly discovered the truth, when he considered sulphureous waters as impregnated merely by the vapour of

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