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being taken of the proper diameter, its edge is sharpened by a few rubs of the file, and pressed against the cork under continuous rotatory motion, when it soon penetrates through the central core, escaping through the tube itself. As there is some little chance, however, that the side of the cork where the hole emerges may assume a ragged aspect, it is better to commence the operation at one end of the cork, then without penetrating quite through withdraw the borer, and recommence at the other end, thus causing the operation to terminate in the middle. If the aperture be clean and smooth it may be considered finished; if it be rugged and uneven, however, it will require trimming with the rat's-tail file. The aperture being made, we now come to the insertion of the tobacco-pipe shank, a matter of much simplicity ; one would think that no special instructions were necessary. It is not so :-the operation requires to be set about in a systematic way ; and although in this case, the operator might succeed after many attempts, and tobacco-pipes being cheap enough, these numerous attempts might be made without the objection of great expense; yet considering the necessity for performing similar operations under modified circumstances to which the objection of expense and many others would strongly apply, it is better to cultivate the right habit at once. Temember, then, tobacco-pipes and glass tubes are not like metal rods. We cannot fit them tightly, by violently twisting, turning, and pushing, nevertheless we must fit them air-tight. Our object is accomplished by easing them in, to use a popular but an expressive word. Their accuracy of adjustment is secured by paying attention to various little circumstances of detail. If, then, the end of the tobacco-pupe shank be ragged, as it most likely will be, rub off those ragged inequalities by means of a file. Had we been concerned with a thin glass tube instead of a tobacco-pipe, the better plan of treatment would have consisted in melting the extreme end of the same by holding it for a few instants in the flame of a spirit-lamp or a jet of gaS.

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Our present operations having reference to clay, not glass, we have not this resource; but on the other hand a tobaccopipe shank is stronger than a glass tube, in consideration of which I have chosen it, otherwise a piece of glass tube would have answered the purpose equally well. Having finished the attachment of the tobacco-pipe shank, we now come to the attachment of the cork itself, which is effected by accurate filing, a slightly conical form being imparted to the cork, in order that it may tightly fit with the minimum of pressure. This precaution is especially requisite when a thin necked flask has to be corked. In this ease a very slight amount of pressure will infallibly break the neck Jf the flask. * The cork I will now assume to have been accurately adapted, by filing, to its orifice; but it is hard and rigid. Corks may be softened by immersion in bouling water, a treatment which will answer all present ends; but cases frequently present themselves when a cork, forming part of a chemical apparatus, must be absolutely dry, under which circumstances it must be softened by immersion in hot sand, or more extemporaneously, but less rapidly, by holding it for a few seconds in the flame of a spirit-lamp. Having completed the arrangements to the extent described,

it remains to attach the length of India-rubber tubing to the tobacco-pipe shank, and a few inches of glass tubing to that or India-rubber, so that eventually an apparatus may result of the following shape, where a represents the point of attachment between the India-rubber tube, and tobacco-pipe shank; and

Fig. 4.

as the point of attachment between the latter, and the associated. glass tube.* Perhaps it is scarcely necessary to indicate that round or oval glass flasks will not stand upright without some kind of support; they may require to be supported whilst exposed to heat or after removal from heat. In the former case rings or triangles are usually employed, attached to a vertical stand, and capable of elevation or depression (fig. 5). Instruments of this kind can be procured ready made, but every experimenter possessed of moderate ingenuity can prepare them. or their substitutes for himself. A carpet-rod, around oneextremity of which has been cast a block of lead, answers perfectly, and the rings may be made of stout iron wire, as represented in fig. 6.

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in the brain or take flight just as best suits its own good pleasure, it sticks there all the firiner. I always give collateral facts an option of this kind. To effect the union of sulphur with iron, in other words, to make sulphuret of iron, it is Imerely necessary to bring a white-hot bar of iron in contact with a roll of sulphur; then the iron drops into melted globules which seem like iron itself, but which in reality are a ‘compound of iron and sulphur, and weigh heavier than the iron by the weight of the sulphur where with they have combined. The greater number of metals can be made to combine with -sulphur, by a similar treatment to that now described, and, indeed, perhaps the act or combination just effected may have 'presented itself to the reader's attention under the aspect of natural magic. To melt a mail in a walnut-shell, is a proposition often constituting the subject of a wager. The learner now sees ‘how that wager might be won. A nail being heated to whiteness, is dropped into a walnut-shell containing sulphur, when the fusion of the nail immediately takes place.

Let the sulphuret of iron thus resulting be transferred to a bottle labelled Sulphuret of Iron, and put away,+we shall require it presently. We will now return to the zinc solution, which has been so long neglected that the student may fear the original subject of the lesson has been forgotten. Not so. Tvery point expatiated on, everything done, has had reference to the metal zinc.

I have already said that the metallic zinc employed remains in the solution; the next point, then, is to ascertain the conditions it has assumed, and this information may be obtained by driving off the liquid in which it is dissolved. This is accomplished by the application of heat, which, causing the liquid to become steam or vapour, the latter is driven off, and all bodies contained in the liquid, not capable of assuming this vaporous condition, necessarily remain.

The application of heat in many processes of evaporation and distillation requires many precautions. For the most part naked fires are ineligible; frequently a sand-bath is the best means of applying heat, and it is the source of heat we shall employ now, fig. 7; but occasionally the heat capable of being imparted by sand would be injuriously high, hence

a proper substitute must be found to take its place, and hence the terms water-bath, oil-bath, &c.

Fig. 7.

A sand-bath consists of an iron dish (a saucepan answers very well) containing sand, and hung or rested over any convenient source of heat. A few pieces of lighted charcoal supply a very convenient source of heat; and by putting the lighted charcoal into a perforated earthenware flower-pot, strengthened by banding with copper or iron wire, we gain all the advantages of a furnace ; a temporary grating may readily be made of strong wire, and the pots, pans, and other vessels to be heated may be supported on triangles of hoop iron, fig. 8.

Fig. 8.

The preceding diagram represents a furnace of this kind, which may be worked on a table, the latter being protected from heat by the intervention of a Welch tile or flat stone. Probably the furnace will crack, owing to the intense heat within. It is, however, none the worse for this accident— the binding wires prevent all separation between the various pieces of which the furnace is composed; and, in short, the furnace is no less useful than before.

Supposing the solution of zinc in oil of vitriol and water to be placed in a saucer or porcelain dish, specially made for the purpose, under the name of evaporating dish ; supposing the solution and its dish to be embedded in the sand-bath, and the latter placed on its hoop-iron tripod over a fire, heat will rapidly penetrate the sand, and evaporation will ensue. If the solution were to be evaporated very slowly, the saucer or pan would eventually contain white crystals. If, however, the evaporation be more rapidly pushed, then crystals do not appear, but a white confused mass. I suppose the latter to be the case. As soon as evaporation is complete, and the residue has become thoroughly dry, remove the saucer from the sand-bath, allow it to cool, and when cold dissolve the evaporated material in distilled water. The liquid now returns to the state in which it originally was before evaporation, with this difference, any excess of oil of vitriol over and above the quantity necessary to dissolve the zinc, has been driven away

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by evaporation Pour the solution now into a wine-glass, and proceed as follows:– Into the Florence flask put about half an ounce of the sulphuret of iron, broken small (about the size of peas); add a mixture of six parts by measure of water, and one part by measure of oil of vitriol: quickly replace the cork of the Florence flask, and dip the end of the glass tube into the Vessel containing the zinc solution. From the contents of the Florence flask a very offensive, but at the same time a very useful gas will pass;–it is called sulphuretted hydrogen, or hydro-sulphuric acid. The general disposition of the apparatus is represented in the accompanying wood-cut, fig. 9.

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Observe now the result. The zinc solution immediately deposits a white powder, and no other metal, except zine, would, &nder the conditions of our experiment, have deposited a white zowder. Thus arises a most important addition to our knowiedge concerning zinc.. To obtain this white powder, which is called sulphuret of zinc, being a compound of sulphur and zinc,--to obtain this white compound, I say, is the object to which all our care and attention have been directed—all our cork-boring, and furnace-making energies, brought into play.

Perhaps some chemical beginner may think the result, hardly justifies the trouble with which it has been achieved. Not so ; the result is all important, as will soon be perceived. One instance of its importance, slightly anticipating another part of our subject, I will now give. o

Zinc is readily thrown down out of its solution in oil of vitriol and water, by transmitting through it a current of sulphuretted hydrogen gas, as we have seen. Most other metals are also capable of being thrown down by this gas, but iron is one of a few exceptions. Hence, supposing iron and zinc had both been dissolved in oil of vitriol and water, and the proposition had been to separate the iron from the zinc, this might readily have been effected by pouring through the mixed solution a stream of sulphuretted hydrogen gas, which would have thrown down the zinc, but left the iron.

We have not quite left the zinc yet. We shall return to it hereafter; meantime, let the wine-glass be labelled “Sul2huret of Zine,” covered with a pane of glass to protect it from dust, and set aside, fig. 10.

The student will have noticed that the sulphuretted hydrogen, or hydro-sulphuric acid gas, by which the throwing down

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Pour into the four-ounce phial cold distilled water, until the vessel is about two-thirds full, then cause the gas to pass through it in bubbles—the operator agitating the bottle frequently, fig. 11. Continue the operation until the water refuses. to dissolve any further portion of gas, which may be known by removing the bottle from the table on which it stands; grasp it firmly, pressing the thumb against its mouth ; agitate briskly. If the water be not yet satisfied, it will endeavour to suck in the thumb, fig. 12. Give it, therefore, more gas, and when . fully charged, label it thus—“Hydro-sulphuric Acid Solution,” and set it aside, fig. 13.

L ES SONS IN ENGLISH.—No. LXVII. Tły John R. BEARD, D.D.

AGREEMENT OF THE SUBJECT AND VERB.

WHILE the subject of a proposition may agree with a qualifying . adjective and a limiting or defining article, it specially agrees with the verb. The agreement is of two kinds, one of form, another of substance; one flexional, another logical. We may express these facts differently, by saying that if the verb is in the plural number, its subject must be in the plural number; and if the subject is in the plural number, in the plural number must the verb be. In other words, both subject and verb take the same condition; and this is what I mean by stating that the subject and the verb must agree. Avoid, therefore, the error common with uneducated people, of joining together subjects and verbs of different numbers. This error most commonly consists in omitting the s where it should be placed, namely, in the third person singular, and putting the s where it should not be placed, namely, in the third person plural. I subjoin the present tense

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In the third person singular and plural, nouns may take the place of pronouns; thus, we say, Pronouns: he drinks they drink they drink Nouns: the man drinks the men drink the women drink The sulject and the verb then must be in the same person. Now the only person that ends in s is the third person; consequently, an s put to the verb in any other person is an ungrammatical addition. In general, then, the rule is this:– The subject and the verb must be in the same number and person; or, to state the same fact differently, the subjects and their verb must agree in number and person. Nouns of multitude, i.e., nouns signifying many, take their verbs

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Let me distinctly state that two or more nouns, or a noun and a pronoun, are said to be in apposition, when, being in the same number, person, and case, they refer to the same person or thing, and when the second is put in order to explain or add something in meaning to the first. The essence of apposition is in the fact that a word or words are apposed (ad, to, and pono, I put), with a view to explain, enlarge, or qualify a foregoing noun or pronoun. Observe that in every case of apposition there are two parts, the apposed part, and the part to which the apposition is made. Thus, in the sentence, “Richard, the king, lost his crown,” the king is the apposed part, and Richard is the part to which the apposition is made. You will now readily see that the added part will partake of the person as well as the number of the part to which the addition is made. Call the latter the principal part; call the former the subordinate. Then the rule may stand thus:— In apposition, the subordinate part agrees with the principal opart. And this agreement will in general be not only in person and number, but also in gender and in case; so that if the principal part is of the feminine gender, in the feminine gender will the subordinate part be ; and whether the principal part stand to the verb of the proposition in the relation of subject or object, in the same ° relation will the subordinate part stand. In the sentences, “It is I; it is the Lord ; the Lord sitteth king for ever,” and others in which the second noun or pronoun aids to make up the intended idea, the second must of course have the same grammatical relations as the first which it aids. Thus, king has the same grammatical relations as the Lord. In other words, the rule may be stated thus:— The verb to BB, and other verbs which in themselves do not €397.86s a complete idea, take the same case after as before them. Consequently, to say “It is me,” in answer to the question “who is that P* is ungrammatical. Remark, however, that it, used generally, is an exception so far as gender and number are concerned, for it is idiomatic to say

It is she, it is he, it is they, it is we. Apposition may be regarded as a case of a compound sentence, and so might have been reserved until we treat of that part of our subject. Thus, in the instance “But he, our gracious master, kind as just.”—Barbauld. may be written out in full in this way:— He who is our gracions master and who is kind and just. CORRECT THE FOLLOWING INAccuRAcIes. The master and mistress is going to town. I loves to see boys at play. The consequence of your follies are that you will be miserable. To die and to be no more is not the same thing. You gives the children too many sweetmeats. Let thou and I serve the Almighty. “Do not think such a man as me contemptible for my garb.”— 28072. “His wealth and him bid adieu to each other.”—Priestley. “The Jesuits had more interest at court than him.—Smollett. “We sorrow not as them that have no hope.”—Matarin. “A stone is heavy and the sand weighty; but a fool's wrath is heavier than them both.”—(Prov. xxvii. 3.) “Better leave undome, than by our deeds acquire Too high a fame, when him we serve 's away.”—Shakspeare. “Now therefore come, let us make a covenant, I and thou.”—(Gen. xxxi. 44) “Yet I supposed it necessary to send to you Epaphroditus, my brother, and companion in labour, and fellow-soldier, but your messenger, and he that ministered to my wants.-(Philipp. ii. 25.) “Amid the tumult of the routed train, The sons of false Antimachus were slain ; He, who for bribes his faithless counsels sold, And voted Helen's stay for Paris’ gold.”—Pope’s Iliad. co The first, the court baron, is the freeholders' or freemen’s court.”— ke. “The angels adoring of Adam is also mentioned in the Talmud.”—

“It was necessary to have both the physician and the surgeon's advice.”—Cooper. “And love's and friendship's finely-pointed dart lo'alls blunted from each indurated heart.”—Goldsmith.

:SKELETON MAPS.—No. TV.
AFRICA.

OUR Map of France, with the Railways, not being ready for this number, we have inserted, for the use of our Geographical Students, a Skeleton Map of Africa, which they would do well to endeavour to fill up, as we trust they have done the former Skeleton Maps, from the lists of the Latitudes and Longitudes of places given on the margin or in the text.* Under the vacant space in the left hand corner at the bottom of this Map, intended for the name AFRICA, is a scale of British miles, of which each division stands for 100 miles distance on the Map. The middle parallel of Latitude, marked 0 at both ends, is the Equator; from this parallel, the Latitudes which are marked 10, 20, 30, &c. on the sides, and proceed upwards to the top of the map, are North Latitudes; and those which are marked 10, 20, 30, &c. on the sides, and proceed downwards to the bottom of the map, are South Latitudes. The dotted parallels of Latitude are the tropics; the one in Lat. 23° 28' N. being the tropic of Cancer, and the other in Lat. 23° 28′ S. being the tropic of Capricorn; between these two parallels, the sun shines vertically at noon on every place of the torrid zone, two days in the year.

In laying down the Latitudes on this map, there will be little or no difficulty, inasmuch as the parallels of latitude have been made parallel straight lines; only let it be observed that every black or white space on the sides of this Map must be reckoned two degrees of Latitude, that is, 120 Geographical miles, or about 140 British miles. In laying down the Longitudes, however, there will be considerable difficulty, owing to the curvature of the meridian lines. This will be obviated by graduating with a pencil the Equator, or the parallel of Latitude marked 0 at both ends, exactly like the degrees of Latitude at the sides of the map; for on the Equator the distance between one degree of Longitude and another is exaetly equal to the distance between one degree cf Latitude and another

* The list of the Latitudes and Longitudes of the Capitals or Chief Cities in Africa will be found at page 62, vol. iii., of the “Popular Educator.”

on any meridian. Supposing, then, that the Latitude and Jongitude of a place are given, and you wish to find its place on the map in order to lay it down; supposing, also, that the Equator has been so graduated as we have said, and that the degrees of Longitude are marked at every 10 degrees, exactly like the degrees at the top and bottom of the map; then place a piece of whalebone, or other equally flexible substance, on the given degree of Longitude at the top, at the Equator or middle, and at the bottom, and it will assume very nearly the proper curve form of the meridian ; while in this position, make a mark close alongside the piece of whalebone at the given degree of Latitude, and this mark will represent the exact position of the place on the map whose Latitude and Longitude are given. Remember, however, that every black or white space at the top and bottom of this map must be reckoned two degrees of Longitude, or 120 miles of Longitude ; these degrees or miles of Longitude vary in size according to their position on the map, —a fact which must be sufficiently obvious to the attentive reader, seeing that the meridian lines taper towards the poles both northward and southward, and that all meridian lines do actually meet at the poles on the globe itself. The following table will show the exact size of the -degrees of Longitude in Geographical miles of Latitude according to their distance from the Equator; if the size of these degrees be wanted in British miles, you have only to add to the number of Geographical miles given, one-sixth part of itself, for a first approximation to the truth ; to obtain the next approximation, a very close one, deduct one-tenth of the preceding sixth-part from the first approximation, and you will have the number of British miles required. Suppose, for example, that you wished to know the length of a degree of Longitude in Lat. 40° north or south of the Equator. Look in the table, in the column marked Deg. Lat. for 40, and in the adjoining column to the right marked Geog. miles, you will find 45'96; this shows that the length of a degree of Longitude in Lat. 40°, is only about 46 Geographical miles, or exactly 45 ‘such miles and 96 hundredth parts of a mile. In order to find the number of British miles, take one-sixth part of 45'96, which is 7-66, and add this part to itself; this gives 53-62 for a first approximation to the truth; next take one-tenth part of 7-66, which is 766 or 77 nearly, and deduct this part from 53-62, the first approximation; this gives 52-85 for the next approximation. Thus, we find that a degree of Longitude in Lat. 40° is only 52.85 British miles.

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o The trigonometrical rule for the construction of this table, is to multiply 60 Geographical miles, the length of a degree of Longitude on the Equator, by the cosine of the given Latitude, the product will be the length of a degree of Longitude in the given Latitude.

LESSONS IN ITALIAN GRAMMAR.—No. I.

By CHARLES TAUSENAU, M.D.,

Of the University of Pavia, and Professor of the German and Italian Languages at the Kensington Proprietary Grammar School.

INTRODUCTION.

I propose to teach the grammar, structure, and vocabulary of the Italian language by a method not commonly adopted by the learned. A considerable experience in tuition has convinced me that a strict adherence to scientific forms, though all-important in the cultivation of a language, does not tend to the advantage of the learner. Writers of practical grammar err, for the most part, in studying system too much. They teach grammar as they would the pure mathematics, as if an abstract science of itself, and not as a practical guide through the idiomatic intricacies of living languages. Such instructions may be very scientific in form, but they do not follow nature. There is no due separation of that which is the foundation, or as it were the skeleton of a language, from those things which are the ornaments, the delicacies, the accidents and exceptions of speech. A language should be taught as anatomy is taught. We must first thoroughly study the bones, if we would successfully trace the intricate ramifications of nerves and arteries. The learner of a foreign tongue cannot for himself judge of what is material or immaterial to his sure and rapid progress. It will be my endeavour to instruct by a colloquial and natural, rather than a grammatical and purely scientific method. The Italian language has for a long time been regarded in this country as a fashionable branch of education. Knowledge of it has been reckoned an indispensable accomplishment of cultivated society, but rather, as it would seem to me, as a serviceable attendant at Italian picture galleries and operas, than as a guide to the philosophy of a Dante, the invention of an Ariosto, or the sagacity of a Machiavelli. The present is perhaps the first considerable attempt that has been made to popularise this noble and melodious tongue. The Italian is the first born of the old language of Rome, and owns a strength and beauty worthy of its noble origin. In cultivat-on, it is the oldest of European tongues. When Dante wrote, English, French, and German were comparatively rude dialects. To Italy, the world owes the preservation and regeneration of learning and the Arts; and its fine soil, the fertile mother of great spirits of old, has produced to the latest times men who have enriched every intellectual pursuit alike by their genius and learning. The language in which they expressed that infinite variety of thought and sentiment, contains a literature, the rich mine of which is in foreign countries only known to solitary and toilsome explorers. The time may not be distant when the increased intercommunication of nations, and the progress of popular education, will lay these rich treasures open to the many. For its own intrinsic merits, however, as a language, Italian deserves to be studied by every one who would enjoy the pleasures of style, inexhaustible in variety: the energy of Dante, the graphic power of Boccaccio, the lyrical grace of Petrarca, the refinement of Ariosto, the ornament of Tasso, the satire of Berni and Aretino, the historical dignity of Guicciardini and Botta, the point and perspicuity of Macchiavelli, the hilarity of Casti, the music of Metastasio, and the Roman manliness of Alfieri. And they who would cultivate language for its excel lence must seek that of Italy for the ideal beauty of expression. My method will be a matural, a simple, and, I trust, an easy one." I shall discard, as much as possible, all the conventional terms of grammar. I shall not travel by the old beaten pathway through the parts of speech. My grammatical progress will imitate the action of the mind in the formation of a sentence, with a due regard to peculiarities of idiom. As a child first learns the name of a thing, I begin with the noun, as soon as I have clearly explained the principles of pronunciation ; and as the child demonstrates its progress in thinking, by connect:

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ing an action or suffering with the object named, I shall

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