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cat circular-a flat piece of tin or sheet-brass will do as well; where it is diluted with nitrogen. This the following experi-
place one hand upon this to prevent it falling off, and with the ments will show :-
other hand lift the jar and invert it into the dish. In Fig. 17 1. Twist a wire round a piece of charcoal (Fig. 19). Take
it will be seen that the jar stands on two pieces of slate, one of the jars of gas standing on the plate, and replace it
parted with about half an inch between them, thus allowing in the dish of water; remove the plate, and in its place put the
room for the delivery tube to pass beneath. When a jar is full circular piece of

of the gas, pass a small plate glass ; lift it
beneath its mouth, and lift from the water
it out of the water; it will and stand it on
stand in the plate as long as the table, mouth
required, if the hollow of the upwards; hold
plate be left full of water. the charcoal in
Another jar should be stand the flame of the
ing in the dish ready to be lamp until some
filled; and as with one parts of it are

hand the full one is re- red; with
Fig. 17.

moved, with the other the hand slide the

second one should be placed glass off the to receive the gas. The chemical action is expressed and ex- mouth of the jar plained in this equation

sufficiently to KC10,= KCl + 0,;

admit of the en

Fig. 19. that is, potassium chlorate, when heated, becomes potassium charcoal, and the charcoal will burn brilliantly in forming with

trance of the chloride and oxygen.

Do not place the flask on a cold substance while it is hot, but the oxygen carbonic acid gas (CO2). when cold fill it with water; after a few shakes pour it into a

2. Place in the “deflagrating spoon "-which is a small metal tall jar, and add more water. The potassium chloride is very cup soldered to a piece of wire (Fig. 20)-some sulphur; light it soluble, and the unaltered MnO, goes to the bottom; let it —it burns with a pale blue flame; introduce it into a jar of stand all night, then pour off the “ supernatant liquid;" fill the oxygen—it burns brightly into so, (sulphurous acid), which jar again with water, and again let the Mno, subside; pour off causes the well-known suffocating smell. the clear water, which contains the last traces of the KCl, and

3. Repeat this experiment with phosphorus. The student is. throw the Mno, upon a filter, and afterwards dry it; it is then advised to use the red amorphous phosphorus, which is not so fit again for use. This will give the student some practice in inflammable as the stick phosphorus. An intensely brilliant manipulation, but practi

light is emitted during the formation of the cally it is not worth the

white fumes, which are phosphoric acid (P,05). trouble, since the Mno, is

4. The following experiment is very illustraso cheap.

tive of the fact that burning is chemical combi. 3. Oxygen may be got,

nation. Take a piece of fine iron wire-such when large quantities are

as that of which “ribbon-wire" is made; coil required, with more economy

it into a spiral, round a pencil; stick the end from the black oxide of

of it into as small a piece of cork as you can ; manganese itself; but since

dip this into any inflammable liquid, such as great heat is required, an

naphtha ; pass the other end through a hole iron bottle must be used, as

in a disc of tin; light the cork, place it in a in Fig. 18. In this bottle

jar of oxygen, as in Fig. 21, and the wire will the delivery tube is passed

burn with beautiful scintillations into Fe,O,

Fig. 20. through a cork in the end

which is the same oxide of iron as the lodestone. of the pipe. The retort

It is better to fit a piece of cardboard in the bottom of the is filled with manganese jar, and leave about an inch of water in it:

for the fused oxide broken into lumps about the is so hot that if it touch the glass the jar will crack. Fig. 18. size of a pea; then the pipe

From the above modes of preparing oxygen we may take

is screwed in, and, to ensure examples of one method of finding what weight of the subperfect tightness, the screw is luted with white lead.

stance is required to give a certain quantity of another. The action is

Take the equation

KCIO, = KCl + 0, ; 3Mn0, = Mn,O, + 0,;

the atomic weights of these elements are that is, the peroxide has been by the heat reduced to a lower

39.1 + 355 + 48 = 39-1 + 35:5 + 48 oxide,

122-6 = 746 + 48. 4. A process which answers well, and which is more economical That is, from every 122:6 parts by weight of potassium chlorate, than that in the second, is the following :- Take 3 parts by weight 48 parts by weight of oxygen come off ; of pulverised potassium bichromate (K,0,2Cr0,-1, atom of or, from 100, 39-2 come off; that is, 1 potash and 2 of chromic acid), and 4 of sulphuric acid (H2SO); kilogramme of the salt gives off •392 of heat it in the Florence flask, and the chromic acid parts with the gas, or nearly / kilogramme.

AgainK,0,2010, + 4(4,50.) = K,,80, + Cr2,380, + 41,0 + 30.

3M50,=Mn,0, +20. The compound under the line is chrome alum.

3x55 +3 2 16 = 3 x 55+4* 16+2 x 16 Combustion is simply chemical combination, and when this

261 = 229 + 32 ; combination is violent, sufficient heat is developed to produce that is, from 261 parts of manganese fire.

by weight we get 32 of oxygen, or about The affinities of oxygen are remarkably strong, and it is of the weight of the MnO,. But the capable of entering into combination with every body in nature commercial black oxide of manganese except Fluorine; therefore fire is generally oxygen entering into is seldom very pure, and usually yields

Fig. 21. combination with the body burning ; though we shall find about half this weight of gas-a pound instances of this phenomenon in which oxygen takes no part. giving off about 1,400 cubic inches. The relation between

In the fires of our houses the oxygen of the air is combining volumes and weights will be given in due time. with the coal, which is carbon, to form an invisible gas, car- Ozone is the allotropic form of oxygen ; that is, it seems to be bonic acid gas (co,), which passes up the chimney. Hence we oxygen in “another form," probably condensed, and therefore say that oxygen is the great supporter of combustion. Of course more active. It is produced by the slow oxidation of phosphorus. combustion will be more violent in the pore gas than in the air, If a piece of this substance be placed at the bottom of a jar in

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half its oxygen.

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- - jas of contempt" ascribed to it by Latham does not

sessiy, for it did not originally, belong to the word.

.: 23 de a swift witness against those that defraud the kireling in 's S-Xalachi iii. 5 (compare Job vii, 1, 2; xiv. 6).

is may be connected with the Latin stirpes, stirps, S; so that stripling is a little branch, a youngster.

- He is but an yonglyng,

A tall, worthy stryplyng.”—Skelton. Sisse shows that nothing contemptuous belonged to the el z sie den time. Consult the ensuing :

« Now a stripling cherub he appears, Sot of the prime, yet such as in his face

Toth smiled celestial."— Milton, "Paradise Lost," :.anastion of Saron origin, having the force of our like,

sic e sdjective or an adverb; as childlike, childły, zisusadas; manlike, manly, manlich. When ly is added

se sfees sa sdjective, as love, lovely; when it is added

:: se süjetre, it forms an adverb, as wise, wisely. Such a ... :emstion as a helily” (1 Thess. ö. 10) is to be avoided for the * sake of euphony.

Ment, from the Latin mentum (as in ornamentum, an ornament; adjumentum, an assistance), throngh the French ment (as in the

French mandement, or Latin mandatum, a command), is a suffis V::::SH-XVIII.

which denotes the result of the art sbcated in the verb from which the noun is derived : thus, vals mens I veil or cover ; and

velamen or velamentum is a ver or catering ; so aliment (from wasio nawawal by abbreviation; the word the Latin alo, I nourish) is a means wishing, nourishment.

Herved rulu the Latin omnibus,” Hence, devotement properly indicates set the act, but the result; imber of whe Latin adjective omnis, not the doing, but the state of feeling which ensues from the doing,

That is every man's carriage--the the devotion. In practice, however, the ssage seems reversed. mandulo "tes, and so it is now generally “Her (Iphigenia) devotement was the demand of Apollo."—Hurd. Yob appears to have been formed

"Oh, bow load
When Uw wled the mob used to be called

It calls devotion genuine growth of night!
With lobble aro wobile vulgus, a fickle crew,

Devotion! daughter of Astronomy!
I bedes vulguis, and by contraction, mob.

An undevout astronomer is mad"
nu uut dontical. Rabble is the general

Tomg, "The Complaint." publik oollootion of persons belonging to

Tilitated form of the now more fashion- It is our intention now and then to enliven our lessons with a ihlwill alw and eleemosynary there would conversation on English grammar, supposed to be held between

um tuum; both, however, come from the same an educated man on the one hand, and one whose education is

and the fumer is only a shortened form of the imperfect on the other. We do this because there are many Lire la chaus luctor is derived. Well do we remember of our readers who may gain much useful information from a in un uur youthful days, used to signify some- lesson brought under their notice in a conversational form, that

Little did we then suspect that it was they may fail to gather from lessons written in the ordinary 1. I way of pronouncing the French quelque chose ; way. We therefore recommend our readers to study the folAs womb.mptuously travestied to mimic and ridicule lowing dialogue with care, and endeavour to re-write the substance "Ritu Lugland,

of it from memory when they have read it over three or four Heim. Alusta Haxon cyn, kin, offspring, son, signifies times, and noted the principal points in it. 4. u Walkın (Wilkins); seen in another form

CONVERSATIONS ON ENGLISH GRAMMAR.-I. kin from its signification, has also a diminu. in balkon (a lamb's child), or little lamb. What William. Well, I have failed again; a packer I

and a We diminutives are terms of endearment. packer I must remain, fond as I am of reading, and desirous as De wind tuy bo despised. Sometimes, therefore, I am of getting an employment more suitable to my tastes. mwi larutasimpt; as in manikin.

And yet, if I had fair play, I could, I am sure, do the connting.

house work as well as some that are there. I thinnekan to you, Sir Toby."- Shakespeare.

Thomas. Not quite, William ; true, you are intelligent and 1, "tidshof the suffixos already given.

trustworthy; you also write a good hand, and are ready at 1. A Video saxon læs (German, los, destitute of), has accounts; but you are a very poor grammarian. , nire but a negative force; as, an læs twentig, William. Not so poor as you think; though I am, I grant,

s tem we should say, twenty minus one. Hence far behind you, Thomas; but then you have been to college, otra Notebook of less is privation or negation. Con and ought to know grammar.

# , tiparative of little, is altogether a different Thomas. Yes, and I am willing to teach you, for I am sure
* v* w www also led to understand the true force you will never get forward as you wish, and as I should like to

modellery a suffix; as, motionless, or without see, until you can write your mother tongue correctly.
law, from from death. Two negatives thus make William. I know that, and I have studied English grammar;
de privation of life, and less, the negation of but it is very difficult.
Me Ama the idea of ever-enduring existence, Thomas. Yes, and you still write bad English: for instance,

the mout zoal, the most permanent of all con- your letter of application for the vacant situation contains not w Yory basence of Deity ; life itself.

less than three grammatical mistakes, and is enough of itself to welathon, noems to be double, and to consist prevent your success. How can you expect to rise in the world wiele and the French diminutive t;" It when you cannot speak and write English? In a counting that, buanlet (Anglo-Saxon, ham, home; house they want their letters written grammatically. It would

be a disgrace to a house to send out letters containing errors of dumaton llescent, and hence offspring; grammar like those which you commit. w that which is beloved ; e.g., darling William. I dare say you are right; and so I must remain a wywar), welding, Hireling is properly packer.

whore kurvives aro obtained by hire. Thomas. That does not follow; learn the English grammar.

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William. A very easy precept, but a very hard job.

LESSONS IN DRAWING.-XVIII. Thomas. Not so hard as you think. William. Excuse me, I have tried, and I have failed.

TREATMENT OF REFLECTIONS IN WATER. Thomas. Because you have tried by yourself.

It is not the rule that because we can see the objects we must William. By myself I must still try, or give it up.

consequently see the reflections; and, on the other hand, it is Thomas. No, I will assist you, if you will make one more very common to see the reflection of an object, or of light, when effort. Let us talk over the matter; I thi. k I can make the the eye does not see the object itself, something intervening study easy to you. Once a week we will cc iverse together on between the eye and the object, but not between the eye and the English grammar, and if you will only reflect in the intervals reflection. The leading principle, upon which is founded all on what I say, and follow my guidance, I have no doubt you other data connected with our subject, is that the reflections of will in time understand the subject thoroughly.

all objects and their parts are always perpendicularly beneath the William. I agree, and am very much obliged to you for the objects and the parts themselves respectively. Fig. 112, a simple offer.

subject of posts, etc., will explain this. The top of the post a Thomas. Oh, never mind the obligation; men should always is perpendicularly over the reflection b, and so with the rest; try to assist each other, and I am very desirous to see you in but it must be borne in mind that the proportion to be drawn such a position as your character and talents mark you out for. of the reflection of an object is regulated by or according to William. Let us begin this evening.

the position of the object, and also with regard to the point Thomas. Very well, and you must come to my house every from which we view it. If we view the posts (Fig. 112) as they Tuesday evening at eight o'clock, and we will see what can be are drawn, perpendicularly and parallel with the picture plane done. But to begin :-As a fundamental rule, you must observe that is, the upper parts neither advancing towards the eye that grammar is a science in which authority goes a very long nor receding from it, but exactly over the position of the lower way. At first, you will do well to consider that everything parts—then the reflections will be the same in length, with the depends on authority.

slight exception resulting from the perspective of distance. William. What authority ?

We will endeavour to make this clear by the help of a few Thomas. That of the best writers in the language. If you problems. In order fully to understand these problems, we study English grammar, then you take as your authorities or recommend the pupil to work them out, and as the principles guides such men as Shakespeare, Milton, Dryden, Johnson, of construction are the same throughout, we advise him to Pope, Macaulay. Their practice is your model. As they write, repeat them with a few of the conditions varied-for instance, 80 you must write. Grammar then, you see, is, for our purpose, greater or less inclinations of the slopes, and greater or less imitation. Those who write English grammar derive the in- elevations of those objects which are most in advance. Our structions they offer from the usages of the best English authors, first subject will be to draw the reflection of a wall (Fig. 113). or, as they are termed, the English classics.

Let A be the end section of a wall situated on the margin of a William. “Classics !" why, I thought the term "classics” was river. It is required to show its reflection, B, below the water's confined to the Greek and Roman authors, such as Homer and edge, CD; s being the position of the eye on the horizontal line. Virgil.

Draw a line, sts?, perpendicularly as much below the base CD Thomas. Oh, no; every literature has its “classics.” The as it is above it, making s? E equal to s' E. From the upper part word is derived from “ class," and denotes those writers who, of the wall F draw a line to s?, and where this line cuts the by common consent, are placed in the first class. The practice base c p in will give the point through which a line is to be of such writers sets the fashion in the language in which they drawn from si to meet a perpendicular line from F, which will write, and they are followed by all who wish to speak and write give the depth of the reflection required. Now in order to that language correctly. Now you are to suppose that I have apply the above rule in showing the face of the wall and its studied our English classics, and have hence ascertained how I reflection, we must proceed as follows :-In Fig. 113 draw at ought to speak and write. In that study I have been preceded pleasure the line acdb, and repeat this line, with its respective by others. Their conclusions afford me aid. Under that aid divisions, in Fig. 114 ; through the several points a cdb draw I have formed a system of rules, and that system of rules is horizontal lines at right angles with ab; make A B equal to called “ English grammar." English grammar, then, you see, the length of the given wall, and draw the rectangle A GHB; is a science. Science, you know, means knowledge; it is know- | ABFE will represent the wall, EFHg the reflection. The ledge, the materials of which are systematically arranged; pupil must be reminded that the line a cdb in Fig. 113 is the arranged, that is, into a system, arranged in a set order, picture plane or medium through which we see the wall, and and with a view to a certain purpose or result; and English upon which it is supposed to be traced (see Vol. I., page grammar consists of a continued set of rules derived from the 72, Def. 3, “Station Point”). We have previously observed practice of well-educated Englishmen, so arranged as to form that in consequence of the position of the eye being above the a complete whole, and communicate useful information to the reflection, and on a level with some portion of the object, it learner.

will repeatedly occur that the reflections of many parts of the William. Well, I understand that; but in our house every- solid cannot be seen, although the parts themselves are in sight, body says “they does," and you told me yesterday that was and form, perhaps, the most important portions of the object. wrong.

Let us illustrate this by Fig. 115, which is a mass of masonry, Thomas. It is wrong; remember, I said that we are guided having two slopes, A and B. Having drawn the profile or by the practice of educated Englishmen, and educated English- section G, proceed as in the last case, being careful to draw lines, men say, " they do."

or visual rays, from every angle to s', and also to sa. Where Wiliam. But what does the word grammar signify? I these rays cut each other respectively in w, t,9, lines from gl will thought a grammar was a book; you say it is a science. determine the lengths of the reflection. We must apply this to

Thomas. It is both. Grammar is a word of Greek origin. a front view, as in the former case. Draw the perpendicular It comes from a Greek word, ypapua (gram'-ma), which denotes line E E' (the picture plane), and mark the points where the a letter, a letter of the alphabet. Hence grammar is the science visual rays cut the picture plane in a, b, c, etc. Repeat this line of letters-letters, that is, employed to express ideas. Listen: in Fig. 116, and copy from Fig. 115 the distances of the diviletters represent sounds, and form syllables and words; words sions upon it, and proceed with the horizontal lines from these represent sounds; and the sounds they represent stand for distances as in the last problem. Upon the line marked g, thoughts or ideas; while those thoughts or states of mind which represents the water's edge, make PG equal to the given represent things, objects in the inner world or in the outer length of the wall; d being the horizontal line, and the observer world. This statement will require thought. Do not trouble being supposed to stand opposite the centre of the wall, the point yourself too much about it now; you will understand it by-and- of sight will be at p s. Now the lines F P8 and GPS are hori. by. But observe that grammar is the science by which you zonta! lines in perspective—that is, the perspective of the base learn to express your ideas correctly, that is, according to the 9(Fig. 115): therefore, where the visual rays from the points usages of the best authors. And a book in which these usages in the base cut the picture plane in f (three lines close together) are set forth as rules is also called a grammar. Every language will give the points, k, l, m, whence the perpendiculars of the has rules peculiar to itself. Hence we have “French grammar,'

," wall must be drawn, the lower slope in must be drawn “Greek grammar," as well as “English grammar.”

betweon the lines e, 9 (see Fig. 115), and the perpendicular

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ko; the same with the upper slope. The reason why neither for himself. The same may be satisfactorily proved with of these slopes are seen in the reflection is because the point regard to clouds. It is common, also, in their cases to see P coincides with g (Fig. 115) on the picture plane: therefore the brilliant reflections of light clouds on the water, when to the same line, FG, represents both extremities of the slope. If the eye there is nothing to account for them. These reflections slope B had had a greater elevation—that is, had it been at a are invariably caused by light clouds which are hidden from greater angle

view behind - then the

other clouds, upper extre

the reflections mity would

affording us have admitted

the only evi. a line to sa,

dence of their and conse

existence. quently would

Why is this? have cut the

And where is picture plane

the root of the EE at a higher

mistake that point than g;

is so frequentand that point

ly made, that, of intersection

withoutexcepwould have

tion, whatever been shown below g in the

We paint above

the water must reflection. And

be necessarily also for rea

repeated by Bons given

its reflection? above, we see

It is simply parts reflected which are not

this, that visible in the

many treat

the whole objects them

view, sky and selves. Figs.

all included, 117 and 118

as one single will satisfy the

plane, never mind upon Fig. 112.

thinking there this point.

are parts more The subject is a cottage on a bank with a large notice-board in remote than others, and consequently many are reflected which front of it. The profile view (Fig. 117) will explain the disc are shut out from the eye by intervening objects. tance of the board from the cottage, and this will account for Water not only receives reflections, but, conditionally

, is the great difference between the details of the projection A and capable of receiving shadows. If the water is perfectly clear, the reflection B in Fig. 118. If the pupil fail not to work no shadows occur, and the reflections are more or less vivid in out this problem

proportion as the also (of which,

water is more or being constructed

less impregnated by the same rules

with colouring as the former, we

matter, say clay, give no detailed PP

or as rivers geneexplanation, but

rally appear after prefer leaving it

heavy rains. Then as it is, for an

the strength of exercise), he will

the reflections and more readily un.

shadows alternate derstand it, and Fig. 118.

in proportion to the method of

the clearness or construction also;

opacity of the remembering that

water. When it the visual rays

is very thick and drawn from every

muddy, the shar important point of

dows of objects the whole passing

are cast as forcibly through P P (the picture plane) de

as they are on a termine the points

road; and as it to be transferred

becomes clearer, to the correspond

the reflections be ing plane on the

come more brilleft in Fig. 118.

liant and the Wo remark that

shadows weaker: the notice board

the earthy parcovers part of the

ticles mingled with roof in the pro

the water receive zootion A, whilst

the shadow, not it is clear of the

the water itself. roof in the reflection B. Also compare the chimneys in both In perfectly clear water the light passes through the water omen with rospect to their apparent position with the board. itself, as through a piece of glass, lighting up the bed of the In the reflection the sills of the windows are on a line with river, so that we are able to distinguish readily the stones,

of the post, and the thresholds of the doors cannot weeds, fish, and whatever else may be at the bottom; then the sponse they are hidden by the bank. There are shadow which falls upon the water sinks as it were, and is seen

noon, which the pupil will be able to discover at the bottom only.

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