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their extremities in any manner whatever, except that of uni- application. These were so generally adopted, that we may form direction. A curved line, or curve, is a line whose direction consider the Manutii as the inventors of the present method of varies at every point.

punctuation; and although modern grammarians have introduced Straight lines, or curved lines, are generally denoted, in some improvements, nothing but a few particular rules have speaking and writing, by two letters placed commonly at their been added since their time. extremities; but they may be

The design of the system referred to was purely grammatical, placed anywhere on the lines

and had no further reference to enunciation, than to remove at a distance from each other.

ambiguity in the meaning and to give precision to the sentence. Thus, in Fig. 1, the letters ABD

This, therefore, is the object of punctuation, and although the denote one straight line, the

marks employed in written language may sometimes denote the letters C D another, and the

different pauses and tones of voice which the sense and accurate letters E F a third ; and these

pronunciation require, yet they are more generally designed to straight lines are respectively

mark the grammatical divisions of a sentence, and to show the called the straight lines A B,

dependence and relation of words and members which are OD, and E F. A straight line,

Fig. 1.

separated by the intervening clauses. The teacher, therefore, as A B, may be divided into

who directs his pupils to “mind their pauses in reading,gives any number of equal parts, to serve as a standard for measur. but an unintelligible direction to those who are unversed in the ing other straight lines.

rules of analysis. A better direction would be to disregard A combination of straight, crooked, and curved lines is re- the pauses, and endeavour to read the sentence with just such

presented in Fig. 2; A B, BC, C D, and D A, pauses and tones as they would employ if the sentence wero are each straight lines; the combination their own, and they were uttering it in common conversation. ADC B, beginning at a, and terminating Indeed, it is often the case that correct and tasteful reading at B, is a crooked line; and the line AM B, requires pauses, and these too of a considerable length, to be beginning at A, and ending at B, is a made, where such pauses are indicated in written language curved line.

by no mark whatever. It is not unfrequently the case that the Fig. 2.

6. A surface, or, as it is sometimes sense will allow no pauso whatever to be made in cases where, if called, a superficies, is extension in two directions ; hence it is the marks alone were observed, it would seem that a pause of said to have only length and breadth. Hence, also, the extre- considerable length is required. The pupil, therefore, who has mities or boundaries of a surface are lines; and surfaces inter- been told to mind his pauses, must first be taught to unleam sect or cross, each other in lines.

this direction, and endeavour to understand the sentence which 7. A plane surface, or plane, is a surface in which any two he is to read, before he attempts to enunciate it. points being taken, the straight line between them lies wholly The characters employed in written language are the followin that surface; or, it is that surface with which a straight line ing :wholly coincides, when applied to it in every direction. Any The Comma,

The Hyphen, other surface, not composed of plane surfaces, is called a curved. The Semicolon,

The Breve surface.

The Colon,

The Apostrophe, ['tis] 8. Parallel straight lines are such as lie in the

The Period,
The Dash,

The Brace, same plane, and which, though produced ever so far

The Exclamation,

The Acute Accent, both ways, do not meet (Fig. 3).

Fig. 3.
The Interrogation,

The Grave Accent,
The Quotation Marks

The Circumflex Accent,
The Diæresis,

The Caret,

The Crotchets,

( The Cedilla, The Brackets,

[] The Asterisk, PUNCTUATION.

The Obelisk or Dagger,

The Section,

$ PUNCTUATION is peculiar to the modern languages of Europe. The Double Obelisk or

The Paragraph, It was wholly unknown to the Greeks and Romans; and the Double Dagger,

I The Parallels, languages of the East, although they have certain marks or The Ellipsis, sometimes expressed by Periods, thus, signs to indicate tones, have no regular system of punctuation.

sometimes by Hyphens, thus, The Romans and the Greeks also, it is true, had certain points,

sometimes by Asterisks or Stars, thus,

sometimes by a Dash prolonged, thus, which, like those of the languages of the East, were confined to the delivery and pronunciation of words ; but the pauses were These characters, when judiciously employed, fix the meaning indicated by breaking up the written matter into lines or para- and give precision to the signification of sentences, which, in a graphs, not by marks resembling those in the modern system of written form, would be ambiguous or indefinite without them. punctuation. Hence, in the responses of the ancient oracles, Thus, “I said that he is dishonest it is true and I am sorry for which were generally written down by the priests and delivered it.” Now the meaning of this sentence can be ascertained only to the inquirers, the ambiguity-doubtless intentional—which by a correct punctuation. If it be punctuated as follows : "I the want of punctuation caused, saved the credit of the oracle, said that he is dishonest, it is true, and I am sorry for it;" the whether the expected event was favourable or ning will be, that it is true that I said he is dishonest, and I As an instance of this kind, may be cited that remarkable am sorry that I said so. But if it be punctuated thus, “I said response which was given on a well-known occasion, when the that he is dishonest; it is true; and I am sorry for it ;" the oracle was consulted with regard to the success of a certain meaning will be, “I said that he is dishonest; it is true that he military expedition : “Ibis et redibis nunquam peribis in bello.” is dishonest, and I am sorry that he is so." Written, as it was, without being pointed, it might be translated A further instance of the importance of correct punctuation either, “ Thou shalt go, and shalt never return, thou shalt perish was afforded by a late advertisement, in which the commissioner in battle," or, " Thou shalt go and shalt return, thou shalt never for lighting one of the largest commercial cities of Europe, by perish in battle.” The correct translation depends on the the misplacing of a comma in his advertisement, would have conplacing of a comma after the word nunquam, or after redibis. tracted for the supply of but half the required light. The

The invention of the modern system of punctuation has been advertisement represented the lamps as “4,050 in number, having attributed to the Alexandrian grammarian Aristophanes, after two spouts each, composed of not less than twenty threads of whom it was improved by succeeding grammarians ; but it was cotton.” This expression implied that the lamps had each two 80 entirely lost in the time of Charlemagne, that he found it spouts, and that the two spouts had twenty threads—that is, necessary to have it restored by Warnefried and Alcuin. It each spout had ten threads. But the meaning that the comconsisted at first of only one point, used in three ways, and missioner intended to convey was, that each spout had twenty sometimes of a stroke, formed in several ways. But as no par- threads; and his advertisement should have had the comma ticular rules were followed in the use of these signs, punctuation after “spouts," instead of after “each,” thus: The lamps have was exceedingly uncertain, until the end of the fifteenth century, two spouts, each composed of twenty threads, etc. when the learned Venetian printers, the Manutii, increased the number of the signs, and establishod some fixed rules for their * The term "written language" of course includes printed language.

! ?


These instances might suffice to illustrate the nature and the words signum sectionis, or the sign of a section. This character, propriety of correct punctuation ; but the following instance, wbich was formerly used as the sign of the division of a disknown to many, will show the importance of the subject. The course, is now rarely used, except as a reference to a note at derk of a congregation in Scotland had a paper handed to him, the bottom of the page. as the custom is, to read just before the minister stood up to The word Paragraph is derived from the Greek langnage, and pray with and for the congregation, containing the following signifies a writing in the margin. This mark, which, like the words, unpointed: “A man going to sea his wife desires the section, was formerly used to designate those divisions of a prayers of the congregation.” The clerk read it as if a comma section which are now indicated by unfinished lines or blank had been put at the end of the word wife, and unfortunately spaces, is employed in the English version of the Old and New excited, in no small degree, the risible faculties of the people Testaments to mark the commencement of a fresh subject. assembled :—thus, “A man going to sea (see) his wife, desires It may further be remarked, that notes at the bottom of the the prayers of the congregation.”

page, in the margin, or at the end of a book, are often indi. But although the meaning of a sentence is thus materially cated by figures or by letters, instead of the marks which have affected by the punctuation, it will be seen in the following already been enumerated. lessons that the punctuation alone is an unsafe guide to follow The word Caret is from the Latin, and signifies it is wanting. in the enunciation of any collection of words. For, in many This mark is used only in manuscripts. cases, these marks indicate no pause, emphasis, or other circum- The Cedilla is a mark placed under the letters c and g to indi. stance requiring notice in the enunciation of the sentence. cate the soft sound of those letters.

The nature of the marks used in written language may also be The Asterisk, Obelisk, Double Obelisk, and Parallels, with the mnderstood by a reference to the origin of their names.

section and paragraph, are merely arbitrary marks to call atten. The word Comma is derived from the Greek language, and tion to the notes at the bottom of the page. properly designates a section, or part struck off from a complete As these marks which have now been enumerated all have a sentence. In its usual acceptation, it signifies the point which meaning, and are employed for some special purpose, it is recommarks the smaller portions of a period. It therefore represents mended to the student never to pass by them without being the shortest pause, and consequently marks the least construc- assured that he understands what that purpose is. Correct and tive, or most dependent parts of a sentence.

tasteful reading can never be attained without a full appreciaThe word Colon is from the Greek, and signifies a member of tion of the meaning which the author intended to convey; and 1 sentence, and the Latin prefix semi means half. Hence, a that meaning is often to be ascertained by the arbitrary marks Semicolon is used for the purpose of pointing out those parts of employed by him for the purpose of giving definiteness to an a compound sentence which, although they each constitute a expression. At the same time, the student should consider these distinct proposition, have yet a dependence upon each other, or marks as his guide to the meaning only, not to the enunciation on some common clause. The Colon is used to divide a sentence of a sentence. Correct delivery must be left to the guidance of into two or more parts, which, although the sense be complete taste and judgment otherwise acquired. in cach, are not independent. The Colon is also used in In many excellent selections for lessons in reading, the pieces chanting, to indicate the division of a verse.

have been arranged in regular order, according to the nature of The word Period is derived from the Greek, and means a their respective subjects, under the heads of Narrative, Descripcircuit or well-rounded sentence. Hence, when the circuit of the tive, Didactic, Argumentative, and Pathetic pieces, Publio senze is completed, with all its relations, the mark bearing this Speeches, Promiscuous pieces, the Eloquence of the Bar, of the name is used to denote this completion.

Pulpit, and of the Forum. The Dash is only once used in the Bible, where it is employed By Narrative pieces are meant those pieces only which con23 an ellipsis (Exod. xxxii. 32).

tain a simple narration or story. Descriptive pieces are those The word Interrogation is derived from the Latin, and means in which something is described, chiefly from nature. Didactic a question. Hence this mark is put at the end of a question. pieces are those designed to convey some particular kind of

The word Exclamation is from the same language, and means instruction, whether moral, religious, or scientific. Argumentae passionate utterance. Hence the mark so called is put at the tive pieces are those in which some truth is designed to be end of such utterances.

proved in an agreeable manner. Pathetio pieces are those by The word Parenthesis, derived from the Greek language, means which the feelings of pity, love, admiration, and other passions, an insertion. A sentence, clause, or phrase, inserted between are excited. Promiscuous pieces are those which do not fall the parts of another sentence for the purpose of explanation, or exclusively under any of the classes which have been enumerated, of calling particular attention, is properly called a parenthesis. or which consist of a mixture of those classes. The Eloquence

It is to be remarked, however, that the name parenthesis of the Bar consists of speeches (or pleas as they are technically belongs only to the sentence inserted between brackets or crotchets, called) made by distinguished lawyers in the courts of justice in and not to those marks themselves.

favour of or against a supposed criminal. The Eloquence of the The word Hyphen is derived from the Greek language, and Pulpit consists of sermons or discourses delivered on religious signifies under one, that is, together; and is used to imply that occasions. The Eloquence of the Forum consists in the speeches, the letters or syllables between which it is placed are to be addresses, orations, etc., addressed to political or promiscuous taken together as one word.

assemblies. The hyphen, when placed over a vowel, to indicate the long To many, this information may seem superfluous or puerile. sound of the vowel, is called the Macron, from the Greek, signify. But as these lessons are designed for the young and the un

learned, it must not be forgotten that their sources of informaThe mark called a Breve, indicating the short sound of the tion are few, and that they will not always take the pains to vowel, is from the Latin, signifying short.

inform themselves of the meaning of words, even when they are The word Ellipsis, also from the Greek, means an omission, familiar to their eyes in capital letters, and in the running titles and properly refers to the words, members, or sentences which of the books before them every day. It is often the case that are omitted, and not to the marks which indicate the mission. the teacher also, taking for granted that his papils are familiar

The word Apostrophe, also from the Greek, signifies the turning with the meaning of words so often presented to their eyes, alcay, or the omission of one letter or more. The word apos- neglects to question them on the subject; and in riper years it trophe, as here used, must not be confounded with the same becomes a matter of surprise to the pupil himself that, in early Ford as the name of a rhetorical figure.

life, words which he had heard sounded almost every day at The word Diæresis is also from the Greek, and signifies the school presented no idea to his mind beyond that of an unmeantaking apart, or the separation of the vowels, which would other- ing or rather an unintelligible sound. wise be pronounced as one syllable.

The object of all education is not so much to fill the mind The term Accent is derived from the Latin language, and with knowledge as to strengthen its powers and enlarge its implies the tone of the voice with which a word or syllable' is to capacity. Those exercises, therefore, are always most

beneficial be pronounced.

in education which tend most effectually to produce this result. The word Section, derived also from the Latin, signifies a There is, perhaps, no branch of study connected with popular cutting, or a division. The character which denotes a section education which, when properly pursued, is more highly subserseems to be composed of es, and to be an abbreviation of the vient to this end than the study of correct and tasteful reading,

ing long.

as an art. It necessarily involves a complete knowledge of the cise also the power of classification, while studying a reading subject to be read, the relation and dependencies of the lesson (which should always be studied previous to practising phrases, clauses, and members of the sentences, the proper it), to ascertain ander which of the above-mentioned classes meaning of the words employed, and the connection between whether narrative, descriptive, didactic, etc.—the piece he is the sentences themselves. This cannot be acquired without a about to read belongs. The student who thus employs his vigorous employment of the perceptive powers, aided by those faculties cannot fail to feel a vigorous growth of intellect of comparison, of analysis, of reasoning, of judgment, of taste, springing up in his own mind, and will be amply compensated and of discrimination. Subordinate and auxiliary to the acqui. for his labour by a command over the stores of literature sition of this important art, the student is recommended to exer- not to be gained by any other method.

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mined, on which moral evil would otherwise rear her temple of

impurity. Look at the eye, nose, and mouth of the boy as he The above engraving is intended to illustrate the effects which is at school, or as he is located in one of the worst parts of different modes of life have upon the human countenance. London, and who does not perceive, from the very contour of the Even with the progress that has been made in the last few countenance, that his destiny will very much depend on the years, still we have around us far too many instances of the influences by which he may be surrounded ? In the one case, truth of this picture. Much has been said of the science of you see him pass into the higher and more polite circles of the phrenology ; but without depreciating the facts on which it is educated classes, yielding himself to all the softening, subduing, professedly based, we confess that we have a more profound refining elements of pure female society; and in the other, you faith in the doctrine of physiognomy. No one can deny that see him entirely lost to all sense of decency and self-respect, the “human face divine” has in it something expressive of rushing headlong into the scenes of dissipation, and surrendering that which enters into and constitutes the character of the himself to all the worst agencies of a wicked world. In the one man. It may come out in the eye, or the lip, or the nose, or instance you see him choosing his profession, and contemplating the general contour of the countenance; but there it is, and no a settlement in life-wedding himself to a virtuous, loving, and one can give himself to the closer and deeper study of this devoted woman, and in course of time becoming surrounded by subject without being able, more or less correctly, to read the a loving family; in the other you see the man emerging from the mysterious symbols of human character and destiny.

scenes of brutal intoxication to plunge into deeper, darker vices, Carefully examine the above engraving. Look at the head till his conscience is oppressed with guilt and misery, and life and face of the child represented in the first figure. Who can becomes a burden, from which he perhaps seeks relief in suicide; divine what that young intelligence will become in the future of or it may be that his conduct renders him obnoxious to law, his life? Is there anything in his features to indicate that he and he comes to a premature death. If he be spared this will act a conspicuous part on the great wide stage of this fate, he comes to beggary, and goes down to the grave unworld? Or is he to sink to the lowest depths in the scale of lamented and unwept. How different this from the career intelligent being ? Even in the outlines of the infant counte- of the man whose happiest days are spent in the bosom of his nance there may be the index of the future man. These out- loving family, and who grows old amid the most genial influences, lines will become more marked and definite in the boy amid honoured, revered, beloved ; who sees his children's children the studies and pursuits of the school. The period of boyhood unto the third or fourth generation, who goes down to his is one of wondrous development; and if this were but carefully last resting-place amid the prayers and tears of those he loved, watched, the foundation might in many cases be laid for the and whose dying moments are cheered by the hope of a happy erection of a true manly nobility—and that might be under. reunion in a world where life is perfect and joy complete.

that the problem of how to make a serviceable eye is a diffiANIMAL PHYSIOLOGY.-I.

cult one. THE EYE,

The analogy of the mirror, however, must not lead the reader

to suppose that a plane surface, sensitive to light, would be conThe eye is the instrument by which the mind becomes ac- scious of distinct images, or that it would see objects as we. quainted with external and distant objects by means of the light, by the aid of the eye, see them reflected on its surface. For which is one of the most subtle and delicate forces in nature, distinct vision, it is necessary that many divergent rays proceedand needs a correspondingly delicate and complicated organ to ing from each point in an object should be collected together appreciate its effects.

again in a point, and that point must lie exactly on the retinan Without inquiring into the nature of light, it is sufficient for or sentient mirror. Thus, the instrument known as a camera, our subject that we know

which has a lens set into the some of its constant qualities,

side of a box, and a surface at or laws, as they have been

the other side to receive the called.

image, is a more perfect simile In its simplest condition

for an eye. light travels in straight lines

We will now describe the in all directions, from its

structure of one of the most Bource; hence, when we see

perfect instruments for taking a luminous body, we know the

note of the impression prodirection in which it lies, be

duced by light with which we cause it must lie in the line of

are acquainted — the human the ray which reaches us.

eye. When & ray of light thus

The human eye is globular; travelling in a straight lino

differing, however, from a perstrikes upon the surface of any

fect sphere in some slight but object, it is affected in some

important particulars. The of the following ways accord.

thick, tough capsule, which ing to the nature of the object

maintains the shape of the eye, and of its surface :

and contains all the other parts 1st. It may be destroyed, as

necessary to perfect vision, is far as visual effects are con

about one inch from front to cerned, partially or wholly.

back, and a little more from 2nd. It may penetrate the

side to side and from top to substance of the body, being

bottom. This is called the more or less bent as it traverses

sclerotic, or hard coat of the the surface. This occurs when

eye. This hard coat, which the body is transparent.

forms the eyeball, differs from 3rd. It may glance off and

a true sphere also, in that its pursue & different direction

1. VERTICAL SECTION OF THE HUMAN EYE IN ITS SOCKET. front part, occupying about outside the object upon which

one-sixth of its circumference it strikes.

a, sclerotic or hard coat of the eye; b, choroid; e, retina or nervous (in section), bulges forward far The first effect is called ab. mirror; d, membrane holding the vitreous humour; e, vitreous more than it would do if it sorption; the second, refrao- humour; f, cornea ; 9, aqueous chamber and humour ; h, crystalline were only a part of the larger tion; and the third, reflection.

Jens; i i, iris; k k, ligament to hold lens; l, meibomian glands; m m, globe ; and this part differs Reflected light concerns us muscles to wield the eye; n, muscle to lift the eye-lid.

from the other in texture also, most. The eye occupies itself

fo: while it is equally strong with reflected rays. If light were incapable of being reflected, and tough, and even harder, it is purely transparent, while the the sun would appear as a sharply-defined dazzling orb in a rest of the eyeball is opaque and white. This front clear por: pitch-dark universe, and eyes would be of no use ; for though tion, which is let into the hinder part as a bay-window is put poets tell as so, not even the eagle spends its time in so profit- l into the wall of a room, or as an old-fashioned watch-glass is less and injurious an

set into the rim of employment as gaz.

the watch-case, is ing on the sun.

called the cornea, or Now, as reflected

horny structure. Its light travels in

greater projection or straight lines from

convexity is not a the object upon

matter of accident, which it is reflected,

but highly importa it is to the eye, in

ant, for if it were all respects, the

not so, no near obsame as thongh that

ject could be seen object were itself 2. DIAGRAM SHOWING HOW OBJECTS ARE IMPRINTED ON THE RETINA.

distinctly. luminous. As light

Lining the inner proceeds from all parts of an object, and travels in straight | surface of the sclerotio is a thin membrane, which supports linea, we have only to let the rays fall upon some surface which in its outer layers the larger arteries and veins which carry shall receive them without derangement, to get an image which the blood to and from the front and inrer parts of the eye, will give the colour, form, and, by a little inferential reasoning, while it has on its inner surface a very thin pavement of the size and distance of the object.

flat, six-sided cells; each cell filled with black grains. The The first requisite in an eye, then, is a sentient mirror, which grains, and even the cells which contain them, are so small and shall receive the images of objects and feel them.

so closely set as to form what appears to any but a high magThis mirror must be of moderate and portable size, and well nifying power, a continuous thin black sheet, perfectly opaque. ander control, so that it can be turned about.

This membrane papers the inside of the eye as far forward as All mirrors are perishable and delicate articles, liable to frac- the place where the sclerotio joins the cornea, and is there cou.

but when we conceive of a mirror whose surface and nected firmly with this outer jacket by a strong ligament and backing, and even its very frame, must be made not of hard muscle. Before it reaches this point, however, it is puckered glass

, imperishable quicksilver, and durable wood, but of soft into somewhat irregular fore-and-aft folds. Beyond this point renewable tissues, and think how indispensable it is that it the choroid, as this membrane is called, is continued as a freely, abould be protected and kept in a state of repair, we must admit hanging curtain, shaped like a quoit, that is, ronnd and opaque



with a hole in the middlo of it, which is opposite the middle of too little, distinct images of near objectis are impossible. If the cornea, or window of the eye.

the crystalline lens is too dry, or too moist, it becomes clouded From the same circle of attachment, but internal to the with hard or soft cataract. If the pigment be not of sufficient curtain before-named, is suspended, or rather held, by a liga- quantity in the choroid, vision is interfered with ; and from this ment, a perfectly transparent body shaped like a lentil, that is, cause albinos, or persons whose hair and skin are deficient in with two conver but flattened surfaces. The quoit-like curtain colouring matter, are dazzled in ordinary daylight. is called the iris, and the disc the crystalline lens. The lens is Further, if the retina, or part of it fail, as it sometimes does, slung at some little distance from the cornea, leaving a chamber, from some cause too subtle to be found out, the object is seen which is filled with watery fluid, which bathes both sides of the only in part; thus, some persons have this peculiar affection of iris. Behind the lens, and occupying the larger part of the hollow half the retina, so that when they look directly at an object, of the eye, is a denser liquid, contained in a thin, perfectly. they only see the half of it. transparent membrane, which not only encircles it, but sends in The retina, perfect in all its other functions, may not dispartitions from its outer wall to divide the liquid into compart criminate colour. The writer once played a game at croquet ments, so that when the eye is cut into the humour does not with a gentleman, who disclosed his infirmity thus: Two balls run out, but seems to be of the consistence of clear jelly. Both were lying together one red, and the other green. He asked the liquid and capsule are so transparent that they are called which was his, and being told the red one, asked which red the hyaloid membrane and vitreous humour, or the glassy mem- one ? On another occasion the writer was looking at a brightlybrane and humour.

coloured geological map. A stranger who looked with him soon All the main parts of tho eye have now been described except showed that he was quite unaware that it was other than the the essential one for which all the others are made, namely, ordinary ordnance map. the retina : that wonderful stratum of nervous matter which These defects of vision call marked attention to the perfecreceives and transmits to the brain all luminous impressions, tion of the instrument of vision, when perfect, as it is in the glories of colour, the splendid imagery of the earth, and the most cases. soft radiance of the sky.

It would be difficult to determine whether the eyo were made The retina lies between the choroid and vitreous humour. for light, or light for the eye; but that the Creator of the one It lines the choroid as closely as that membrane lines tho was cognisant of all the wonderful qualities of the other, sclerotic, and so covers the whole back part of the eye.

admits of no doubt; and this goes far to prove that the Creator The retina (or sentient mirror), thin as it is, has been found of the one must have been the designer of the other. under the microscope to consist of many layers of diverse structare. Not to descend into great minuteness, it may be said to consist of an outer layer of cylindrical bodies, called, from their

LESSONS IN ENGLISH.-II. shape, rods and cones, which run perpendicularly to the surface of junction between retina and choroid. These bodies are the

SIMPLE PROPOSITIONS. instruments by which the rays are noted. It would seem that

Alfred reads. each rod or cone conveys but ono impression, so that while the THESE two words form what is called a proposition; they forme image of an external object may be made very small on the a simple proposition. Proposition is a word of Latin origin, retina, and yet distinctly seen, because of the minuteness of signifying something that is put before you. As being somethese bodies, yet the image must cover a certain number of them thing that is put before you, it is a statement; it is a statement to be an image at all. In other words, if it only covered one of a fact or a thought; a statement of something in the mind, the impression would be that of a single point of light.

or something out of the mind. Here the statement is that Next comes the granular layer, the office of which is no further Alfred reads. Such a statement is also termed a sentence. known than that similar structures are found wherever impres- Sentence is also from the Latin, and signifies a form of words sions received by the senses are modified. The innermost layer comprising a thought or sentiment. These words, then-namely, consists of nerve-fibres, which convey the impressions in some sentence, proposition, and statement, have the same significa such way as the telegraph wires convey their messages. These tion; and they each denote an utterance, the utterance of a fact, all run to one point in the back part of the eyeball, a little on an idea, an emotion. Observe that both words are essential to the inner or nose side of the axis, and there pass through the the proposition. Take away Alfred, you then have reads; but choroid and sclerotic, which are pierced by a great many holes, reads is no proposition, for nothing is stated. Take away reads, and are united behind into the optic nerve, and this runs to the you leave Alfred; but Alfred by itself says nothing, makes no brain, first, however, being joined by its fellow from the other statement, and therefore forms no proposition or sentence. The øye, and then separating from it again, having received some of two words must concur to make a proposition. If so, less than the strands of this nervous cord, and given up some of its own two words do not make a proposition; and a proposition or in return.

sentence may consist of not more than two words, Let us now trace the course of a number of rays reflected from In these simple statements you have in the germ the sub& single point in an object, before they reach the retina (see Fig. stance of the doctrine of sentences. If you understand what I 2). These rays as they come from a single point are, of course, have now said, you have laid the foundation for a thorough diverging. They strike, therefore, all over the surface of the acquaintance with language in general, and with the English cornea, and as they pass through it are gathered somewhat language in particular; for to a form of words similar in sim. together. They then pass the aqueous humour with a slightly plicity to that which stands at the head of this lesson is all altered course. The outer ones are cut off by the opaque iris, speech reducible; and that model presents the germ out of which but the central ones pass through the lens, which rapidly gathers are evolved the long and involved sentences of our old English them together, and they are then transmitted through the divines, and the full and lofty eloquence of Milton's immortal vitreous humour, all the time convorging until they meet at a essay on behalf of the liberty of the press. point exactly in or on the retina.

The sentence as it stands is what is called an affirmative In saying that they meet exactly on the retina, it is meant proposition ; that is, it affirms or declares something—it affirms that they will do so if the adjustment is perfect. If it be im. or declares that Alfred reads. The term affirmative is used in perfect, so that the rays unite in a point either before the retina, opposition to the term negative. Negative propositions are or would unite behind it if they could traverse the choroid, thé those in which something is denied. An affirmative may become image is blurred and indistinct.

a negative proposition by the introduction of the adverb not; The problem of how to get a distinct image, of course, is thus, Alfred reads not. In English it is more common to employ more difficult, when the points from which the light proceeds also the emphatic does, as Alfred does not read. You thus seo are numerous, as from any object of appreciabie form. To ob- that the words does (do, or dost, as may be required) and not tain this, the surface of the cornea, the hind and front face of convert an affirmative into a negative proposition. Sentences the lens, and the face of the retina, must all be of definite and in which

a question is asked we term interrogative; as, does regular curves, or the figure would be distorted. If the cornea Alfred read?' Here by the help of the emphatic form does, and bulges too much, the object can only be seen at a short dis- the inversion of the terms does and Alfred, we make an affirmative tance, and from this cause some persons have to lay their into an interrogative sentence. If into this last sentence we cheeks

upon the page before they can read print. If it buiges | introduce the negative not, we have an interrogative negative

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