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Thus, two things may stand in a certain relation to each other, in respect of their quantity, magnitude, shape, colour, strength, height, tc.; in which cases the subject of comparison is common to both, and belongs to them to a greater or less amount. Thus, when we say that one thing is larger, taller, thicker, smaller, darker, more beautiful, more lasting, more desirable, more formidable, more probable, &c., than another, we mean that each of the pairs in question having in common the quality referred to, the former has it in a greater degree than the latter. These, which might be called ratios of degree, differ altogether from the other class, which includes all those relations arising from the manner in which one term of the ratio has affected the other, or is necessarily connected with it, and not from any attribute which they possess in common. Thus, we may speak of the relation of God and man, of the relations of men as members of the same political society or of different political societies, of the relation of a bird to its egg, of a tree to its fruit, &c., in which instances some act done by one to the other party, or by both reciprocally, or some influence which one term has exercised over the other, is signified, and not any quality or attribute common to both. In some cases of the latter kind there are words which express each term of the ratio in respect of the relation; and, therefore, they mutually imply each other. Such are, for example, parent and child, debtor and creditor, agent and principal, lessor and lessee, &c. As in these cases it is impossible to conceive the one without conceiving the other term, the latter might be called ratios of implication, as distinguished from those ratios in which a comparison is made of qualities existing independently in the things compared. For example, there cannot be a husband without a wife, or subjects without a sovereign, nor is there any quality which a husband has, as husband, independent of the wife, or the sovereign as sovereign, independent of the subject; but although there cannot be a short man or a tall man without a man of middle size, yet the height of the short or tall man is an absolute quantity, and independent of the comparison. In the cases of a common property, or ratios of degree, there are words which denote the relation of one term to the other, as lowness, height, depth, and consequently imply both terms of the ratio; but there is no word which expresses the term of the ratio itself, as in the case of ratios of implication. (Locke 'On the Understanding,' ii. 25.) There are some words used to denote the state of one of the terms of a ratio of implication when the relation has been destroyed; thus, widow means an unmarried woman who was once a wife; orphan, a child whose father is dead, &c. Sometimes the terms denoting a relation are applied by anticipation before the ratio begins to exist; thus, a person is popularly called an heir in the ancestor's lifetime although nemo est heres viventis.

When two ratios are compared, that is, when it is affirmed that the relation of two things is like the relation of two other things, the two ratios together form an analogy, and each pair of the corresponding terms of the two ratios is analogous. Thus, the bark stands in a similar relation to a tree as the skin to an animal; and consequently the one bears an analogy to the other: so the feathers of a bird are analogous to the hair of a quadruped, the admiral of a fleet is analogous to the general of an army. Of this nature are all fables and parables, in which the circumstances of the person to whom the lesson is addressed are illustrated by a parallel case, that is, by supposing a relation similar to that in which he is placed. Thus the case of a man who affects to despise what is out of his reach is vividly pourtrayed by the fable of the Fox and the Grapes;' and so in other cases, the parables of Holy Writ are instances of a similar mode of instruction, only the examples are not, as in fables, chosen among irrational animals. The same is the principle of grammatical and etymological analogy; thus, if to give is conjugated I give, thou givest, he gives, to live would be conjugated I live, thou livest, he lives; the inflexions of the verbs standing in a like relation to each. So the verb prattle is derived from to prate, as hobble is from to hop; little is derived from the old word lite, as mychel or myckle from much, &c. Thus, kingly is to king, as royal to the French roy, and regal to the Latin rex, or rather to the root reg. The formation and development of language proceed almost exclusively on this principle.

From what has been said it is evident, 1, that in an analogy there must be two ratios, and consequently four terms or objects of comparison; and 2, that there is no connection between resemblance and analogy, and that things may be analogous without being similar, and similar without being analogous.

1. With regard to the first of these propositions, it should however be observed, that, although there must be four terms, it is not necessary that all the four terms should be different. If there was such a necessity, one of the chief uses of analogy, as an engine of argument and discovery of truth, would be destroyed. All that is required is, that there should be two distinct ratios of what terms those ratios may consist is indifferent. Thus in the case of brethren, the parents are in an analogous situation in respect of each brother: so the grandfather is to the son, as the son is to the grandson. In such cases as these, both the relations are known frequently, however, the relation in which one thing stands to another being known enables us to discover, with greater or less certainty, the relation which the same thing bears to something else, which is unknown. Thus the moral government of mankind by the Deity, in this world, furnishes a means of conjecturing his religious government, both in this world and the

next, independently of Divine revelation. So the past conduct or performances of a nation, a government, a minister, a general, a lawyer an architect, a painter, a poet, a racehorse, &c., afford materials for judging what will be their future conduct or performances under similar circumstances. It is to this most important use of analogy that Quintilian refers, when he says that its purpose is to discover what is unknown by what is known, to prove what is uncertain by what is certain.

2. Resemblance being the similarity of some sensible quality, as form, colour, taste, smell, or sound, it has evidently no connection with analogy; and if things analogous happen to resemble one another, their resemblance is a mere accident, independent of their analogy. Thus, two brothers may resemble each other; but they might equally resemble each other without being brothers, and would be equally brothers if they did not resemble each other. The confusion of analogy and resemblance is however of very frequent occurrence, and numerous examples of it might be cited. When Homer says that Apollo and Minerva sat, like birds, on the branches of a tree near the Scæan gate of Troy, he meant, as birds sit on the branches, so did the god and goddess: but Pope, and other translators, represent them as undergoing a change of form, and assuming the appearance of birds. The above example may serve to illustrate an error of frequent occurrence in the use of the argument from analogy. As, in the instance just cited, the similitude is extended beyond its proper limits, and it is supposed that because the two objects are like each other in one respect, they are like in all; so the analogy between two things is sometimes pressed beyond its just application, and is carried out of the bounds of the relation in virtue of which the comparison was made. Thus the injunction to be "as wise as serpents and harmless as doves," does not recommend to our imitation either the envenomed ferocity of the one animal, or the helpless timidity of the other. Two false analogies may be mentioned which at one time had a powerful influence on political discussions, nor are even now quite exploded, namely, that the existence of the human race, and the existence of nations, are analogous to the life of a single man. For some purposes these two relations might doubtless be compared; but when it is argued that a nation will pass through a series of changes corresponding to the childhood, manhood, and old age of a single human being, or that the early state of mankind was like the innocence and simplicity of an infant, the comparison is unwarrantably wrested out of the range of its proper application. The notion of the corruption of a nation by luxury appears to have had a like origin; for single individuals may be, and often are, depraved by a sudden change from poverty to riches; but the process by which a nation enriches itself, is a mark of habits very different from vicious indulgence and effeminate indolence.

All analogical comparisons are made by means of abstraction. A certain attribute belonging to each of two objects is considered separately from all the other attributes which those objects may possess, and a comparison is instituted between them in respect of that common attribute. Thus, the analogy between the skin of an animal and the bark of a tree arises from our leaving out of our consideration all those circumstances in which they differ, such as their colour, consistency, animation, sensibility, &c., and paying attention only to the use of each, as the outward covering, in one case, of the body and limbs of the organised being, and in the other as the outward covering of the woody matter of the tree. It is by a like process of abstraction that an extended and vague meaning is given to many general terms, particularly those belonging to the moral sciences; and in this manner they are applied to objects to which they are only analogous, and which they do not properly designate. Thus a law, in its original and strict sense, is a general command of one rational being to another: but as one of the effects of such a command is to produce a uniformity of conduct in the person or persons to whom the command is addressed, the word has been transferred to inanimate objects in which there is a uniformity of phenomena; and although there is no command received, no command given, and no intelligence to work upon, we yet speak of the laws which regulate the motion of matter, the succession of the seasons, the diffusion of heat and light, and other physical appearances which follow in a constant relation of cause to effect. In this case the proper characteristics of a law being neglected, one of its relations is alone considered; and hence the analogical application just mentioned. When such an application is made, not from a vague or inaccurate use of language, but from a desire to add beauty or energy to the expression by the transfer of words, this transfer and sometimes the transferred word itself, is called a metaphor. Thus, when Shakspere represents Macbeth as saying of Duncan that

"His virtues

Will plead like angels, trumpet-tongued, against
The deep damnation of his taking off,"

he means that Duncan's virtues will arrest the public attention as forcibly as the sound of trumpets. The analogy is obtained by referring the two objects compared to the general class of things which instantly attract universal notice.

The word proportion properly signifies an analogy of quantities or magnitudes, as a proportion of numbers, lines, surfaces, &c. In popular usage however proportion is commonly made synonymous with ratio,

as when we speak of the proportion of deaths to births, the proportion of wages to profits, the proportion of convictions to commitments, &c. Sometimes also it is used for portion, as when we speak of a large proportion, a small proportion, a fair proportion; in this case however, a ratio is meant, as the part is considered as bearing a certain relation to the whole.

(On the subject of Analogy see Aristotle's Poetic, c. 21; Rhetoric, b. ii. c. 2; Hist. An. i. c. 1; Coplestone in the Appendix to Whately's Rhetoric; Whately's Rhet., part i, c. 2, s. 6; Mill's System of Logic, cap. iii. s. 12.)

ANALYSIS, a Greek word, signifying literally the act of unloosing or untying; its opposite is synthesis, which is the act of putting together. The modern meaning of the term analysis is the process by which facts, results, or reasonings are separated into their simple and component parts, or by means of which a simple truth is obtained when given in a more complicated form; so that, in its most general sense, the greatest part of human knowledge consists in the results of analysis. It is, however, for the most part applied in a more particular manner to the methods employed in those branches of inquiry, which most strikingly exhibit direct analysis; namely, mathematics and natural philosophy, particularly chemistry. By a very incorrect misnomer, algebra, the differential calculus, &c., have been called by the general name of analysis, in opposition, not to synthesis, but to geometry, in which latter science synthetical methods are most usually applied. This perversion of the term prevails on the Continent to such an extent, that it must always be taken for granted, that' analyse' stands for the algebraical branches of pure mathematics. In this sense it is again subdivided into algebraical analysis' and 'infinitesimal analysis,' the latter including the fluxional or differential calculus. And by 'geometrical analysis' is frequently understood the application of algebra to geometry. It must, however, be remarked, that the exact sciences have appropriated this word, simply because in these branches of knowledge the use of analysis has been made most conspicuous.

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and the equations (1.) and (2.) multiplied together, and the result divided by the common factor GD, gives

AD X ECX BF = AE × BD x CF.. (3.) whence the relation required between the six lines is as follows: Let them be separated into two lots of three lines each, in such a way that no two lines which have a common extremity are both in the same lot; then the product of the first three will be equal to the product of the second three.

If instead of asking for the relation, if any exist, between the six lines, the equation (3.) had been given, and it had been required to detect whether it were true or false, the process would have been similar; and we should have found that the equation (3.) is true, and a necessary consequence of the proposition, that a line drawn parallel to one side of a triangle divides the other sides into proportional segments. The synthetical form of the preceding process differs from it much less on the paper than would be the case in the mind of a student, who had actually hit upon the solution in the progress of investigation. For, not being able to tell the various steps by which one of our readers would endeavour to arrive at the same conclusion, we are

obliged to prompt him with a right guess, and thereby give him only a synthetical description of that which was in our minds an analytical It only remains, therefore, to make the demonstration syn

process.

Confining ourselves to the primitive meaning of the term, it is obvious that all discovery must be entirely either the work of analysis or of accident; and that, therefore, geometrical analysis must be as old as geometry. Nevertheless, this does not appear from the earliest treatises.thetical in form, which, as will now be readily seen, will consist in The work of Euclid is strictly synthetical. Instead of taking the pro- stating the proposition to be proved, directing to draw co parallel to position asserted, and examining it by means of preceding propositions, DF, without giving any reason, and combining the steps of the preceding and in the mean time assuming it to be true, in order to ascertain demonstration. whether the results deduced from it agree or disagree with what has The geometrical analysis is generally ascribed to the school of Plato; been already proved,-Euclid first enunciates the point which he means but, in reality, as we have already observed, must be of a date as early to establish, and then proceeds to put together the considerations by as geometrical reasoning itself. The use of PORISMS, or problems [see which it is demonstrated, leaving the earner nothing to do but to also Locr] admitting an indefinite number of solutions, the establishjudge of the truth or falsehood of each argument as it arises, without ment of the properties of the CONIC SECTIONS, and the various efforts taking into consideration the methods by which the arguments them-made for the DUPLICATION of the cube and the TRISECTION of the angle, selves were first obtained. This is the natural and proper method of all of which were the work of the school already mentioned, most teaching what has already been discovered, for its own sake; not only certainly increased the power of the analyst, that is, made the means because it neglects to introduce difficult and embarrassing considera- of discovery more obvious and more successful; but there is nothing tions, and allows of the subject being broken up into portions which in the methods which entitles them to the exclusive appellation of are easily learnt at one time, but because there is, in reality, no per- geometrical analysis. fectly general and certain method of analysis which can be made obvious to the beginner. In attempting the analysis of a new problem, though the discoverer will naturally first try those methods which have been successful in preceding cases, he has no means of assuring himself beforehand which will be successful. The chemist is similarly circumstanced. Let a new substance, or one supposed to be such, be presented to him, from which he is required to find out whether it is already known, or if not, of what it is composed. No effective analysis can commence without requiring the results of all his previous knowledge; for he must have some method of recognising cach and every substance with which he is acquainted, previously to pronouncing whether or not that under consideration is one of them. He must then proceed to trials of that substance with various others, and nothing but the sagacity which arises from previous experience can direct him in his choice of the methods to be employed. No general rules of analysis can be laid down: that is, no processes which must end in the discovery of the component parts required. The same observations may be made on mathematical analysis. We give a geometrical instance, with its result, and the synthetical form of the proposition arising out of it.

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The sides of a triangle ABC are cut in D, E, and F, by a straight line. Six segments are thus formed, AD and DB, whose sum is the side AB; AE and EC, whose sum is the side AC; and BF and Fc, whose difference is the side BC. It is required to investigate the relation which exists between these six segments, if there be any relation. Some relations will be thrown out of the question upon the slightest consideration: the sum of the six lines is not the same in every

The peculiar distinction between algebra and geometry is, that the analytical method is pursued in the former from the commencement. The solution of a problem consists in inquiring into the consequences of the solution supposed to be found, by introducing at every step some known truth, such as will produce a more simple consequence, and thus reasoning backwards, so to speak, until at last the answer itself is directly produced in numbers, which was before implicitly involved in the conditions of the problem. The methods are more general than in geometry, that is, a larger number of problems may be solved by each process. The same observations apply still more strongly to the higher parts of algebra, and the differential calculus.

The solution of equations of the first four degrees, and the approximation to that of all higher degrees, render the analytical solution of a vast number of common problems a matter of certainty. The solution of differential equations, where that can be done, is an additional step of even a more important character. Within the last century, mathe matical analysis has made considerable approaches to a state which enables us to determine, almost immediately, whether a problem can be solved by such means as we possess, or not; no small advantage, when it is considered how much time was previously wasted in the attempt to attain results which have since been shown to be impossible. ANALYSIS, CHEMICAL. [CHEMICAL ANALYSIS.] ANALYSIS, EUDIOMETRIC. [GASOMETRIC ANALYSIS.] ANAMERTA or ANAMIRTA, the name of a genus of plants belonging to the natural order Menispermacea, to which the plant yielding the Cocculus Indicus of commerce is now referred. It has the following characters: flowers dioecious, calyx of six sepals in a double series with two-close pressed bracteoles, corolla none; stamens on separate flowers united into a central column, dilated at the apex; anthers numerous, covering the whole globose apex of the column. The flowers with pistils are not known, but the fruit is a one- to three-celled drupe. The seed is globose, deeply excavated at the hilum, albumen fleshy, cotyledon very thin, diverging. The plant which yields the berries of commerce is the only species of this genus. It is a strong climbing shrub, and is met with on the coasts of Malabar and the Eastern Islands. It is called Anamirta Cocculus; it possesses a powerful bitter poisonous principle, and is used for external applications only.

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ANAMORPHO'SIS (avauópowσis, a remodelling or change of form'), is such a representation of an object that, except when viewed from a particular point directly, or in a cylindrical mirror, or through a polyhedral lens, it will appear to be distorted, or disconnected, or to be a view of something very different from the original object. Such representations are only made for the amusement of young persons, and therefore a very brief explanation of them may suffice; but the art of forming them has been treated at length in the Thaumaturgus Opticus' of Niceron, and in the 'Perspectiva Horaria' of Maignan. Distorted figures which are to appear, when viewed directly from a given point, in the just proportions which they have in an original drawing or print, may be easily traced in the following manner. the original be covered with a network of squares, and imagine it to stand vertically on paper laid on a table, the eye being in a given position in its front; then draw lines through the ground line, in the directions in which planes passing through the eye and the vertical lines drawn on in the original would cut the paper, and other lines parallel to the ground line at places where planes passing through the eye and the horizontal lines on the original would cut the paper. If within the trapezoidal areas thus formed the parts of the original figure which fall in the corresponding squares be drawn, the figure thus traced will be the distorted figure required; and, when viewed from the assumed place of the eye, it will evidently appear exactly as, to an eye in the same point, the original would appear if it were placed in a vertical position with the base on the line which was drawn to represent it; that is, it will appear to be an exact copy of the original.

as, for instance, in the three middle syllables of the word anticipātion. The predominance of dactyles in English, and of anapæsts in French, forms one of the most marked distinctions between the musical character of the one language, and that of the other.

ANAPESTIC VERSE, a species of verse composed of a succession
of anapasts. Among the Greeks the anapastic verse was freely used
both in tragedy and comedy. Some forms of it occur very often in
Aristophanes. Both in tragedy and comedy, the anapastic verse
admits also dactyles and spondees. In English, only poems of the
lighter sort have been usually written in anapastic verse. Anstey's
'New Bath Guide' may be quoted as a well-known example. The
line is often reduced to eleven syllables, by the retrenchment of the
first, or the substitution at the beginning of an iambus instead of the
anapast. Thus, in the following lines from the work thus mentioned:
"For I'm told the discourses of persons refin'd
Are better than books for improving the mind;

But a great deal of judgment's requir'd in the skimming
The polite conversation of sensible women"

it will be observed, that the first foot of the second line consists only
of one short or unaccented syllable followed by a long; and a similar
retrenchment might be made of the commencing syllable of any of the
others, without spoiling its prosody.

ANARCHY properly means the entire absence of political government; the condition of a society or collection of human beings inhabiting the same country, who are not subject to a common sovereign. Every society of persons living in a state of nature (as it is termed) is in a state of anarchy; whether that state of nature should exist in a society which has never known political rule, as a horde of savages, or should arise in a political society in consequence of resistance on the part of the subjects to the sovereign, by which the person or persons in whom the sovereignty is lodged are forcibly deprived of that power. Such intervals are commonly of short duration; but after most revolutions, by which a violent change of government has been effected, there has been a short period during which there was no person or body of persons who exercised the executive or legislative sovereignty, that is to say, a period of anarchy.

Anarchy is sometimes used in a transferred or improper sense to signify the condition of a political society, in which, according to the writer or speaker, there has been an undue remissness or supineness of the sovereign, and especially of those who wield the executive sovereignty. In the former sense, anarchy means the state of a society in which there is no political government; in its second sense, it means the state of a political society in which there has been a deficient exercise of the sovereign power. As an insufficiency of government is cominon exaggeration, been used to signify the small degree, where it properly means the entire absence. [SOVEREIGNTY.]

A distorted representation of some object, which is to appear correct on being viewed from a given point, and by reflection from a cylindrical mirror whose curvature and position are also given, may be drawn on a plane by means of a perspective representation, as already described, or the squares drawn within a square circumscribing the original print or drawing. Thus a circular are being drawn with a radius equal to that of the base of the cylinder, to intersect, between the eye and the ground line, all the oblique lines drawn in forming that representation; let lines be drawn from the intersections, making respectively equal angles with tangents to the circle, so as to represent the reflections of those oblique lines; and on the reflected lines set distances from the circumference equal to the distances of the parallel lines in the former representation from the same points in the circum-likely to lead to no government at all, the term anarchy has, by a ference. Then curve lines connecting the points so determined will form, with the reflected lines, spaces within which the parts of the original figure are to be traced so as to correspond to those within the squares first drawn. This distorted tracing being laid horizontally on a table, and the mirror being set up vertically on the arc which represents its base, the reflected image will, to the eye, appear exactly similar to the original figure.

Distorted figures, which are to be seen corrected when viewed through a polyhedral lens or multiplying glass, may be traced mechanically thus:-let the multiplying glass be placed in a tube, like the eye-piece of a telescope, at a distance from the end to which the eye is to be applied rather greater than the focal length of the glass, and let a very small aperture be formed in the cover at that end: then, on placing a lamp or candle before the aperture, the rays of light passing through the faces of the lens will project, on a screen placed perpendicularly to its axis, at any convenient distance beyond the focus, a number of luminous spaces corresponding to the several faces of the lens, with intervals between them. In these luminous spaces, whose outlines should be traced with pencil before the light is removed, there must be drawn by hand parts of a landscape or figure, so that, on looking through the aperture, they shall seem to form a correct representation of the intended object.

The portions thus drawn, when viewed in any manner except through the aperture, will be unconnected; and the intervals may be filled up with any objects at pleasure, so that the whole may appear confused, or may represent something different from the original landscape or figure: then, on looking through the aperture, towards the screen, the intervals before mentioned, and the objects drawn on them, will be invisible; and there will appear only the representation of the object formed by the junction of the parts within the outlines first traced, that is, a correct copy of the original object.

ANASTATIC PRINTING. In the year 1841, the proprietors of the 'Athenæum' received from a correspondent at Berlin a reprint of four pages of a number of that journal which had been published in London a few weeks earlier. The copy was so perfect a fac-simile, that had it not come to hand under peculiar circumstances, it would have been taken for two leaves out of a sheet actually printed in London; the observable difference was, that the impression was somewhat lighter, and the body of ink less in quantity than usual. In reply to further inquiries, the correspondent at Berlin could only discover that the secret was said to be in the hands of a person at Erfurt. He had seen a fac-simile of an Arabic MS. of the 13th century; and another fac-simile of a leaf of a book printed in 1483-both such close copies as hardly to be detected from the originals, and both taken without injury to the originals. It was also stated that a prospectus was issued at Berlin, of a pirated edition of the 'Athenæum, to be produced in a similar way, and sold at a low price.

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In January 1845, the Athenæum' was enabled to announce that the inventor or discoverer of the method was a M. Baldermus, who had communicated the discovery to a person in London; and to convince the proprietors of that journal of the reality of the method, a page of L'Illustration,' French journal, was faithfully copied in a quarter of an hour. The method became known by the name of Anastatic printing; and many of the London journals directed attention to the subject. In the 'Art Union,' for February, 1845, pages 40 and 41 of the number were printed from zinc plates obtained by the Anastatic process. The compositors set-up' in the usual way, sufficient matter to fill two quarto pages of the work, leaving spaces for three wood-cuts, three drawings, and a few lines of writing in pen and ink, which were properly adjusted to the blanks left for them. ANAPEST, a foot in Greek and Latin metre, consisting of two All were alike copied or transferred to the zinc plates, and then printed short syllables followed by a long, It was sometimes called Anti-from-several thousand copies being taken. The impressions were dactylus, as being the opposite of the dactyle, which consists of a long syllable followed by two short. Assuming accent in English to be the same thing with quantity in Greek and Latin, the word temporal would be an example of a dactyle, and the word superádd of an anapæst. From the tendency of English enunciation to carry back the accent towards the beginning of polysyllables, there are not many single words which make anapæsts in our language. But the foot frequently results from the union of two or more words: as in Do you hear, Let älōne; and sometimes it is found in part of a single word;

fainter and less distinct than those from the original types, but were unquestionably remarkable.

Professor Faraday explained the rationale of the Anastatic process in 1845, at the Royal Institution. The process depends on a few known properties of the articles employed. 1st. Water attracts water; oil attracts oil; but each repels the other. 2nd. Metals are much more easily wetted with oil than with water; but they will readily be moistened by a weak solution of gum. 3rd. The power of wetting metals with water is greatly increased by the addition of phosphatic

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ANASTOMOSIS:

acid. 4th. A part of the ink of any newly-printed book can be readily
transferred by pressure to any smooth surface beneath; if, for
example, a corner of a newspaper be fixed on a white sheet of paper,
and then pressed or rubbed with a paper knife, the letters will be dis-
tinctly seen in reverse on the paper; and indeed every one knows that if
a book be bound too soon after the printing, the pages become disfigured
by the setting off or transfer of the ink upon the opposite pages. From
these data the rules for the process are derived. The printed paper,
whether letter-press or engraving, is first moistened with dilute acid,
and then pressed with considerable force by a roller on a perfectly
clean surface of zinc; by which means every part of the sheet of paper
is brought into contact with the plate of zinc. The acid, with which
the unprinted part of the paper is saturated, etches the metal, while
the printed portion sets off on it, so that the zinc surface presents a
reverse copy of the work. The zinc plate, thus prepared, is washed
with a weak solution of gum in weak phosphatic acid; this liquid is
attracted by the etched surface, which it freely wets, while it is
repelled by the oil of the ink in which the writing or drawing on the
plate is traced. A leathern roller, covered with ink, is then passed
over the plate, when a converse effect ensues; the repulsion between
the oil, ink, and watery surface over which the roller passes, prevents
any soiling of the unfigured parts of the zine plate; while the attraction
between oil and oil causes the ink to be distributed over the printed
When
portions. In this condition the anastatic plate is complete, and impres-
sions are pulled from it by the common lithographic process.
it is required to apply the anastatic process to very old originals, which
do not set off their ink on pressure, the page or print is first soaked in
a solution of potash, and then in a solution of tartaric acid: by which
is produced a perfect diffusion of minute crystals of bi-tartrate of
potash through the texture of the unprinted part of the paper. As
this salt resists oil, the ink-roller may now be passed over the sur-
face without transferring any of its contents, except to the printed
parts. The tartrate is then washed out of the paper, and the ope-
ration is proceeded with as before, commencing with the moistening
by nitric acid.

When these interesting details became publicly known, it was soon
ascertained that the so-called anastatic printing was little more than
an extension of processes known long before in England. Mr. Jobbins,
a lithographic printer, took copies of printed pages by a process ana-
logous to that of anastatic printing, as far back as the year 1840.
Mr. Cocks, of Falmouth, writing to the 'Mechanics Magazine,' said,
"In the year 1836 I introduced a process for the transferring of
copper-plate engravings (by the old masters), as well as letter-press
printing, &c., to stone, zinc, tin, pewter, type-metal, fusible-metal,
lead, copper, glass, &c., and had impressions taken from each; but the
original subjects were destroyed by the chemical agents used. Since
that time I have succeeded in transferring prints and letter-press
without even soiling the originals, fixing the same on metal, wood, or
paper, and printing from the form any number of copies. The process
is so faithful in its operation, that the finest line of the etching needle
is preserved."

In 1848 Mr. Strickland and Mr. Delamotte instituted experiments with a view to ascertain how far the anastatic process would be available as a substitute for lithography. They succeeded in transferring or printing from drawings made on paper with lithographic chalk; within an hour after the drawing was made, a perfect anastatic fac simile was produced, hardly to be distinguished from it. The chief difficulty here seems to be the production of a kind of paper which shall possess a surface similar to lithographic stone. A mode has been devised of imparting to India paper a clear sharp granular surface, well fitted for the purpose as far as regards surface; but it is almost too tender in substance. Mr. Strickland found that metallic paper, used for metallic pencils, had the required surface. For fine subjects copied in this way, it is essential that the lithographic chalk be of a hard quality, and cut to a fine point.

In 1853, a particular application of lithography was introduced into England from Germany, where it had been patented by M. Sigl. It was a process of machine-printing in lithography, for cheap commerIn preparing the cial purposes rather than for matters of fine art. plates, a mode of transfer was adopted somewhat analogous to that of anastatic printing. A reference to LITHOGRAPHY will, indeed, show that this analogy extends much farther.

An officer of the United States Survey department, devised a mode of transfer, nearly allied in character to the above, for the printing of maps and charts. An impression from an engraved copper-plate is taken with ordinary ink, on a peculiar kind of paper coated with a fatty substance; and it is then transferred to a lithographic stone, which can be prepared and used in the customary way.

Soon after the introduction of the anastatic process, much alarm was expressed in the commercial world lest it should facilitate the forgery of bank-notes, bank post-bills, cheques, bills of exchange, and other monetary documents. The uneasiness appeared to be not wholly groundless; but the interval between 1841 and 1859 has passed over without any serious realisation of the fears entertained. The transfer of impression is remarkable; but it could not escape the keen scrutiny of persons accustomed to watch for fraud in written or printed documents.

ANASTOM'OSIS, from avà, through, and σrópa, a mouth, signifies

ANATOMY ACT.

Now so numerous

All the

the communication of blood-vessels with each other by the opening of
the one into the other. The blood-vessels are the tubes by which the
different parts of the body are supplied with nourishment. If the
But the blood-vessels are soft com-
blood-vessels destined to nourish a part be obstructed so that it cannot
receive a due supply of blood, that part must necessarily die, or, as it
is technically termed, mortify.
pressible tubes, liable, by innumerable circumstances, to have their
sides brought so closely into contact as to prevent the flow of a single
particle of blood through them. In order to prevent the consequences
that would result to the system from the operation of causes thus
tending to impede the circulation, provision is made for the freest
possible communication between the main trunks of the blood-vessels
arteries of the body spring from one great trunk (AORTA) which issues
and their branches, and between one branch and another.
from the heart, and which passes from the heart through the chest,
into the abdomen, where it divides into large branches which supply
the lower extremities. In this course this vessel gives off innumerable
branches, which supply different parts of the body, and these branches
form innumerable unions with other branches which proceed from the
are these
main trunk of the artery. All the branches which form such com-
munications are called anastomosing branches, and this union of branch
with branch is termed anastomosis.
anastomosing branches, and so competent are they to carry on the
or even in the chest, the lower extremities will receive a sufficient
circulation, that if the main trunk of the aorta be tied in the abdomen,
supply of blood to maintain their vitality through these collateral or
anastomosing branches. The knowledge of this fact enables the modern
surgeon to perform with ease and safety operations which the surgeon
of former times would have pronounced impossible. Anastomosis is
branches. When the communication is direct between two large
of two kinds, that between large trunks, and that between small
trunks, there is no difficulty in conceiving that the circulation may
readily go on though one of the trunks be obstructed, because the
to nourish the part to which it is destined. But when a limb is sup-
trunk which remains open may transmit a sufficient quantity of blood
plied by one large artery only, and when that is obstructed, how does
What is the conse-
the limb receive a sufficient quantity of blood to support it? Suppose
there is an obstacle to the free passage of the blood through its usual
channel, namely, the main artery of the limb.
quence?-the blood is driven in greater quantity, and with greater
force into those branches which spring from the main artery above the
seat of the obstruction. These branches, in consequence of receiving
a greater influx of blood than usual, gradually enlarge in diameter, and
transmit through them a proportionally larger quantity of blood. At
the same time, the more minute branches, which anastomose with the
branches given off below the obstruction, are in like manner dilated
At first the circulation is in this manner carried on
of the limb.
and admit a correspondingly free passage of blood to the inferior part
through a congeries of minute anastomising arteries, but in a short
these increase in size, the smaller vessels gradually collapse, and thus
time a few of these channels become more enlarged than the rest: as
ultimately a few large communications constitute permanent channels
through which the blood is transmitted to the parts which it is destined
to supply. Such is the beautiful provision established in every part
of the body to secure to it a due supply of blood, if any obstacle should
ANA'THEMA, a Greek word, properly signifying, a thing set apart
obstruct the course of this vital fluid through its accustomed channel.
and devoted. Among the Greeks a piece of armour or anything else
which was offered to the gods, and placed in a temple, was called an
àvábnua (anathéma), or offering. Tripods, votive tablets with inscrip-
tions, such as may be seen in the Elgin collection of the British
Museum, belong to the class of anathemata. But the dedication or
or, according to Pagan notions, to the infernal as well as to the celestial
setting apart might be to the powers of evil as well as to those of good,
gods. Hence the word came, in one of its applications, to signify
much the same thing with the word accursed. It is thus that it is
1 Corinthians xvi. 22, with the added form of the original maran-atha,
principally used in the Old and New Testaments, where it appears, in
said to mean in Syriac, the Lord will come,' and is supposed to allude
to the third and principal excommunication among the Jews. In this
sense the form anáthema (àváleμa) was employed, and not anathéma,
though both are really the same word. In the decrees of popes and
councils, also, a common form of expression is, whosoever shall do, or
not do, or believe, or not believe, a particular act or dogma, 'let him
be anathema,' that is, let him be held excommunicated, separated from
the society of the faithful, and branded with the curse of the church.
On the other hand, a heretic, when he renounced his errors and was
received into the bosom of the church, was accustomed to declare his
In English we more fre-
heresy anathema,' or a thing accursed.
quently use the term anathema in the sense of the curse or severe
denunciation itself than for the object of the curse; as when we speak
of the church directing its anathema against any particular opinion.
ANATOMY ACT. Before the passing of 2 & 3 Will. IV. c. 75, on
the 1st of August, 1832, the medical profession was placed in a situa
tion both anomalous and discreditable to the intelligence of the country.
The law rendered it illegal for the medical practitioner or teacher of
anatomy to possess any human body for the purposes of dissection,
save that of murderers executed pursuant to the sentence of a court of

justice, whilst it made him liable to punishment for ignorance of his profession; and while the charters of the medical colleges enforced the duty of teaching anatomy by dissection, the law rendered such a course impracticable. But as the interests of society require anatomy to be taught, the laws were violated, and a new class of offenders and new crimes sprung up as a consequence of legislation being inconsistent with social wants. By making anatomical dissection part of the penalty for crime, the strong prejudices which existed respecting dissection were magnified tenfold. This custom existed in England for about three centuries, having commenced early in the 16th century, when it was ordered that the bodies of four criminals should be assigned annually to the corporation of barber-surgeons. The 2 & 3 Will. IV. c. 75, repealed § 4, 9 Geo. IV. c. 31, which empowered the court, when it saw fit, to direct the body of a person convicted of murder to be dissected after execution. Bodies are now obtained for anatomical purposes under the following regulations, enacted in 2 & 3 Will. IV. c. 75, which is entitled 'An Act for regulating Schools of Anatomy.' The preamble of this Act recites that the legal supply of human bodies for anatomical examinations was insufficient, and that in order further to supply human bodies for such purposes various crimes were committed, and lately murder, for the sole object of selling the bodies of the persons so murdered. The Act then empowers the principal secretary of state, and the chief secretary for Ireland, to grant a licence to practise anatomy to any member or fellow of any college of physicians or surgeons, or to any graduate or licentiate in medicine, or to any person lawfully qualified to practise medicine, or to any professor or teacher of anatomy, medicine, or surgery; or to any student attending any school of anatomy, on application countersigned by two justices of the place where the applicant resides, certifying that to their knowledge or belief such person is about to carry on the practice of anatomy. Notice is to be given of the place where it is intended to examine bodies anatomically one week at least before the first receipt or possession of a body. The secretary of state appoints inspectors of places where anatomical examinations are carried on, and they make a quarterly return of every deceased person's body removed to each place in their district where anatomy is practised, distinguishing the sex, and the name and age. Executors and others (not being undertakers, &c.) may permit the body of a deceased person, lawfully in their possession, to undergo anatomical examination, unless, to the knowledge of such executors or others, such person shall have expressed his desire, either in writing or verbally, during the illness whereof he died, that his body might not undergo such examination; and unless the surviving husband or wife, or any known relative of the deceased person, shall require the body to be interred without. Although a person may have directed his body after death to be examined anatomically, yet if any surviving relative objects, the body is to be interred without undergoing such examination. When a body may be lawfully removed for anatomical examination, such removal is not to take place until forty-eight hours after death, nor until twenty-four hours' notice after death to the anatomical inspector of the district of the intended removal, such notice to be accompanied by a certificate of the cause of death, signed by the physician, surgeon, or apothecary who attended during the illness whereof the deceased person died; or if not so attended, the body is to be viewed by some physician, surgeon, or apothecary after death, and who shall not be concerned in examining the body after removal. Their certificate is to be delivered with the body to the party receiving the same for examination, who within twenty-four hours must transmit the certificate to the inspector of anatomy for the district, accompanied by a return stating at what day and hour, and from whom, the body was received, the date and place of death, the sex, and (as far as known) the name, age, and last abode of such person; and these particulars, with a copy of the certificate, are also to be entered in a book, which is to be produced whenever the inspector requires. The body on being removed is to be placed in a decent coffin or shell, and be removed therein; and the party receiving it is to provide for its interment after examination in consecrated ground, or in some public burial-ground of that religious persuasion to which the person whose body was removed belonged; and a certificate of the interment is to be transmitted to the inspector of anatomy for the district within six weeks after the body was received for examination. Offences against this Act may be punished with imprisonment for not less than three months, or a fine of not more than 50%.

The supply, under this Act, of the bodies of persons who die friendless in poorhouses and hospitals, and elsewhere, is said to be sufficient for the present wants of the teachers of anatomy; and the enormities which were formerly practised by 'resurrection-men' and 'burkers' have ceased.

ANCHOR. The anchor, which, under some form or other, must have been as ancient as ships of any magnitude, is mentioned by many Greek and Latin authors; by whom also its invention was ascribed to various persons. The first anchors were, most probably, what they now are among uncivilised nations, namely, large stones, or crooked pieces of wood loaded with heavy weights. The latter form is mostly used by the Chinese, and indeed upon our own coasts at the present day single heavy stones are used as anchors or "kitticks,,' by fishermen. The first anchors had but one fluke; another was afterwards added: but the anchor was yet without a stock, as appears from ancient monuments, and must have been very incomplete. This

ARTS AND SCI. DIV. VOL. I.

addition may, therefore, be considered as the last step towards the present form. Each ship then had several anchors; the chief one was called lepa, or sacred, and reserved for the last extremity,precisely as the largest and best is now used in emergencies under the name of "sheet anchor;" but the veneration paid to it has much declined since the custom of paying 51. to the master on letting it go was discontinued in the navy. For the purposes of the present article, we shall notice first the mechanical action of an anchor; then the mode of its manufacture; and lastly, the changes recently introduced in its form.

The technical parts of an anchor, which must be borne in memory, are the following:-The shank is the main or central shaft; the small is the end of the shank near the top; the throat near the bottom; the trend two-thirds down the length of the shank; the ring is at the extreme upper end; the stock branches out immediately beneath the ring; the arms branch out at the other end of the shank; the palms, or flukes, are flattish portions at the ends of the arms; the bill, or peak, is the extreme end of each palm; and the crown is the part farthest from the ring.

It may suffice at present to state that the difference between bower, sheet, stream, kedge, and spare anchors, is rather one of size than of construction. Referring, therefore, to the annexed cut for an illustration of the several parts of an anchor, we proceed to show its mode of action.

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When the anchor is let go from the ship's side, it will, on reaching the bottom of the sea, most commonly fall upon the crown and the end of the stock; because the stock moves through the water in the direction of its length with less resistance than in that of its breadth. From The longer this position the anchor must be turned or canted over. the stock, within the practical limits of stowage, the more certainly will the anchor turn properly; and, when hooked in the ground, the more powerfully will it resist any effort to overset it. Also, it is evident that the anchor will turn the more easily as the arm is shorter. In repairing old anchors, it is common to shorten the shank; in doing this, it is the custom also to shorten the stock in the same proportion. This, which is equivalent, in fact, to lengthening the arms, might, if carried to any extent, prevent the possibility of the anchor turning over, and therefore it appears that when the shank is shortened, the stock should remain unaltered. The amount of force required thus to overturn any given anchor might be found by calculation, or by actual trial; and it is remarked that the result of the former may be diminished by one-seventh when the anchor is under water.

The anchor being in the position of fig. 2, its weight, supposed to be collected at the centre of gravity, G (not including the stock), tends to force the fluke F into the ground; Fig. 2. and as this pressure on F will evidently be greater, as the vertical line Gg passes nearer to F c, this pressure is W. Ад (W. = the weight, exclusive of the stock). As soon as the cable pulls from a, it causes the fluke to catch or hook deeper, that is,

AF

G

F

it forces the fluke down; and the position of the fluke should be such as to form the angle most favourable for this purpose.

Suppose the arm CF imbedded, or the shank lying along the bottom, and the cable acting in the line CA with a tension t; then the pressure on the fluke taking place perpendicular to its surface, draw FI perpendicular to the nuke, and draw FP, tangent to the fluke, meeting

Y

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