stood, are the nominatives in all inflections of a verb; or it is the agent or patient in all finite or personal verbs. See ENGLISH LANGUAGE.

PERSONAL ACTION, in law, is an action levied directly and solely against the person; in opposition to a real or mixed action. See ACTION. PERSONAL GOODS or CHATTELS, in law, signifies any moveable thing belonging to a person, whether alive or dead. See CHATTELS.

PERSONATE, the fortieth order in Linnæus's Fragments of Natural Method, consisting of plants whose flowers are furnished with an irregular gaping or grinning petal, which in figure somewhat resembles the snout of an animal (see BOTANY, Index). Most of the genera of this order are arranged under the class and order didynamia angiospermia. The rest, although they cannot enter into that artificial class and order, for want of the classic character, the inequality of the stamina; yet, in a natural method, which admits of greater latitude, may be arranged with those plants which they resemble in their habit and general appearance, and particularly in the circumstances expressed in that title.

PERSONIFICATION, PERSONIFYING, or PERSONALISING, the giving an inanimate being the figure, sentiments, and language of a person. See ORATORY. Dr. Blair, in his Lectures on Rhetoric, gives this account of personification. It is a figure the use of which is very extensive, and its foundation laid deep in human nature. At first view, and when considered abstractedly, it would appear to be a figure of the utmost boldness, and to border on the extravagant and ridiculous. For what can seem more remote from the tract of reasonable thought than to speak of stones and trees, and fields and rivers, as if they were living creatures, and to attribute to them thought and sensation, affections and actions? One might imagine this to be no more than childish conceit, which no person of taste could relish. In fact, however, the case is very different. No such ridiculous effect is produced

by personification when properly employed; a the contrary, it is found to be natural and agree able, nor is any very uncommon degree of pas sion required in order to make us relish it. All poetry, even in its most gentle and humble forms, abounds with it. From prose it is far from being excluded; nay, in common conversation, very frequent approaches are made to it. Wher we say, the ground thirsts for rain, or the earth smiles with plenty; when we speak of ambition's being restless, or a disease being deceitful; such expressions show the facility with which the mind can accommodate the properties of living creatures to things that are inanimate, or to abstract conceptions of its own forming.' The Doctor goes on to investigate the nature of personification at considerable length. And he add a very proper caution respecting the use of it in prose compositions, in which this figure require to be used with great moderation and delicacy. The same liberty is not allowed to the imagina tion there as in poetry. The same assistances cannot be obtained for raising passion to as proper height by the force of numbers and the glow of style. However, addresses to inanimate objects are not excluded from prose; but have their place only in the higher species of oratory. A public speaker may on some occasions very properly address religion or virtue; or his na tive country, or some city or province, which has suffered perhaps great calamities, or has been the scene of some memorable action. But we must remember that, as such addresses are among the highest efforts of eloquence, they should never be attempted unless by persons of more than ordinary genius: for if the orator fails in his design of moving our passions by them, he is sure of being laughed at. Of all frigid things, the most frigid are the awkward and unseasonable attempts sometimes made towards such kinds of personification, especially if they be long continued.'

Prior.

Faith for reason's glimmering light shall give Her immortal perspective. How richly were my noon-tide trances hung With gorgeous tapestries of pictured joys! Joy behind joy, in endless perspective!

Young.

PERSPECTIVE is a branch of the science of optics which teaches how to represent the objects of vision on a plane surface.

Vitruvius says that the first who wrote a treatise on this subject was Agathareus, a disciple of Aschylus, and that subsequently his principles were elucidated and improved by Democritus and Anaxagoras. None of these treatises of the ancients, however, have come down to modern times. It is to the revival of painting in Italy that we must trace the existing art; and it seems to have owed its reviviscence particularly to that branch of painting which was employed in the decorations of the theatres.

The Arabian optician Alhazen, who flourished about the year 1100. should not be omitted.

however, in our catalogue of writers. Roger Bacon cites his work, and treats himself on the subject with creditable accuracy.

The earliest writer whose rules of perspective survive is Peter del Borgo, an Italian, who died in 1443. He supposed objects to be placed beyond a transparent tablet, and endeavoured to trace the images which rays of light, emitted from them, would make upon it. What success he had in this attempt we know not, as his book on this subject has perished. It is, however, very much commended by the famous Ignatius Dante; and, upon the principles of Borgo, Albert Durer constructed a machine, by which he could trace the perspective appearance of objects. Balthazar Perussi studied the writings of Borgo, and endeavoured to make them more intelligible. To him we owe the discovery of points of distance, to which all lines that make an angle of 45° with the ground line are drawn.

Not long after, another Italian, Guido Ulbaldi, observed that all the lines that are parallel to one another, if they be inclined to the ground line, converge to some point in the horizontal line, and that through this point also a line drawn from the eye, parallel to them, will pass. These principles put together enabled him to make out a pretty complete theory of perspective.

His work was published at Pesaro in 1600, and may be said to have contained the fundamental principles of the system of Gravesande and Dr. Brook Taylor; the outline, in fact, of the only system worth the student's attention. For, while this is a science of the first importance to a painter, he is not, at the same time, to be too strictly confined to its rules. Nothing, indeed, should be permitted to tie up his hands or cramp his genius; on the contrary, he should be left fully at liberty to express his idea with one stroke of his pencil; and, as Fresnoy advises, let the compasses be rather in his eyes than in his hands;' in that way let him measure distinctly every object by comparison-the principal talent which he should own. If he is well acquainted with the principles of his art, he will not stop at the dry rules of geometry, while his fancy is sketching all the chief parts of his picture; but proceed with the whole, and, when the design is arranged, then correct all those portions which require it by the laws of perspective.

But while, on the one hand, we are anxious to guard the student against dwelling too much on the more mechanical parts of his interesting art, we must, on the other, strive to impress on his mind that a thorough knowledge and an undeviating attention to this important branch of it is not only eligible but indispensable. The study of it should, indeed, go hand in hand with that of anatomy, as not less fundamental

and necessary.

The contour of an object drawn upon paper or canvas represents nothing more than such an intersection of the visual rays sent from the extremities of it to the eye as would arise on a glass put in the place of the paper or canvas. Now, the situation of an object at the other side of a glass being given, the delineation of it in

of the eye on this side of the glass; in other words, on the rules of perspective.

To understand these, suppose a person at a window looks through an upright pane of glass at any object beyond it, and keeping his head steady, draws the figure of the object upon the glass with a black lead pencil, as if the point of the pencil touched the object itself; he would then have a true representation of the object in perspective as it appears to his eye.

To do this, let the glass be laid over with strong gum water, which, when dry, will be fit for drawing upon, and will retain the traces of the pencil; and then let the student look through a small hole in a thin plate of metal, fixed about a foot from the glass, between it and his eye, and keep his eye close to the hole; otherwise he might shift the position of his head, and consequently make a false delineation of the object.

After tracing out the figure of the object, he may go over it again with pen and ink; and, when that is dry, put a sheet of paper upon it, and trace it thereon with a pencil; then taking away the paper and laying it on a table, he may finish the picture by giving it the colors, lights, and shades, as he sees them in the object, of which he will now have a true resemblance.

To such as have a general knowledge of the principles of optics, this must be self-evident: for as vision is occasioned by pencils of rays coming in straight lines to the eye from every point of the visible object, it is plain that, by joining the points in the transparent plane, through which all those pencils respectively pass, an exact representation must be formed of the object as it appears to the eye in that particular position, and at that determined distance; and could pictures of things be always first drawn on transparent planes, this simple operation, with the principle on which it is founded, would comprise the whole theory and practice of perspective. As this, however, is far from being the case, rules must be deduced from the sciences of optics and geometry for drawing representations of visible objects on opaque planes; and the application of these rules constitutes what is properly called the art of perspective.

Before we lay down the further principles of this art, it is proper to observe, that when a person stands directly opposite to the middle of one end of a long avenue, which is straight and equally broad throughout, the sides thereof seem to approach nearer to each other in proportion as they are farther from his eye; or the angles, under which their different parts are seen become gradually less, according as the distance from his eye increases; and, if the avenue be very long, the sides of it at the farthest end seem to meet: and there an object that would cover the whole breadth of the avenue, and be of a height equal to that breadth, would appear only to be a mere point.

Having made these preliminary observations, we now proceed to

SECT. I.-DEFINITIONS OF THE TERMS USED IN PERSPECTIVE.

1. The horizontal line is that line supposed to

of the spectator; or rather, it is a line which separates the heaven from the earth, and which limits the sight. Thus A and B, plate PERSPECTIVE, fig. 1, are two pillars below the horizontal line C D, because the eye is elevated above them; in fig. 2 they are said to be equal with it; and in fig. 3 raised above it. Thus, according to the different points of view, the objects will be either higher or lower than the horizontal line.

2. The point of sight A, fig. 4, is that which makes the centrical ray on the horizontal line a b; or it is the point where all the other visual rays D, D, unite.

3. The points of distance C, C, fig. 4, are points set off in the horizontal line at equal distances on each side of the point of sight A.

4. And in the same figure B B represents the base line or fundamental line.

5. E E is the abridgment of the square, of which D, D, are the sides.

6. F, F, the diagonal lines which go to the points of distance C, C.

7. Accidental points are those where the objects end; these may be cast negligently, because neither drawn to the point of sight, nor to those of distance, but meeting each other in the horizontal line. For example, two pieces of square timber, G and H, fig. 5, make the points I, I, I, I, on the horizontal line; but go neither to the point of sight K, nor to the points of distance C, C; these accidental points serve likewise for casements, doors, windows, tables, chairs, &c.

8. The point of direct view, or of the front, is when we have the object directly before us; in which case it shows only the fore side; and, if below the horizon, a little of the top; but nothing of the sides, unless the object be polygonous.

9. The point of oblique view is when we see an object aside of us and as it were aslant, or with the corner of our eye; the eye, however, being all the while opposite to the point of sight; in which case we see the object laterally, and it presents to us two sides or faces. The practice is the same in the side points as in the front points; a point of sight, points of distance, &c., being laid down in the one as well as in the other. 10. Projection delineates objects in plano by means of right lines called rays, supposed to be drawn from every angle of the subject, to particular points. When the objects are angular, these rays necessarily form pyramids, having the plane or superficies whence they proceed for their basis; but, when drawn from or to circular objects, they form a cone.

11. Ichnography, or ichnographic projection, is described by right lines parallel among themselves and perpendicular to the horizon from every angle of every object, on a plane parallel to the horizon: the points where the perpendicular lines or rays cut that plane being joined by right lines. The figure projected on the horizontal plane is likewise called the plan or seat of that object on the ground plane. The points are the sites, or seats, of the angles of the object. The lines are the seats of the sides. By this we are to understand how the basis of figures represented as superstructures stand or are supported; and we are further enabled to judge of, indeed to measure, their several parts and their areas.

12. Orthography represents the vertical position and appearance of an object; and hence orthographic projection is called the elevation. When we see the front of a house represented, we give it that term; when the side, we denominate it the profile. If we suppose a house, or other object, to be divided by a plane passing perpendicularly through it in a line at right angles with the point, we call it the lateral section; but, if the plane pass in a direction parallel with the front, it is termed a longitudinal section. If the plane passes in neither of the former directions (not however deviating from the vertical), it is said to be an oblique section.

13. These afford us the means of laying down plans, of showing the parts and the manner in which the interiors of edifices are arranged, consequently are indispensable to the architect or surveyor, and indeed should be understood by every individual connected any way with de signing or building. Nor should the following be neglected; namely, scenography, which shows us how to direct the visual rays to every point or part of a picture; and stereography, which enables us to represent solids on a plane, from geometrical projection; whence their several dimensions, viz. length, breadth, and thickness, may all be represented, and correctly understood at sight.

14. An original object is that which becomes the subject of the picture, and is the parent of the design.

15. Original planes or lines are the surfaces of the objects to be drawn; or they are any lines of those surfaces; or they are the surfaces on which those objects stand.

16. Perspective plane is the picture itself, which is supposed to be a transparent plane, through which we view the objects represented thereon.

17. Vanishing planes are those points which are marked upon the picture by supposing lines to be drawn from the spectator's eye parallel to any original lines, and produced until they touch the picture.

18. Ground plane is the surface of the earth, or plane of the horizon, on which the picture is imagined to stand.

19. The ground line is that formed by the intersection of the picture in the ground plane. 20. Vanishing points are the points marked down in the picture by supposing lines to be drawn from the spectator's eye parallel to any original lines, and produced until they touch the picture.

21. The centre of a picture is that point on the perspective plane where a line drawn from the eye perpendicular to the picture would cut it; consequently it is that part of the picture which is nearest to the eye of the spectator.

22. The distance of the picture is that from the eye to the centre of the picture. The distance of a vanishing point is the distance from the eye of the spectator to that point where the converg ing lines meet, and, after gradually diminishing all the objects which come within their direction and proportion, are reduced so as, in fact, to terminate in nothing. All parallel lines have the same vanishing points; that is to say, all such as are, in building, parallel to each other,

when not represented precisely opposite to, and parallel with, the eye, will appear to converge towards some remote point, i. e. their vanishing point. Circles, when retiring in such manner, are represented by ellipses, proportioned to their distances: their dimensions in perspective are ascertained by enclosing them, or the nearest of them, where a regular succession is to be portrayed, within a square, which, being divided into any number of equal parts or chequers, will exhibit all the proportions of those more remote. 23. A bird's eye view is supposed to be taken from some elevated spot which commands a prospect nearly resembling the plane or ichnography of the places seen. Thus the view from a high tower, or from a mountain, whence the altitudes of the various objects on the plane below appear much diminished, gives nearly the same representation as is offered to a bird flying over them and hence the term. Some idea of this may be obtained by standing on any height, and observing how low those objects which are near thereto will appear when compared with those more distant; taking however the perspective diminution of the latter into consideration.

When a painter has formed a scene in his mind, and supposed, as is customary, that the principal figures of this scene lie close, or almost close, to the back of his canvas, he is, in the next place, to fix on some point on this side of the canvas from which he would choose his piece should be seen. But in choosing this point, which is called the point of sight, regard should be had to its situation to the right or left of the middle of the canvas; but, above all things, to its distance and height with respect to the lower edge of the canvas; which edge is called the base line, and is parallel with the horizontal line which passes through the eye. For by assuming the point of sight, and consequently the horizontal line, too low, the planes upon which the figures stand will appear a great deal too shallow; as, by assuming it too high, they will appear too steep, so as to render the piece far less light and airy than it ought to be. In like manner, if the point of sight is taken at too great a distance from the canvas, the figures will not admit of degradation enough to be seen with sufficient distinctness: and, if taken too near it, the degradation will be too quick and precipitate to have an agreeable effect. Thus, then, it is evident that no small attention is requisite in the choice of this point.

When a picture is to be placed on high, the point of sight should be assumed low, and vice versá: in order that the horizontal line of the picture may be, as near as possible, in the same horizontal plane with that of the spectator; for this disposition has a surprising effect. When a picture is to be placed very high, as, amongst many others, that of the Purification, by Paolo Veronese, it will be proper to assume the point of sight so low that it may lie quite under the picture, no part of whose ground is in that case to be visible; for, were the point of sight to be taken above the picture, the horizontal ground of it would appear sloping to the eye, and both figures and buildings as ready to tumble headforemost It is true, indeed, that there is seldom

a necessity for such extraordinary exactness; and that, unless in some particular cases, the point of sight had better be high rather than low: as a reason for which we may observe that, as we are more accustomed to behold people on the same plane with ourselves than either higher or lower, the figures of a piece must strike us most when standing on a plane nearly level with that on which we ourselves stand. To this it may be added that by placing the eye low, and greatly shortening the plane, the heels of the back figures will seem to bear against the heads of the foremost, so as to render the distance between them far less perceptible than it would otherwise be. The point of sight being fixed, according to the situation in which the picture is to be placed, the point of distance is next to be determined. In doing this a painter should carefully attend to three things: first, that the spectator may be able to take in, at one glance, the whole and every part of the composition; secondly, that he may see it distinctly; and, thirdly, that the degradation of the figures and other objects of the picture be sufficiently sen

sible.

SECT. II.-GENERAL RULES.

1. Let every line which in the object or geometrical figure is straight, perpendicular, or parallel to its base, be so also in its scenographic delineations, or in the description, in all its dimensions, such as it appears to the eye; and let the lines which in the object return at right angles from the fore right side, be drawn in like manner scenographically from the point of sight.

2. Let all straight lines which in the object return from the fore right side, run in a scenographic figure, into the horizontal line.

3. Let the object you intend to delineate, standing on the right hand, be placed also on the right hand of the point of sight; that on the left hand, on that hand of the same point; and that which is just before, in the middle of it.

4. Let those lines which, in the object, are equidistant from the returning line, be drawn in the scenographic figure from that poist found in the horizon.

5. In setting off the altitude of columns, pedestals, &c., measure the height from the base line upward in the front or fore right side; and a visual ray down that point in the front shall limit the altitude of the column, or pillar, all the way behind the front side, or orthographic appearance, even to the point of sight. This rule must be observed in all figures, as well where there is a front, or fore right side, as where there is none.

6. In delineating ovals, circles, arches, crosses, spirals, and cross arches, or any other figure in the roof of a room, first draw ichnographically, and so, with perpendiculars from the principal points thereof, carry it up to the ceiling, from which several points carry on the figure.

7. The centre in any scenographic regular figure is found by drawing cross lines from the opposite angles; for the point where the diagonals cross is the centre.

8. A ground plane of squares is alike, both above and below the horizontal line; only the

more it is distant either above or below the horizon, the squares will be so much the larger or wider.

9. In drawing a perspective figure where many lines come together, to direct your eye, draw the diagonals in red, the visual lines in black, the perpendiculars in green, or any other color different from that which you intend the figure shall be.

10. Having considered the height, distance, and position of the figure, and drawn it accordingly, with its side or angle against the base, raise perpendiculars from the several angles or designed points, from the figure to the base, and transfer the length of each perpendicular, from the place where it touches the base, to the base on the side opposite to the point of distance. Thus the diametrals to the perpendiculars in the base, by intersection with the diagonals drawn to the several transferred distances, will give the angles of the figures; and so lines drawn from one point to another will circumscribe the scenographic figure.

11. If in a landscape there be any standing waters, as rivers, ponds, &c., place the horizontal line level with the farthest sight or appearance of it.

12. If there be houses, churches, castles, towers, mountains, ruins, &c., in the landscape, consider their position, that you may find from what point in the horizontal lines to draw the front and sides of them in the picture.

13. In drawing objects at a great distance, observe the proportions, both in magnitude and distance, in the draught, which appear from the object to the eye.

14. In coloring and shadowing near objects, you must make the same colors and shades in your picture which you observe with your eye in the landscape; but, according as the distance becomes greater, the colors must be fainter, till at last they are gradually lost in a darkish sky-color. SECT. III-MECHANICAL ILLUSTRATIONS OF

DRAWING IN PERSPECTIVE.

1. Suppose LLD BA, fig. 6, plate PERSPECTIVE, a square piece of pavement, consisting of twenty-five pieces of marble, each a foot square: it must be measured exactly, and laid regularly down upon paper; and for the sake of a more distinct notion how every particular square will appear when you have a true perspective view of them, mark every other stone or marble black; or else number each of them as in the figure, which is divided into squares, every other one of which may be made to appear black, like the three at the bottom marked BC D: or 1, 2, 3, 4, answering to those which are marked in the perspective with the same numbers. To lay your plan in perspective, fix your point of sight as you observe in the figure; or more or less to the right or left; then draw the line K K parallel to, and at what distance you will from LL; and raise a line on each side from L to K, to form the figure you see, as a frame; then draw a line from the corner K, which is the point of distance, to the opposite corner L; and this line will regulate your work. Now draw lines from the squares of your plan to the point of sight, as exact as possible; and,

wherever your line of distance cuts those lines, draw lines parallel to the line L L, which will give you the squares in perspective, or the true figure of every square. Thus D, in the perspective plan, answers to B in the measured plan, and 1, 2, 3, and 4, answer to their corresponding squares in the same plan.

To raise either pillars, trees, houses, or any other bodies, according to their respective heights, at different distances and proportions, on the plan laid down, measure them out in perspective into squares of a foot or any other measure. Let one of these squares, 1, 4, in fig. 7, serve for the base of a pillar a foot thick. Mark the line LK, by the scale of the ground plan, into equal proportions or feet; a, b, c, d; which being so many feet high, and standing on the base, are uprights, not in perspective. Then draw a line, 45, parallel to 1 c. Join c and 5, and then you have the front of a body three feet high and one foot wide, which is the object you were to raise. From 4 draw a line with a black lead pencil, to the point of sight; and from 3 raise à line pa rallel to 4 5, till it touches the pencilled line passing from 5 to the point of sight, which will give you the side appearance of the column or body, as you will see it from the place where you stand.

a

Then, with a pencil, from c draw a line to the point of sight, which will determine the line 67 that bounds the perspective view of the column a-top. Afterwards from 2 raise a pencilled line parallel to a c or 1 c, till it touches the line drawn from c to the point of sight; then draw 67 parallel to c 5, and you will have the square of the top of the column as observed from A, which is supposed to be the place where you stand. It is to be observed that the line drawn from 2 to 6 is only imaginary, and in consequence is to be rubbed out, because, not being seen from the place where you stand, it must not appear the drawing. The same may be understood of the line drawn from 1 to 2; but it is necessary that they appear in the draught, as they direct you how to regulate the top of your column, and to place it with certainty upon its base.

Lastly, finish your column with "lines only, that is, from 1 to c, from 4 to 3, from 3 to 7, from c to 5, from 6 to 7, and from 1 to 4, whereby you will have the true representation of the column, as in fig. 8.

When this is done, you may erect other columns on the other squares in the same manner, observ ing to fling your shades all on one side, and being master of these few examples, which will cost very little trouble, you will find the principle of them apply to various objects.

For the construction of a camera obscura, 1. Darken the room EF, fig. 10, leaving only an aperture open in the window at V, on the side I'K, facing the prospect A B C D. 2. In this aper ture fit a lens, either plano-convex, or convex on both sides. 3. At a due distance, to be determined by experience, spread a paper or white cloth, unless there be a white wall; then on this, GH, the desired objects ABCD will be delineated invertedly. 4. If you would have them appear erect, place a concave lens between the centre and the focus of the first lens, or receive the image on a plane speculum inclined to the