Rees's Cyclopædia,' article EQUATORIAL). The lower part or stand rests on three foot-screws, and needs no description. The upper part is moveable on a cross axis AA, on which it is balanced; and when the polar axis is set at the proper inclination by the latitude semicircle B, the clamp c retains it there. The polar axis consists of an outer tube, DD, forming one piece with the horizontal axis above-mentioned, and of an interior axis which turns freely within the tube as in a socket. This latter axis carries the hour circle, E E, the verniers, FF, being fixed to the tube. The clamp and tangent screw of the hour-circle are partially seen at G G. The upper plate H is fixed on the inner axis, and revolves with it. Two pieces, II, rise from this plate, and carry the collars within which the cross or transit axis, KK, works. The declination circle, LL, and telescope, M M, are fixed to the extremities of the transit axis, the telescope being outside the collar. The declination clamp and tangent screw are seen at N N; the verniers are on the other side. These are attached to the support which rises from the plate H. Two levels are fixed on the lower part of the stand at oo, but they are only to be used for approximate adjustment. A delicate swing level, P, is hung from the transit axis, and a second level, Q, is fixed to the declination circle. The telescope has a micrometer, B, carrying wires for measuring small differences of decli

nation.

It is evident to those who know Fraunhofer's construction, that it is identical with the upper part of this universal equatorial. The suspension and motion of the polar axis and hour circle are the same as in the equatorial made by Troughton for the University of Coimbra. The position of the telescope is that of Megnié and Nairne.

the foot-screws rest.

The rules we have already given will enable any one to adjust the universal equatorial; but if the direction of the meridian be known, it is a simpler plan to adjust the instrument as an altitude and azimuth circle, which it becomes when the polar axis is vertical, and then by inclining the polar axis to the latitude of the place, it becomes an equatorial. There is no provision in the instrument itself for moving the polar axis in azimuth. The whole must be turned bodily, and for this purpose some preparation should be made in the stand on which The following references will be useful to the reader. A clock for carrying an equatorial, constructed by Messrs. Troughton and Simms, is described in the Abstracts of the Proceedings of the Royal Astronomical Society,' vol. iii., No. 6, with a wood-cut. This would probably act somewhat more steadily with a horizontal fly-wheel upon the vertical axis, but its performance is very good. An account of the slipping piece and the wire micrometer to be applied to the equatorial for observing double stars, with directions for their use, is given in the appendix to the Companion to the Maps of the Stars published by the Society for the Diffusion of Useful Knowledge,' 1836. For the mode of using the equatorial as a measuring circle, see the Cambridge and Greenwich Observations' for 1835 and 1836 of Halley's Comet, of the Solar Eclipse, and of the elongation of Jupiter's fourth Satellite; and for the corrections for refraction and parallax, the Introduction to the Greenwich Observations,' 1836, to which the reader should look if he wishes to know the best methods of making and reducing astronomical observations in general. Sir George Shuckburgh's Memoir' already referred to contains a valuable history of the instrument, though on consulting the authorities, we have been led occasionally to differ from him. A description | of Ramsden's refraction piece will be found at page 19 of Shuckburgh's paper, along with a collection of tables for computing the effects of refraction and parallax in R.A. and N.P.D. from the data which this ingenious appendage affords. Pearson's 'Practical Astronomy,' vol. ii. p. 517; Littrow, Memoirs of the Astronomical Society,' vol. ii. p. 45; Kriel, Mem. Ast. Society,' vol. iv. p. 495.

EQUERRIES (from the French écurie, a stable), the name given to certain officers of the Royal household in the department of the master of the horse, the first of whom is styled chief equerry and clerkmarshal. Their duties fall in rotation. When the sovereign rides abroad in state, an equerry attends. Officers of the same denomination form a part of the established households of the royal dukes, &c. EQUIANGULAR, EQUILATERAL, EQUI-CRURAL, EQUITANGENTIAL, &c. &c., a class of words beginning with EQUI, which, in composition forms an adjective expressive of the equality of two things spoken of. Thus equiangular means having equal angles, and so on. There is a certain liability to confusion, arising from mistaking between the application of such terms to different parts of the same figure and to different figures. Thus an equilateral triangle' must mean a triangle which has three sides all equal. But two triangles which are equilateral' may mean two triangles in which every side of the first has its equal among those of the second: the two not being separately equilateral. To avoid this, it is sometimes said that two triangles, such as have just been mentioned, are mutually equilateral.

EQUILIBRIUM (aqua libra), a state of rest produced by the mutual counteraction of two or more forces. The science of equilibrium is STATICS.

EQUIMULTIPLES, multiples in which equal numbers of times are taken. Thus seven times A and seven times B are equi-multiples of ▲ and B : a league and a yard are equimultiples of a mile and a foot. The student of the fifth book of Euclid should remember that this

word has no singular number: 7 A and 7 B are equimultiples, but 7 A
is not therefore to be called an equimultiple but one of the equi-
multiples. And the same of the word equal, whether separately or in
composition: A and B may be equal lines, but a is not an equal line.
Equality implies comparison of at least two things.
EQUINOCTIAL, a name given to the equator, from the night
being equal to the day when the sun is there.

EQUINOXES, the intersections of the equator and ecliptic; the vernal equinox being that in which the sun is when about to rise into the northern hemisphere; the autumnal equinox being that in which the sun is when about to sink in the southern hemisphere. These terms are relative: for the equinox which is vernal in our hemisphere is autumnal in the southern, and vice versâ.

12

EQUISE TIC ACID, Aconitic Acid (3HO, C, H, O,) an acid discovered by Bracconot in the equisetum fluviatile, in which it exists combined with magnesia.

This acid may be obtained in small colourless radiating crystals; its taste is sharp, and somewhat analogous to that of tartaric acid: it is unalterable in the air. When heated, it decomposes without subliming, and yields an oily uncrystallisable acid product. It dissolves readily both in alcohol and in water: the solution gives no precipitate either with lime or baryta water, but with acetate of lead and protonitrate of mercury it gives white curdy precipitates: it precipitates the persalts, but not protosalts of iron.

With potash and soda it yields deliquescent uncrystallisable salts; with ammonia, a crystallisable salt. With oxide of zinc, with lime, and magnesia, it forms uncrystallisable transparent compounds, which are unalterable in the air. [ACONITIC ACID; CITRIC ACID.]

EQUITES (horsemen), the name of an order in the Roman state. Their origin, according to the old tradition, was this:-Romulus having divided his subjects into three tribes, chose from each one hundred young men whom he destined to serve on horseback and act as his body-guard; this body of cavalry was called the celeres, and afterwards the equites. (Dionys., ii. 13.) Niebuhr supposes ('Hist. of Rome,') that whereas patres and patricii were titles of honour for individuals, celeres was the name of the whole class as distinguished from the rest of the nation. The three centuries of the celeres were called by the same names as the three tribes of the patricians, namely, Ramnes, Tities, and Luceres. Their tribunes are spoken of as a college of priests (Dionys., ii. 64), and it appears that the tribes of the patricians had also tribunes (Dionys., ii. 7). Moreover, when it is said that Tarquinius Priscus made three new centuries, which he added to the former three, and that the whole went under the name of the Sex Suffragia, or the six equestrian centuries, we cannot doubt that the alteration which he introduced was a constitutional and not merely a military one; that in fact the centuries which he formed were, like the original three, tribes of houses; that his innovation was nothing but an extension of the political division of the inhabitants of Rome under Romulus. (Niebuhr, "Hist. of Rome.") When Servius Tullius established the comitia of the centuries, he received the sex suffragia, which included all the patricians, into his first class; and to them he added twelve other equestrian centuries, made up of the richest of the plebeian order. (Niebuhr.) The ancient writers appear to have laboured under some great confusion with regard to this arrangement. Livy (i. 43) makes a proper distinction between the twelve equestrian centuries created by Servius and the six which existed before; but when he states (i. 36) that the cavalry in the reign of Tarquinius Priscus amounted to 1800, he appears to be antedating the origin of the eighteen equestrian centuries which formed part of the constitution of Servius. To the establishment of the comitia centuriata the creation of a body of equites, as a distinct order, seems to be due. The plan of Servius was, to a certain extent, identical with that of Solon. The object of both legislators was to break down the limits to which the old aristocracy was confined, and to set up an order of wealth by the side of the order of birth: not, however, that when a person could produce his 400,000 sesterces, he became ipso facto a knight, as was the case in after times. (Hor. "Ep." i. 1, 57.) According to the Servian constitution, good birth or the sanction of the censors was necessary for gaining a place in the equestrian order. (Polyb., vi. 20; Zonaras, vii. 19.) When Cicero says ("De Republica," ii. 20) that Tarquinius established the equestrian order on the same footing as that on which it stood in his own time, and also attributes to the same king the assigning of money to the equites for the purchase and keep of their horses, he is evidently inconsistent. In Tarquin's time, that is, before there was any plebeian order, it was natural enough that the poorer patricians, who were obliged to serve on horseback, just as the 'Ins at Athens, who were a poorer class than the Pentakosiomedimnoi, (Plut., "Sol." c. 18.) should be furnished with the means for doing so. But the case was different with the equites after the establishment of an order of wealth. A man might then be of equestrian rank, and yet have no horse assigned to him; thus, on the one hand, we find at the time of the siege of Veii a number of equites serving on horseback at their own expense (Liv., v. 7); and, on the contrary, L. Tarquitius, who was a patrician, was obliged to serve on foot from his poverty. (Liv., iii. 27.) From this it appears probable that a certain sum was fixed which it was not necessary for every eques to have, but the possessor of which was obliged to serve on horseback at his own expense if no horse could be given him by the public, and that those

939

EQUITY.

whose fortune fell short of this were obliged to serve in the infantry
under the same circumstances.

The lieutenant of the dictator was called "the chief of the equites"
(Magister Equitum); and although in later times he was appointed to
this office by the dictator himself, it is probable, as Niebuhr conjec-
tures (i., p. 559), that he was originally elected by the twelve centuries
of Plebeian equites just as the dictator, or Magister Populi, was by the
Sex Suffragia, in other words, by the Populus or Patricians.

revenues.

With regard to the functions of the equites, besides their military
duties, they had to act as judices or jurymen under the Sempronian
law under the Servilian law the judices were chosen from the senate
as well as from the equites: by the Glaucian law the equites alone per-
formed the office, and so on by alternate changes till the law of Aurelius
Cotta (B.C. 70), by which the judices were chosen from the senators,
The equites also farmed the public
equites, and tribuni ærarii.
Those who were engaged in this business were called the
Publicani; and though Cicero, who was himself of the equestrian
order, speaks of these farmers as "the flower of the Roman equites, the
ornament of the state, the safeguard of the republic" (Pro Plancio,'9),
it appears that they were a set of detestable oppressors, who made
themselves odious in all the provinces by their avarice and rapacity.
The equites, as it may be inferred from what has been already said,
gradually lost the marks of their distinctive origin, and became, as they
were in the time of Cicero for instance, an ordo or class of persons as
distinguished from the senate and the plebs. They had particular
seats assigned to them in the circus and the theatre. The insignia of
their rank, in addition to the horse, were, a golden ring and the an-
gustus clavus, or narrow band, on their dress, as distinguished from the
latus clavus or broad band of the senators: the two last insignia seem
to have remained after the former ceased to possess its original and
distinctive character.

EQUITY, according to the definition given by Aristotle, is "the
rectification of the law, when, by reason of its universality, it is
deficient; for this is the reason that all things are not determined by
law, because it is impossible that a law should be enacted concerning
some things; so that there is need of a decree or decision; for of the
indefinite the rule also is indefinite: as among Lesbian builders the
rule is leaden, for the rule is altered to suit the figure of the stone,
and is not fixed, and so is a decree or decision to suit the circumstances."
Equity," says Blackstone, "in its
(Ethics, B. v. c. 01, Oxford trans.)
true and genuine meaning, is the soul and spirit of all law; positive
law is construed and rational law is made by it. In this respect,
equity is synonymous with justice; in that, to the true and sound
interpretation of the rule." According to Grotius, equity is the
correction of that wherein the law, by reason of its generality, is
deficient.

Until jurisprudence has become really a science based on settled
principles, some such jurisdiction as our earlier law-writers have
attributed to the courts of equity is necessary to the due adminis-
tration of justice; and it is probable that in England it deserved the
Equity
humorous description given by Selden in his 'Table Talk:
in law is the same that spirit is in religion, what every one pleases to
make it; sometimes they go according to conscience, sometimes
according to law, sometimes according to the rule of court. Equity is
a roguish thing; for law we have a measure, know what to trust to;
equity is according to the conscience of him that is chancellor, and as
that is larger or narrower, so is equity. It is all one as if they should
make the standard for the measure we call a foot a chancellor's foot;
what an uncertain measure would this be! One chancellor has a long
foot, another a short foot, a third an indifferent foot: it is the same
thing in the chancellor's conscience."

This uncertainty has however long ceased in that branch of our law
which is expressed by the term Equity, and, from successive decisions,
rules as strict and principles as fixed have been framed and established
in our courts of equity as in our courts of law. New cases, it is true,
may and do arise, but they are decided upon these ascertained rules
and principles, and not from the notions of the judge as to what may
be reasonable or just in the particular case before him. Nothing in
fact is more common than to hear the chancellor say, that whatever
may be his own opinion, he is bound by the authorities, that is, by
the decisions of his predecessors in office and those of the other judges
in equity; that he will not shake any settled rule concerning property,
&c., it being for the common good that these should be certain and
known, however ill-founded the first resolution may have been.
In its enlarged sense, equity answers precisely to the definition of
justice, or natural law (as it is called), as given in the Pandects'
(lib. i. tit. 1, 1, 10, 11); and it is remarkable that subsequent writers
on this so-called natural law, and also the authors of modern treatises
on the doctrine of equity, as administered in the English courts, have,
with scarcely any exception, cited the above passage from Aristotle as
a definition of equity in our peculiar sense of a separate jurisdiction.
But according to this general definition every court is a court of
equity, of which a familiar instance occurs in the construction of
statutes, which the judges of the courts of common law constantly
interpret according to the spirit, or, as it is called, the equity, not the
strict letter.

6

It is hardly possible to define equity as now administered in this country, or to make it intelligible otherwise than by a minute

EQUITY.

"It is no longer," administered in its restrained and qualified sense. enumeration of the matters cognisable in the courts in which it is says Sir James Mackintosh in his life of Sir Thomas More, "in the acceptation in which the word is used in English jurisprudence, to be confounded with that moral equity which generally corrects the unjust operation of law, and with which it seems to have been formed from usages and determinations which sometimes differ from synonymous in the days of Selden and Bacon. It is a part of laws what is called common law in its subjects, but chiefly varies from it in its mode of proof, of trial, and of relief."

In this country the remedies for the redress of wrongs and for the are administered in courts of law, and those which are administered in enforcement of rights are distinguished into two classes, those which courts of equity; the former are called legal rights and wrongs, the latter equitable. Equity jurisdiction may therefore properly be defined as that portion of remedial justice which is administered by a court of equity as distinguished from a court of law, from which a court of equity differs mainly in the subject matters of which it takes cogniCourts of common law in this country proceed by certain prescribed zance and in its mode of procedure and remedies. forms of action alone, and give relief only according to the particular exigency of such actions, by a general and unqualified judgment for a simple judgment for either party, without qualifications or conditions, the plaintiff or the defendant. There are many cases, however, in which or peculiar arrangements, will not do entire justice. Some modificaon one side, or the other, or perhaps on both; some qualifications or tions of the rights of both parties may be required; some restraints to the exercise of rights, or the redress of injuries. To accomplish conditions present or future, temporary or permanent, to be annexed according to their present constitution they can only adjudicate by a Such prescribed forms of such objects the courts of law in this country have no machinery: simple judgment between the parties. actions are not confined to our own system of laws; they were known in the civil law, and the party could apply them only to their original purposes. In other cases he had a special remedy. Courts of equity, however, are not so restrained; they adjudicate by decree pronounced upon a statement of his case by the plaintiff, and the answer of the if necessary, with the evidence of all parties, also given upon oath. defendant given in upon oath, and the evidence of witnesses, together, These decrees are so adjusted as to meet all the exigencies of the so as to suit it to mutual and adverse claims, and the real and subparticular case, and they vary, qualify, restrain, and model the remedy stantial rights of all the parties so far as such rights are acknowledged by the established rules of equity.

The courts of equity bring before them all the parties interested in the subject matter of the suit, and adjust the rights of all however numerous; whereas courts of law in this country are compelled by their constitution to limit their inquiry to the litigating parties, although other persons may be interested: that is, they give a complete remedy in damages or otherwise for the particular wrong in question as between the parties to the action, though such remedy is obviously in many cases an incomplete adjudication upon the general rights of the parties to the action, and fails altgether as to other persons, not parties to the action, who yet may be interested in the result or in the subject matter in dispute.

Perhaps the most general as well as the most precise description of a court of equity is the outline given by Mr. Justice Story in the Encyclopædia Americana,' which he afterwards filled up in his welldiction in cases where a plain, adequate, and complete remedy cannot The remedy must be plain, for known Treatise on Equity. It is this-that a court of equity has jurisbe had in the common law courts.

if it be doubtful and obscure at law, equity will assert a jurisdiction.
It must be adequate, for if at law it fall short of what the party is
entitled to, that founds a jurisdiction in equity; and it must be
complete, that is, it must attain the full end and justice of the case,
it must reach the whole mischief and secure the whole right of the
party present and future, otherwise equity will interpose and give
relief. The jurisdiction of a court of equity is sometimes concurrent
with the jurisdiction of the courts of law; sometimes assistant to it;
and sometimes exclusive. It exercises concurrent jurisdiction in cases
more efficient aid is required than a court of law can afford. In some
where the rights are purely of a legal nature, but where other and
grant it. For strict law comprehending established rules, and the
of these cases courts of law formerly refused all redress, but now will
jurisdiction of equity being called into action when the purposes of
justice rendered an exception to those rules necessary, successive
exceptions on the same grounds became the foundation of a general
principle, and could no longer be considered as a singular interposition.
Thus law and equity are in continual progression, and the former is
constantly gaining ground upon the latter. Every new and extra-
a great part of what is now strict law was formerly considered as
ordinary interposition is by length of time converted into an old rule;
equity, and the equitable decisions of this age will unavoidably be
ranked under the strict law of the next. (Prof. Millar's View of the
acquired at a time when there was no such redress at law, it is
English Government.') But the jurisdiction having been once justly
not now relinquished by the courts of equity.

The most common exercise of the concurrent jurisdiction is in

A court of equity is also assistant to the jurisdiction of the courts of law in cases where the latter have no like authority. It will remove legal impediments to the fair decision of a question depending at law, as by restraining a party from improperly setting up, at a trial, some title or claim which would prevent the fair decision of the question in dispute; by compelling him to discover, upon his own oath, facts which are material to the right of the other party, but which a court of law cannot compel him to disclose; by perpetuating, that is, by taking and keeping in its custody, the testimony of witnesses, which is in danger of being lost before the matter can be tried; and by pro-ledge of the different modes in which such questions of fact are put viding for the safety of property in dispute pending litigation. It will also counteract and control fraudulent judgments, by restraining the parties from insisting upon them.

It frequently happens that, during the progress of the suit, from the discovery of new matter, the deaths and marriages of parties, and other causes, the pleadings become defective, and in these cases it is necessary to bring the new matter, or parties becoming interested, before the court. This is done by means of further statements, which are now introduced by way of amendments to the bill, or by obtaining leave of the court to revive a suit which has abated, proceedings which recent legislation has rendered very simple and rapid. Formerly the same thing was done by fresh bills, called supplemental bills, bills of In most of our colonies the governor is invested with the jurisdic-revivor, or bills of revivor and supplement, according to the nature of tion of chancellor; but in some of the greatest importance where a the defect which they were intended to supply. judicial establishment of some magnitude is maintained, the chief or supreme court is invested with the chancery jurisdiction.