Chapter IV: CYSTOPHORIDA (Cystonectae, Haeckel). With a very large (9)

HYPOCAUST (Gr. [Greek: hypokauston: hypo], beneath, and [Greek: kauein], to burn), the term given to the chamber formed under the floors of the Roman baths, through which the hot air from the furnace passed, sometimes to a single flue, as in the case of the _tepidarium_, but in the _calidarium_ and sweating-room to a series of flues placed side by side forming the lining of the walls. The floor of the hot-air chamber consisted of tiles, 2 ft. square, laid on a bed of concrete; on this a series of dwarf piers 2 ft. high were built of 8-in. square tiles placed about 16 in. apart, which carried the floor of the hall or room; this floor was formed of a bed of concrete covered with layers of pounded bricks and marble cement, on which the marble pavement in slabs or tesserae was laid. In colder countries, as for instance in Germany and England, the living rooms were all heated in a similar way, and round Trèves (Trier) both systems have been found in two or three Roman villas, with the one flue for the ordinary rooms and several wall flues for the hot baths. In England these hypocausts are found in every Roman settlement, and the chief interest in these is centred in the magnificent mosaic pavements with which the principal rooms were laid. Many of the pavements found in London and elsewhere have been preserved in the British or the Guildhall museums; and in some of the provincial towns, such as Leicester and Lincoln, they remain _in situ_ many feet below the present level of the town.

HYPOCHONDRIASIS (synonyms--"the spleen," "the vapours"), a medical term (from [Greek: to hypochondrion, ta hypochondria], the soft part of the body immediately under the [Greek: chondros] or cartilage of the breast-bone) given by the ancients, and indeed by physicians down to the time of William Cullen, to diseases or derangements of one or more of the abdominal viscera. Cullen (_Clinical Lectures,_ 1777) classified it amongst nervous diseases, and Jean Pierre Falret (1794-1870) more fully described it as a morbid condition of the nervous system characterized by depression of feeling and false beliefs as to an impaired state of the health. The subjects of hypochondriasis are for the most part members of families in which hereditary predisposition to degradation of the nervous system is strong, or those who have suffered from morbid influences affecting this system during the earlier years of life. It may be dependent on depressing disease affecting the general system, but under such circumstances it is generally so complicated with the symptoms of hysteria as to render differentiation difficult (see HYSTERIA). Hypochondriasis is often handed down from one generation to another in its individual form, but it is also not unfrequently to be met with in an individual as the sole manifestation in him of a family tendency to insanity. In its most common form it is manifested by simple false belief as to the state of the health, the intellect being otherwise unaffected. We may instance the "vapourish" woman or the "splenetic" as terms society has applied to its milder manifestations. Such persons are constantly asserting a weak state of health although no palpable cause can be discovered. In its more definite phases pain or uneasy sensations are referred by the patient to some particular region, generally the abdomen, the heart or the head. That these are subjective is apparent from the fact that the general health is good: all the functions of the various systems are duly performed; the patient eats and sleeps well; and, when any circumstance temporarily overrides the false belief, he is happy and comfortable. No appeal to the reason is of any avail, and the hypochondriac idea so dominates his existence as to render him unable to perform the ordinary duties of life. In its most aggravated form hypochondriasis amounts to actual insanity, delusions arising as to the existence of living creatures in the intestines or brain, or to the effect that the body is materially changed; e.g. into glass, wood, &c. The symptoms of this condition may be remittent; they may even disappear for years, and only return on the advent of some exciting cause. Suicide is occasionally committed in order to escape from the constant misery. Recovery can only be looked for by placing the patient under such morally hygienic conditions as may help to turn his mind to other matters. (See also NEUROPATHOLOGY.)

HYPOCRISY, pretence, or false assumption of a high character, especially in regard to religious belief or practice. The Greek [Greek: hypokrisis], from which the word is derived through the Old French, meant primarily the acting of a part on the stage, from [Greek: hypokrinesthai], to give an answer, to speak dialogue, play a part on the stage, hence to practice dissimulation.

HYPOSTASIS, in theology, a term frequently occurring in the Trinitarian controversies of the 4th and 5th centuries. According to Irenaeus (i. 5, 4) it was introduced into theology by Gnostic writers, and in earliest ecclesiastical usage appears, as among the Stoics, to have been synonymous with [Greek: ousia]. Thus Dionysius of Rome (cf. Routh, _Rel. Sacr._ iii. 373) condemns the attempt to sever the Godhead into three separate _hypostases_ and three deities, and the Nicene Creed in the anathemas speaks of [Greek: ex heteras hypostaseôs ê ousias]. Alongside, however, of this persistent interchange there was a desire to distinguish between the terms, and to confine [Greek: hypostasis] to the Divine _persons_. This tendency arose in Alexandria, and its progress may be seen in comparing the early and later writings of Athanasius. That writer, in view of the Arian trouble, felt that it was better to speak of [Greek: ousia] as "the common undifferentiated substance of Deity," and [Greek: hypostasis] as "Deity existing in a personal mode, the substance of Deity with certain special properties" ([Greek: ousia meta tinôn idiômatôn]). At the council of Alexandria in 362 the phrase [Greek: treis hypostaseis] was permitted, and the work of this council was supplemented by Basil, Gregory of Nazianzus and Gregory of Nyssa in the formula [Greek: mia ousia, treis hypostaseis] or [Greek: mia ousia en trisin hypostasesin].

The results arrived at by these Cappadocian fathers were stated in a
later age by John of Damascus (_De orth. fid._ iii. 6), quoted in R.
L. Ottley, _The Doctrine of the Incarnation_, ii. 257.

HYPOSTYLE, in architecture, the term applied to a hall, the flat ceiling of which is supported by columns, as in the Hall of Columns at Karnak. In this case the columns flanking the central avenue are of greater height than those of the side aisles, and this admits of openings in the wall above the smaller columns, through which light is admitted over the aisle roof, through clerestory windows.

HYPOSULPHITE OF SODA, the name originally given to the substance known in chemistry as sodium thiosulphate, Na2S2O3; the earlier name is still commonly used, especially by photographers, who employ this chemical as a fixer. In systematic chemistry, sodium hyposulphite is a salt of hyposulphurous acid, to which Schutzenberger gave the formula H2SO2, but which Bernthsen showed to be H2S2O4. (See SULPHUR.)

HYPOTHEC (Lat. _hypotheca_, Gr. [Greek: hypothêkê]), in Roman law, the most advanced form of the contract of pledge. A specific thing may be given absolutely to a creditor on the understanding that it is to be given back when the creditor's debt is paid; or the property in the thing may be assigned to the creditor while the debtor is allowed to remain in possession, the creditor as owner being able to take possession if his debt is not discharged. Here we have the kind of security known as pledge and mortgage respectively. In the _hypotheca_, the property does not pass to the creditor, nor does he get possession, but he acquires a preferential right to have his debt paid out of the hypothecated property; that is, he can sell it and pay himself out of the proceeds, or in default of a purchaser he can become the owner himself. The name and the principle have passed into the law of Scotland, which distinguishes between conventional hypothecs, as _bottomry_ and _respondentia_, and tacit hypothecs established by law. Of the latter the most important is the landlord's hypothec for rent (corresponding to distress in the law of England), which extends over the produce of the land and the cattle and sheep fed on it, and over stock and horses used in husbandry. The law of agricultural hypothec long caused much discontent in Scotland; its operation was restricted by the Hypothec Amendment (Scotland) Act 1867, and finally by the Hypothec Abolition (Scotland) Act 1880 it was enacted that the "landlord's right of hypothec for the rent of land, including the rent of any buildings thereon, exceeding two acres in extent, let for agriculture or pasture, shall cease and determine." By the same act and by the Agricultural Holdings (Scotland) Act 1883 other rights and remedies for rent, where the right of hypothec had ceased, were given to the landlord.

HYPOTHESIS (from Gr. [Greek: hypotithenai], to put under; cf. Lat. _suppositio_, from _sub-ponere_), in ordinary language, an explanation, supposition or assumption, which is put forward in the absence of ascertained facts or causes. Both in ordinary life and in the acquisition of scientific knowledge hypothesis is all-important. A detective's work consists largely in forming and testing hypothesis. If an astronomer is confronted by some phenomenon which has no obvious explanation he may postulate some set of conditions which from his general knowledge of the subject would or might give rise to the phenomenon in question; he then tests his hypothesis until he discovers whether it does or does not conflict with the facts. An example of this process is that of the discovery of the planet Neptune: certain perturbations of the orbit of Uranus had been observed, and it was seen that these could be explained on the hypothesis of the existence of a then unknown planet, and this hypothesis was verified by actual observation. The progress of inductive knowledge is by the formation of successive hypotheses, and it frequently happens that the demolition of one or even many hypotheses is the direct road to a new and accurate hypothesis, i.e. to fresh knowledge. A hypothesis may, therefore, turn out to be entirely wrong, yet it may be of the greatest practical use.

The recognition of the importance of hypotheses has led to various attempts at drawing up exact rules for their formation, but logicians are generally agreed that only very elementary principles can be laid down. Thus a hypothesis must contain nothing which is at variance with known facts or principles: it should not postulate conditions which cannot be verified empirically. J. S. Mill (_Logic_ III. xiv. 4) laid down the principle that a hypothesis is not "genuinely scientific" if it is "destined always to remain a hypothesis": it must "be of such a nature as to be either proved or disproved by comparison with observed facts": in the same spirit Bacon said that in searching for causes in nature "Deum semper excipimus." Mill's principle, though sound in the abstract, has, except in a few cases, little practical value in determining the admissibility of hypotheses, and in practice any rule which tends to discourage hypothesis is in general undesirable. The most satisfactory check on hypothesis is expert knowledge in the particular field of research by which rigorous tests may be applied. This test is roughly of two kinds, first by the ultimate principles or presuppositions on which a particular branch of knowledge rests, and second by the comparison of correlative facts. Useful light is shed on this distinction by Lotze, who contrasts (_Logic_, § 273) _postulates_ ("absolutely necessary assumptions without which the content of the observation with which we are dealing would contradict the laws of our thought") with _hypotheses_, which he defines as conjectures, which seek "to fill up the postulate thus abstractly stated by specifying the concrete causes, forces or processes, out of which the given phenomenon really arose in this particular case, while in other cases maybe the same postulate is to be satisfied by utterly different though equivalent combinations of forces or active elements." Thus a hypothesis may be ruled out by principles or postulates without any reference to the concrete facts which belong to that division of the subject to explain which the hypothesis is formulated. A true hypothesis, therefore, seeks not merely to connect or colligate two separate facts, but to do this in the light of and subject to certain fundamental principles. Various attempts have been made to classify hypotheses and to distinguish "hypothesis" from a "theory" or a mere "conjecture": none of these have any great practical importance, the differences being only in degree, not in kind.

The adjective "hypothetical" is used, in the same sense, both loosely in contradistinction to "real" or "actual," and technically in the phrases "hypothetical judgment" and "hypothetical syllogism." (See LOGIC and SYLLOGISM.)

See Naville, _La Logique de l'hypothèse_ (1880), and textbooks of
logic, e.g. those of Jevons, Bosanquet, Joseph; Liebmann, _Der Klimax
d. Theorien_.

HYPOTRACHELIUM (Gr. [Greek: hypotrachêlion], the lower part of the neck, [Greek: trachêlos]), in classical architecture, the space between the annulet of the echinus and the upper bed of the shafts, including, according to C. R. Cockerell, the three grooves or sinkings found in some of the older examples, as in the temple of Neptune at Paestum and the temple of Aphaea at Aegina; there being only one groove in the Parthenon, the Theseum and later examples. In the temple of Ceres and the so-called Basilica at Paestum the hypotrachelium consists of a concave sinking carved with vertical lines suggestive of leaves, the tops of which project forward. A similar decoration is found in the capital of the columns flanking the tomb of Agamemnon at Mycenae, but here the hypotrachelium projects forward with a cavetto moulding, and is carved with triple leaves like the buds of a rose. In the Roman Doric Order the term was sometimes applied to that which is generally known as the "necking," the space between the fillet and the annulet.

HYPSOMETER (Gr. [Greek: hypsos], height, [Greek: metron], a measure), an instrument for measuring heights which employs the principles that the boiling-point of a liquid is lowered by diminishing the pressure, and that the barometric pressure varies with the height of the point of observation. The instrument consists of a cylindrical vessel in which the liquid, usually water, is boiled, surmounted by a jacketed column, in the outer partitions of which the vapour circulates, while in the central one a thermometer is placed. To deduce the height of the station from the observed boiling-point, it is necessary to know the relation existing between the boiling-point and pressure, and also between the pressure and height of the atmosphere.

HYRACOIDEA, a suborder of ungulate mammals represented at the present day only by the Syrian hyrax (_Procavia syriaca_), the "coney" of the Bible, and its numerous African relatives, all of which may be included in the single genus _Procavia_ (or _Hyrax_), and consequently in the family _Procaviidae_. These creatures have no proper English name, and are generally known as hyraxes, from the scientific term (_Hyrax_) by which they were for many years designated--a term which has unfortunately had to give place to the earlier _Procavia_. In size these animals may be compared roughly to rabbits and hares; and they have rodent-like habits, hunching up their backs after the fashion of some foreign members of the hare-family, more especially the Liu-Kiu rabbit. In the matter of nomenclature these animals have been singularly unfortunate. In the title "hyrax" they have, for instance, usurped the Greek name for the shrew-mouse; while in the Bible they have been given the old English name for the rabbit. Perhaps rock-rabbit would be the best name. At the Cape they are known to the Dutch as dass (badger), which has been anglicized into "dassie."

As regards the recent forms, the dentition in the fully adult animal
consists only of incisors and cheek-teeth, the formula being _i._ ½,
_c._ 0/0, _p._ 4/4 _m._ 3/3. There is, however, a minute upper canine
developed at first, which is early shed; and in extinct forms this
tooth was functional and molar-like. The upper incisors have
persistent pulps, and are curved longitudinally, forming a semicircle
as in rodents; they are, however, not flattened from before backwards
as in that order, but prismatic, with an antero-external, an
antero-internal and a posterior surface, the first two only being
covered with enamel; their tips are consequently not chisel-shaped,
but sharp-pointed. They are preceded by functional, rooted milk-teeth.
The lower incisors have long tapering roots, but not of persistent
growth; and are straight, directed somewhat forwards, with awl-shaped,
tri-lobed crowns. Behind the incisors is a considerable gap, followed
by the cheek-teeth, which are all contiguous, and formed almost
exactly on the pattern of some of the perissodactyle ungulates. The
milk-dentition includes three pairs of incisors and one of canines in
each jaw. The hyoid arch is unlike that of any known mammal. The
dorsal and lumbar vertebrae are very numerous, 28 to 30, of which 21
or 22 bear ribs. The tail is extremely short. There are no clavicles.
In the fore foot, the three middle toes are subequally developed, the
fifth is present, but smaller, and the first is rudimentary, although,
in one species at least, all its normal bones are present. The
terminal phalanges of the four outer digits are small, somewhat
conical and flattened in form. The carpus has a distinct os centrale.
There is a slight ridge on the femur in the place of a third
trochanter. The fibula is complete, thickest at its upper end, where
it generally unites with the tibia. The articulation between the tibia
and astragalus is more complex than in other mammals, the end of the
malleolus entering into it. The hind-foot is very like that of a
rhinoceros, having three well-developed toes. There is no trace of a
first toe, and the fifth meta-tarsal is represented by a small nodule.
The terminal phalange of the inner (or second) digit is deeply cleft,
and has a peculiar long curved claw, the others having short broad
nails. The stomach is formed upon much the same principle as that of
the horse or rhinoceros, but is more elongated transversely and
divided by a constriction into two cavities--a large left _cul de
sac_, lined by a very dense white epithelium, and a right pyloric
cavity, with a thick, soft, vascular lining. The intestinal canal is
long, and has, in addition to the ordinary short, but capacious and
sacculated caecum at the commencement of the colon, lower down, a pair
of large, conical, pointed caeca. The liver is much subdivided, and
there is no gall-bladder. The brain resembles that of typical
ungulates far more than that of rodents. The testes are permanently
abdominal. The ureters open into the fundus of the bladder as in some
Rodents. The female has six teats, of which four are inguinal and two
axillary, and the placenta is zonary and deciduous. There is a gland
on the back.

The more typical members of the genus are terrestrial in their habits,
and their cheek-teeth have nearly the same pattern as in rhinoceroses;
while the interval between the upper incisors is less than the width
of the teeth; and the lower incisors are only slightly notched at the
cutting edge. Vertebrae: C. 7, D. 22, L. 8, S. 6, C. 6. Of this form
the earliest known species, _P. capensis_, is the type; but there are
many other species, as _P. syriaca_, and _P. brucei_ from Syria and
eastern Africa. They inhabit mountainous and rocky regions, and live
on the ground. In a second section the molar teeth have the same
pattern as in _Palaeotherium_ (except that the third lower molar has
but two lobes); the interval between the upper incisors exceeds the
width of the teeth; and the lower incisors have distinctly tri-lobed
crowns. Vertebrae: C. 7, D. 21, L. 7, S. 5, C. 10. The members of this
section frequent the trunks and large branches of trees, sleeping in
holes. There are several species from Western and South Africa, as _P.
arboreus_ and _P. dorsalis_. The members of both groups appear to have
a power like that possessed by geckos of clinging to vertical surfaces
of rocks and trees by the soles of their feet.

_Extinct Hyracoids._--For many years extinct representatives of the
Hyracoidea were unknown, partly owing to the fact that certain fossils
were not recognized as really belonging to that group. The longest
known of these was originally named _Leptodon graecus_, but, on
account of the preoccupation of the generic title, the designation has
been changed to _Pliohyrax graecus_. This animal, whose remains occur
in the Lower Pliocene of both Attica and Samos, was about the size of
a donkey, and possessed three pairs of upper incisor teeth, of which
the innermost were large and trihedral, recalling those of the
existing genus. On the other hand, the two outer pairs of incisors
were in contact with one another and with the canines, so as to form
on each side a series continuous with the cheek-teeth.

The next representatives of the group occur in the Upper Eocene beds
of the Fayum district of Egypt, where the genera _Saghatherium_ and
_Megalohyrax_ occur. These are regarded as representing a distinct
family, the _Saghatheriidae_, characterized by the possession of the
full series of twenty-two teeth in the upper jaw, among which the
first pair of incisors was modified to form trihedral rootless tusks,
while the two remaining pairs were separated from one another and from
the teeth in front by gaps. The canine was like a premolar, and in
contact with the first tooth of that series; and the cheek-teeth were
short-crowned, with the premolar simpler than the molars, and a third
lobe to the last lower tooth of the latter series. The members of
this genus were small or medium-sized ungulates with single-rooted
incisors. On the other hand, the representatives of the contemporary
genus _Megalohyrax_ were approximately as large as _Pliohyrax_, and in
some instances had double roots to the second and third incisors.

It is now possible to define the suborder Hyracoidea as including
ungulates with a centrale in the carpus, plantigrade feet, in which
the first and fifth toes are reduced in greater or less degree, and
clavicles and a foramen in the lower end of the humerus are absent.
The femur has a small third trochanter, the radius and ulna and tibia
and fibula are respectively separate, at least in the young, and the
fibula articulates with the astragalus. The earlier forms had the full
series of 44 teeth, with the premolars simpler than the molars; but in
the later types the canines and some of the incisors disappear, and at
least the hinder premolars become molar-like. In all cases the first
upper incisors are large and rootless.

That the group originated in Africa there can be no reasonable doubt;
and it is remarkable that so early as the Upper Eocene the types in
existence differed comparatively little in structure from the modern
forms. In fact the hyraxes were then almost as distinct from other
mammals as they are at the present day.

See also C. W. Andrews, _Descriptive Catalogue of the Tertiary
Vertebrata of the Fayum_, British Museum (1906). (R. L.*)

HYRCANIA. (1) An ancient district of Asia, south of the Caspian Sea, and bounded on the E. by the river Oxus, called _Virkana_, or "Wolf's Land," in Old Persian. It was a wide and indefinite tract. Its chief city is called Tape by Strabo, Zadracarta by Arrian (probably the modern Astarabad). The latter is evidently the same as Carta, mentioned by Strabo as an important city. Little is known of the history of the country. Xenophon says it was subdued by the Assyrians; Curtius that 6000 Hyrcanians were in the army of Darius III. (2) Two towns named Hyrcania are mentioned, one in Hyrcania, the other in Lydia. The latter is said to have derived its name from a colony of Hyrcanians, transported thither by the Persians.

HYRCANUS ([Greek: Hykanos]), a Greek surname, of unknown origin, borne by several Jews of the Maccabaean period.

JOHN HYRCANUS I., high priest of the Jews from 135 to 105 B.C., was the youngest son of Simon Maccabaeus. In 137 B.C. he, along with his brother Judas, commanded the force which repelled the invasion of Judaea led by Cendebeus, the general of Antiochus VII. _Sidetes_. On the assassination of his father and two elder brothers by Ptolemy, governor of Jericho, his brother-in-law, in February 135, he succeeded to the high priesthood and the supreme authority in Judaea. While still engaged in the struggle with Ptolemy, he was attacked by Antiochus with a large army (134), and compelled to shut himself up in Jerusalem; after a severe siege peace was at last secured only on condition of a Jewish disarmament, and the payment of an indemnity and an annual tribute, for which hostages were taken. In 129 he accompanied Antiochus as a vassal prince on his ill-fated Parthian expedition; returning, however, to Judaea before winter, he escaped the final disaster. By the judicious mission of an embassy to Rome he now obtained confirmation of the alliance which his father had previously made with the growing western power; at the same time he availed himself of the weakened state of the Syrian monarchy under Demetrius II. to overrun Samaria, and also to invade Idumaea, which he completely subdued, compelling its inhabitants to receive circumcision and accept the Jewish faith. After a long period of rest he directed his arms against the town of Samaria, which, in spite of the intervention of Antiochus, his sons Antigonus and Aristobulus ultimately took, and by his orders razed to the ground (c. 100 B.C.). He died in 105, and was succeeded by Aristobulus, the eldest of his five sons. The external policy of Hyrcanus was marked by considerable energy and tact, and, aided as it was by favouring circumstances, was so successful as to leave the Jewish nation in a position of independence and of influence such as it had not known since the days of Solomon. During its later years his reign was much disturbed, however, by the contentions for ascendancy which arose between the Pharisees and Sadducees, the two rival sects or parties which then for the first time (under those names at least) came into prominence. Josephus has related the curious circumstances under which he ultimately transferred his personal support from the former to the latter.

JOHN HYRCANUS II., high priest from 78 to 40 B.C., was the eldest son of Alexander Jannaeus by his wife Alexandra, and was thus a grandson of the preceding. When his father died in 78, he was by his mother forthwith appointed high priest, and on her death in 69 he claimed the succession to the supreme civil authority also; but, after a brief and troubled reign of three months, he was compelled to abdicate both kingly and priestly dignities in favour of his more energetic and ambitious younger brother Aristobulus II. In 63 it suited the policy of Pompey that he should be restored to the high priesthood, with some semblance of supreme command, but of much of this semblance even he was soon again deprived by the arrangement of the pro-consul Gabinius, according to which Palestine was in 57 B.C. divided into five separate circles ([Greek: synodoi, synedria]). For services rendered to Caesar after the battle of Pharsalia, he was again rewarded with the sovereignty ([Greek: prostasia tou ethnous], Jos. _Ant._ xx. 10) in 47 B.C., Antipater of Idumaea, however, being at the same time made procurator of Judaea. In 41 B.C. he was practically superseded by Antony's appointment of Herod and Phasael to be tetrarchs of Judaea; and in the following year he was taken prisoner by the Parthians, deprived of his ears that he might be permanently disqualified for priestly office, and carried to Babylon. He was permitted in 33 B.C. to return to Jerusalem, where on a charge of treasonable correspondence with Malchus, king of Arabia, he was put to death in 30 B.C.

See Josephus (_Ant._ xiii. 8-10; xiv. 5-13; _Bell. Jud._ i. 2; i.
8-13). Also MACCABEES, _History_. (J. H. A. H.)

HYSSOP (_Hyssopus officinalis_), a garden herb belonging to the natural order _Labiatae_, formerly cultivated for use in domestic medicine. It is a small perennial plant about 2 ft. high, with slender, quadrangular, woody stems; narrowly elliptical, pointed, entire, dotted leaves, about 1 in. long and 1/3 in. wide, growing in pairs on the stem; and long terminal, erect, half-whorled, leafy spikes of small violet-blue flowers, which are in blossom from June to September. Varieties of the plant occur in gardens with red and white flowers, also one having variegated leaves. The leaves have a warm, aromatic, bitter taste, and are believed to owe their properties to a volatile oil which is present in the proportion of ¼ to ½%. Hyssop is a native of the south of Europe, its range extending eastward to central Asia. A strong tea made of the leaves, and sweetened with honey, was formerly used in pulmonary and catarrhal affections, and externally as an application to bruises and indolent swellings.

The hedge hyssop (_Gratiola officinalis_) belongs to the natural order _Scrophulariaceae_, and is a native of marshy lands in the south of Europe, whence it was introduced into Britain more than 300 years ago. Like _Hyssopus officinalis_, it has smooth opposite entire leaves, but the stems are cylindrical, the leaves twice the size, and the flowers solitary in the axils of the leaves and having a yellowish-red veined tube and bluish-white limb, while the capsules are oval and many-seeded. The herb has a bitter, nauseous taste, but is almost odourless. In small quantities it acts as a purgative, diuretic and emetic when taken internally. It was formerly official in the Edinburgh Pharmacopoeia, being esteemed as a remedy for dropsy. It is said to have formed the basis of a celebrated nostrum for gout, called _Eau médicinale_, and in former times was called _Gratia Dei_. When growing in abundance, as it does in some damp pastures in Switzerland, it becomes dangerous to cattle. G. _peruviana_ is known to possess similar properties.

The hyssop (_'ezob_) of Scripture (Ex. xii. 22; Lev. xiv. 4, 6; Numb.
xix. 6, 18; 1 Kings v. 13 (iv. 33); Ps. li. 9 (7); John xix. 29), a
wall-growing plant adapted for sprinkling purposes, has long been the
subject of learned disputation, the only point on which all have
agreed being that it is not to be identified with the _Hyssopus
officinalis_, which is not a native of Palestine. No fewer than
eighteen plants have been supposed by various authors to answer the
conditions, and Celsius has devoted more than forty pages to the
discussion of their several claims. By Tristram (_Oxford Bible for
Teachers_, 1880) and others the caper plant (_Capparis spinosa_) is
supposed to be meant; but, apart from other difficulties, this
identification is open to the objection that the caper seems to be, at
least in one passage (Eccl. xii. 5), otherwise designated
(_'abiy-yônah_). Thenius (on 1 Kings v. 13) suggests _Orthotrichum
saxatile_. The most probable opinion would seem to be that found in
Maimonides and many later writers, according to which the Hebrew
_'ezob_ is to be identified with the Arabic _sa'atar_, now understood
to be _Satureja Thymus_, a plant of very frequent occurrence in Syria
and Palestine, with which _Thymus Serpyllum_, or wild thyme, and
_Satureja Thymbra_ are closely allied. Its smell, taste and medicinal
properties are similar to those of _H. officinalis_. In Morocco the
_sa'atar_ of the Arabs is _Origanum compactum_; and it appears
probable that several plants of the genera _Thymus_, _Origanum_ and
others nearly allied in form and habit, and found in similar
localities, were used under the name of hyssop.

HYSTASPES (the Greek form of the Persian _Vishtaspa_). (1) A semi-legendary king (_kava_), praised by Zoroaster as his protector and a true believer, son of Aurvataspa (Lohrasp). The later tradition and the Shahname of Firdousi makes him (in the modern form Kai Gushtasp) king of Iran. As Zoroaster probably preached his religion in eastern Iran, Vishtaspa must have been a dynast in Bactria or Sogdiana. The Zoroastrian religion was already dominant in Media in the time of the Assyrian king Sargon (c. 715 B.C.), and had been propagated here probably in much earlier times (cf. PERSIA); the time of Zoroaster and Vishtaspa may therefore be put at c. 1000 B.C. (2) A Persian, father of Darius I., under whose reign he was governor of Parthia, as Darius himself mentions in the Behistun inscription (2. 65). By Ammianus Marcellinus, xxiii. 6. 32, and by many modern authors he has been identified with the protector of Zoroaster, which is equally impossible for chronological and historical reasons, and from the evidence of the development of Zoroastrianism itself (see PERSIA: _Ancient History_). (Ed. M.)

HYSTERESIS (Gr. [Greek: hysterêsis], from [Greek: hysterein], to lag behind), a term added to the vocabulary of physical science by J. A. Ewing, who defines it as follows: When there are two qualities M and N such that cyclic variations of N cause cyclic variations of M, then if the changes of M lag behind those of N, we may say that there is hysteresis in the relation of M to N (_Phil. Trans._, 1885, 176, p. 524). The phenomenon is best known in connexion with magnetism. If an iron bar is subjected to a magnetic force which is first gradually increased to a maximum and then gradually diminished, the resulting magnetization of the bar for any given value of the magnetic force will be greater when the force is decreasing than when it is increasing; the iron always tends to retain the magnetic condition which it has previously acquired, and changes of its magnetization consequently lag behind changes of the magnetic force. Thus there is hysteresis in the relation of magnetization to magnetic force. In consequence of hysteresis the process of magnetizing a piece of iron to a certain intensity and then restoring it to its original condition, or of effecting a double reversal of its magnetization, involves the expenditure of energy, which is dissipated as heat in the iron. Electrical generators and transformers often contain pieces of iron the magnetization of which is reversed many times in a second, and in order to economize power and to avoid undue heating it is essential that hysteresis should in such cases be as small as possible. Iron and mild steels showing remarkably little hysteresis are now specially manufactured for use in the construction of electrical machinery. (See MAGNETISM.)

HYSTERIA, a term applied to an affection which may manifest itself by a variety of symptoms, and which depends upon a disordered condition of the highest nervous centres. It is characterized by psychical peculiarities, while in addition there is often derangement of the functions subserved by the lower cerebral and spinal centres. Histological examination of the nervous system has failed to disclose associated structural alterations.

By the ancients and by modern physicians down to the time of Sydenham the symptoms of hysteria were supposed to be directly due to disturbances of the uterus (Gr. [Greek: hystera], whence the name). This view is now universally recognized to be erroneous. The term "functional" is often used by English neurologists as synonymous with hysterical, a nomenclature which is tentatively advantageous since it is at least non-committal. P. J. Möbius has defined hysteria as "a state in which ideas control the body and produce morbid changes in its functions." P. Janet, who has done much to popularize the psychical origin of the affection, holds that there is "a limitation of the field of consciousness" comparable to the contraction of the visual fields met with in the disease. The hysterical subject, according to this view, is incapable of taking into the field of consciousness all the impressions of which the normal individual is conscious. Strong momentary impressions are no longer controlled so efficiently because of the defective simultaneous impressions of previous memories. Hence the readiness with which the impulse of the moment is obeyed, the loss of emotional control and the increased susceptibility to external suggestion, which are so characteristic. A secondary subconscious mental state is engendered by the relegation of less prominent impressions to a lower sphere. The dual personality which is typically exemplified in somnambulism and in the hypnotic state is thus induced. The explanation of hysterical symptoms which are independent of the will, and of the existence of which the individual may be unaware, is to be found in a relative preponderance of this secondary subconscious state as compared with the primary conscious personality. An elaboration of this theory affords an explanation of hysterical symptoms dependent upon a "fixed idea." The following definition of hysteria has recently been advanced by J. F. F. Babinski: "Hysteria is a psychical condition manifesting itself principally by signs that may be termed primary, and in an accessory sense others that we may call secondary. The characteristic of the primary signs is that they may be exactly reproduced in certain subjects by suggestion and dispelled by persuasion. The characteristic of the secondary signs is that they are closely related to the primary phenomena."

The causes of hysteria may be divided into (a) the predisposing, such as hereditary predisposition to nervous disease, sex, age and national idiosyncrasy; and (b) the immediate, such as mental and physical exhaustion, fright and other emotional influences, pregnancy, the puerperal condition, diseases of the uterus and its appendages, and the depressing influence of injury or general disease. Perhaps, taken over all, hereditary predisposition to nerve-instability may be asserted as the most prolific cause. There is frequently direct inheritance, and cases of epilepsy and insanity or other form of nervous disease are rarely wanting when the family history is carefully enquired into. As regards age, the condition is apt to appear at the evolution periods of life--puberty, pregnancy and the climacteric--without any further assignable cause except that first spoken of. It is rare in young children, but very frequent in girls between the ages of fifteen and twenty-five, while it sometimes manifests itself in women at the menopause. It is much more common in the female than in the male--in the proportion of 20 to 1. Certain races are more liable to the disease than others; thus the Latin races are much more prone to hysteria than are those who come of a Teutonic stock, and in more aggravated and complex forms. In England it has been asserted that an undue proportion of cases occur among Jews. Occupation, or be it rather said want of occupation, is a prolific cause. This is noticeable more especially in the higher classes of society.

An hysterical attack may occur as an immediate sequel to an epileptic fit. If the patient suffers only from _petit mal_ (see EPILEPSY), unaccompanied by true epileptic fits, the significance of the hysterical seizure, which is really a post-epileptic phenomenon, may remain unrecognized.

It is convenient to group the very varied symptoms of hysteria into paroxysmal and chronic. The popular term "hysterics" is applied to an explosion of emotionalism, generally the result of mental excitement, on which convulsive fits may supervene. The characters of these vary, and may closely resemble epilepsy. The hysterical fit is generally preceded by an aura or warning. This sometimes takes the form of a sensation as of a lump in the throat (_globus hystericus_). The patient may fall, but very rarely is injured in so doing. The eyes are often tightly closed, the body and limbs become rigid, and the back may become so arched that the patient rests on her heels and head (_opisthotonos_). This stage is usually followed by violent struggling movements. There is no loss of consciousness. The attack may last for half-an-hour or even longer. Hysterical fits in their fully-developed form are rarely seen in England, though common in France. In the chronic condition we find an extraordinary complexity of symptoms, both physical and mental. The physical symptoms are extremely diverse. There may be a paralysis of one or more limbs associated with rigidity, which may persist for weeks, months or years. In some cases, the patient is unable to walk; in others there are peculiarities of the gait quite unlike anything met with in organic disease. Perversions of sensation are usually present; a common instance is the sensation of a nail being driven through the vertex of the head (_clavus hystericus_). The region of the spine is a very frequent seat of hysterical pain. Loss of sensation (_anaesthesia_), of which the patient may be unaware, is of common occurrence. Very often this sensory loss is limited exactly to one-half of the body, including the leg, arm and face on that side (_hemianaesthesia_). Sensation to touch, pain, heat and cold, and electrical stimuli may have completely disappeared in the anaesthetic region. In other cases, the anaesthesia is relative or it may be partial, certain forms of sensation remaining intact. Anaesthesia is almost always accompanied by an inability to recognize the exact position of the affected limb when the eyes are closed. When hemianaesthesia is present, sight, hearing, taste and smell are usually impaired on that side of the body. Often there is loss of voice (hysterical aphonia). It is to such cases of hysterical paralysis and sensory disturbance that the wonderful cures effected by quacks and charlatans may be referred. The mental symptoms have not the same tendency to pass away suddenly. They may be spoken of as inter-paroxysmal and paroxysmal. The chief characteristics of the former are extreme emotionalism combined with obstructiveness, a desire to be an object of interest and a constant craving for sympathy which is often procured at an immense sacrifice of personal comfort. Obstructiveness is the invariable symptom. Hysteria may pass into absolute insanity.

The treatment of hysteria demands great tact and firmness on the part of the physician. The affection is a definite entity and has to be clearly distinguished from malingering, with which it is so often erroneously regarded as synonymous. Drugs are of little value. The moral treatment is all-important. In severe cases, removal from home surroundings and isolation, either in a hospital ward or nursing home, are essential, in order that full benefit may be derived from psychotherapeutic measures.

BIBLIOGRAPHY.--Charcot, _Leçons sur les maladies du système nerveuse_
(1877); S. Weir Mitchell, _Lectures on Diseases of the Nervous System
especially in Women_ (1885); Buzzard, _Simulation of Hysteria by
Organic Nervous Disease_ (1891); Pitres, _Leçons cliniques sur
l'hystérie et l'hypnotisme_ (1891); Richer, _Études cliniques sur la
grande hystérie_ (1891); Gilles de la Tourette, _Traité clinique et
thérapeutique de l'hystérie_ (1891); Bastian, _Hysterical or
Functional Paralysis_ (1893); Ormerod, Art. "Hysteria," in Clifford
Allbutt's _System of Medicine_ (1899); Camus and Pagnez, _Isolement et
Psychotherapie_ (1904). (J. B. T.; E. Bra.)

HYSTERON-PROTERON (Gr. [Greek: hysteron], latter, and [Greek: proteron], former), a figure of speech, in which the order of words or phrases is inverted, and that which should logically or naturally come last is put first, to secure emphasis for the principal idea; the classical example is Virgil's "_moriamur et in media arma ruamus,_" "let us die and charge into the thick of the fight" (Aen. ii. 358). The term is also applied to any inversion in order of events, arguments, &c.

HYTHE, a market town and watering-place, one of the Cinque Ports, and a municipal and parliamentary borough of Kent, England, 67 m. S.E. by E. of London on a branch of the South Eastern & Chatham railway. Pop. (1901) 5557. It is beautifully situated at the foot of a steep hill near the eastern extremity of Romney Marsh, about half a mile from the sea, and consists principally of one long street running parallel with the shore, with which it is connected by a straight avenue of wych elms. On account of its fine situation and picturesque and interesting neighbourhood, it is a favourite watering-place. A sea-wall and parade extend eastward to Sandgate, a distance of 3 m. There is communication with Sandgate by means of a tramway along the front. On the slope of the hill above the town stands the fine church of St Leonard, partly Late Norman, with a very beautiful Early English chancel. The tower was rebuilt about 1750. In a vault under the chancel there is a collection of human skulls and bones supposed to be the remains of men killed in a battle near Hythe in 456. Lionel Lukin (1742-1834), inventor of the life-boat, is buried in the churchyard. Hythe possesses a guildhall founded in 1794 and two hospitals, that of St Bartholomew founded by Haimo, bishop of Rochester, in 1336, and that of St John (rebuilt in 1802), of still greater antiquity but unknown date, founded originally for the reception of lepers. A government school of musketry, in which instructors for the army are trained, was established in 1854, and has been extended since, and the Shorncliffe military camp is within 2½ m. of the town.

Lympne, which is now 3 m. inland, is thought to have been the original harbour which gave Hythe a place among the Cinque Ports. The course of the ancient estuary may be distinctly traced from here along the road to Hythe, the sea-sand lying on the surface and colouring the soil. Here are remains of a Roman fortress, and excavations have brought to light many remains of the Roman _Portus Lemanis_. Large portions of the fortress walls are standing. At the south-west corner is one of the circular towers which occurred along the line of wall. The site is now occupied by the fine old castellated mansion of Studfall castle, formerly a residence of the archdeacons of Canterbury. The name denotes a fallen place, and is not infrequently thus applied to ancient remains. The church at Lympne is Early English, with a Norman tower built by Archbishop Lanfranc, and Roman material may be traced in the walls. A short distance east is Shipway or Shepway Cross, where some of the great assemblies relating to the Cinque Ports were held. A mile north from Hythe is Saltwood Castle, of very ancient origin, but rebuilt in the time of Richard II. The castle was granted to the see of Canterbury in 1026, but escheated to the crown in the time of Henry II., when the murder of Thomas à Beckett is said to have been concerted here, and having been restored to the archbishops by King John remained a residence of theirs until the time of Henry VIII. It was restored as a residence in 1882. About 2 m. N.W. of Saltwood are remains of the fortified 14th-century manor-house of Westenhanger. It is quadrangular and surrounded by a moat, and of the nine towers (alternately square and round) by which the walls were defended, three remain.

The parliamentary borough of Hythe, which includes Folkestone, Sandgate and a number of neighbouring villages, returns one member. The town is governed by a mayor, 4 aldermen and 12 councillors. Area 2617 acres.

Hythe (Heda, Heya, Hethe, Hithe, _i.e._ landing-place) was known as a port in Saxon times, and was granted by Halfden, a Saxon thegn, to Christ Church, Canterbury. In the Domesday Survey the borough is entered among the archbishop's lands as appurtenant to his manor of Saltwood, and the bailiff of the town was appointed by the archbishop. Hythe was evidently a Cinque Port before the Conquest, as King John in 1205 confirmed the liberties, viz. freedom from toll, the right to be impleaded only at the Shepway court, &c., which the townsmen had under Edward the Confessor. The liberties of the Cinque Ports were confirmed in Magna Carta and later by Edward I. in a general charter, which was confirmed, often with additions, by subsequent kings down to James II. John's charter to Hythe was confirmed by Henry IV., Henry V. and Henry VI. These charters were granted to the Cinque Ports in return for the fifty-seven ships which they supplied for the royal service, of which five were contributed by Hythe. The ports were first represented in the parliament of 1365, to which they each sent four members.

Hythe was governed by twelve jurats until 1574, when it was incorporated by Elizabeth under the title of the mayor, jurats and commonalty of Hythe; a fair for the sale of fish, &c., was also granted, to be held on the feast of St Peter and St Paul. As the sea gradually retreated from Hythe and the harbour became choked up with sand, the town suffered the fate of other places near it, and lost its old importance.

I the ninth letter of the English and Latin alphabet, the tenth in the Greek and Phoenician, because in these the symbol Teth (the Greek [theta]) preceded it. Teth was not included in the Latin alphabet because that language had no sound corresponding to the Greek [theta], but the symbol was metamorphosed and utilized as the numeral C = 100, which took this form through the influence of the initial letter of the Latin _centum_. The name of I in the Phoenician alphabet was _Yod_. Though in form it seems the simplest of letters it was originally much more complex. In Phoenician it takes the form [symbol], which is found also in the earliest Syriac and Palestinian inscriptions with little modification. Ultimately in Hebrew it became reduced to a very small symbol, whence comes its use as a term of contempt for things of no importance as in "not one _jot_ or tittle" (Matthew v. 18). The name passed from Phoenician to Greek, and thence to the Latin of the vulgate as _iota_, and from the Latin the English word is derived. Amongst the Greeks of Asia it appears only as the simple upright I, but in some of the oldest alphabets elsewhere, as Crete, Thera, Attica, Achaia and its colonies in lower Italy, it takes the form [symbol] or S, while at Corinth and Corcyra it appears first in a form closely resembling the later Greek _sigma_ [Sigma]. It had originally no cross-stroke at top and bottom. I being not _i_ but _z_. The Phoenician alphabet having no vowel symbols, the value of _yod_ was that of the English _y_. In Greek, where the consonant sound had disappeared or been converted into _h_, I is regularly used as a vowel. Occasionally, as in Pamphylian, it is used dialectically as a glide between _i_ and another vowel, as in the proper name [Greek: Damatriius]. In Latin I was used alike for both vowel and consonant, as in _iugum_ (yoke). The sound represented by it was approximately that still assigned to _i_ on the continent. Neither Greek nor Latin made any distinction in writing between short and long _i_, though in the Latin of the Empire the long sound was occasionally represented by a longer form of the symbol I. The dot over the _i_ begins in the 5th or 6th century A.D. In pronunciation the English short _i_ is a more open sound than that of most languages, and does not correspond to the Greek and Latin sound. Nor are the English short and long _i_ of the same quality. The short _i_ in Sweet's terminology is a high-front-wide vowel, the long _i_, in English often spelt _ee_ in words like _seed_, is diphthonged, beginning like the short vowel but becoming higher as it proceeds. The Latin short _i_, however, in final syllables was open and ultimately became _e_, e.g. in the neuter of _i_-stems as _utile_ from _utili-s_. Medially both the short and the long sounds are very common in syllables which were originally unaccented, because in such positions many other sounds passed into _i_: _officio_ but _facio_, _redimo_ but _emo_, _quidlibet_ but _lubet_ (_libet_ is later); _collido_ but _laedo_, _fido_ from an older _feido_, _istis_ (dative plural) from an earlier _istois_. (P. Gi.)

IAMBIC, the term employed in prosody to denote a succession of verses, each consisting of a foot or metre called an iambus ([Greek: iambos]), formed of two syllables, of which the first is short and the second long (u --). After the dactylic hexameter, the iambic trimeter was the most popular metre of ancient Greece. Archilochus is said to have been the inventor of this iambic verse, the [Greek: trimetros] consisting of three iambic fed. In the Greek tragedians an iambic line is formed of six feet arranged in obedience to the following scheme:--

u -- | u -- | u -- | u -- | u -- | u -- |
u u u | u u u | u u u | u u u | u u u | |
-- -- | | -- -- | | -- -- | |
-- u u | | -- u u | | | |
u u -- | | | | | |

Much of the beauty of the verse depends on the caesura, which is usually In the middle of the third foot, and far less frequently in the middle of the fourth. The English language runs more naturally in the iambic metre than in any other. The normal blank verse in English is founded upon an iambic basis, and Milton's line--

And swims | or sinks | or wades | or creeps | or flies | --