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or disappearance of one phase of shell-formation before a later one area becomes strongly emarginated and can be traced through the is entered upon.
more mature embryos to the cephalic lobes or labial processes of the The development of the aquatic Pulmonata from the egg offers adult Limnaeus (fig. 61). considerable facilities for study, and that of Limnaeus has been The increase of the visceral dome, its spiral twisting, and the elucidated by E. R. Lankester, whilst H. Rabl has with remarkable gradual closure of the space overhung by the mantle-skirt so as to skill applied the method of sections to the study of the minute starijo od embryos of Planorbis. The chief features in the development of Wales Limnaeus are exhibited in fig. 60. There is not a very large amount
El of food-material present in the egg of this snail, and accordingly the
Ad 2920 cells resulting from division are not so unequal as in many other cases. The four cells first formed are of equal size, and then fournisseur de
ogniti smaller cells
are formed by division of these four so as to lie at one end of the first four (the pole corresponding to that at which the directive corpuscles "are extruded and remain). The smaller cells
o-due now divide and spread over the four larger cells; at the same time
SON a space-the cleavage cavity or blastocoel-forms in the centre of the mulberry-like mass. Then the large cells recommence the
f 1467 process of division and sink into the hollow of the sphere, leaving an elongated groove, the blastopore, on the surface. The invaginated
w cells (derived from the division of the four big cells) form the endo
Kas T derm or arch-enteron; the outer cells are the ectoderm. The blasto
VS DA pore now closes along the middle part of its course, which coincides
மாயyal him to be
Fig. 61.-A, B, C. Three views of Limnaeus stagnalis, in order to
Soovim show the persistence of the larval velar area y, as the circum-oral lobes -2005 one
of the adult. m, Mouth: f, foot; v, velar area, the margin v corre
sponding with the ciliated band which demarcates the velar arca 20
or velum of the embryo Gastropod (see fig. 4, D, E, F, H, I, u).
convert it into a lung-sac with a small contractile aperture, belong to stages in the development later than any represented in our figures.
We may now revert briefly to the internal organization at a period when the trochosphere is beginning to show a prominent foot growing out from the area where the mid-region of the elongated blastopore
was situated, and having therefore at one end of it the mouth and agore
at the other the anus. Fig. 60 represents such an embryo under slight compression as seen by transmitted light. The ciliated band
of the left side of the velar area is indicated by a line extending TW Szig
from v to v; the foot f is seen between the pharynx ph and the pedicle of invagination pi. The mass of the arch-enteron or invaginated endodermal sac has taken on a bilobed form, and its cells
are swollen (gs and tge). This bilobed sac becomes entirely the liver X
in the adult; the intestine and stomach are formed from the pedicle
of invagination, whilst the pharynx, oesophagus and crop form from Кр
the stomodaeal invagination ph. To the right in the figure) of the ss
rectal peduncle is seen the deeply invaginated shell-gland ss, with a FIG. 60.-Embryo of Linnaeus stagnalis, at a stage when the secretion sk protruding from it. The shell-gland is destined in Trochosphere is developing foot and shell-gland and becoming a
Limnaeus to become very rapidly stretched out, and to disappear. Veliger, seen as a transparent object under slight pressure. (Lan- Farther up, within the velar area, the rudiments of the cerebrai kester.)
nerve-ganglion ng are seen separating from the ectoderm. A remarkph, Pharynx (stomodacal in. -20 attachment to the ecto
able cord of cells having a position just below the integument occurs vagination).
derm is coincident with the
on each side of the head. In the figure the cord of the left side is 7, 9, The ciliated band marking hindmost extremity of the
marked re. This paired organ consists of a string of cells which for out the velum.
elongated blastopore of fig. are perforated by a duct opening to the exterior and ending internally ng, Cerebral nerve-ganglion.
in a flame-cell. Such cannulated cells are characteristic of the nephre, Stiebel's canal" (left side), Ige, Mesoblastic (skeletotrophic ridia of many worms, and the organs thus formed in the embryo probably, an
and muscular) cells
invest-Limnaeus are embryonic nephridia. The most important fact about embryonic nephridium. ing gs, the bilobed arch them is that they disappear, and are in no way connected with
the sh, The primitive shell-sac. or enteron or lateral vesicles typical nephridium of the adult. In reference to their first observer shell-gland.
of invaginated endoderm, they were formerly called "Stiebel's canals." Other Pulmonata pi, The rectal peduncle or which will develop into liver possess, when embryos, Stiebel's canals in a more fully developed pedicle of invagination; its f, The foot.
state, for instance, the common slug Limax. Here too they disin position with the future " foot." One end of the blastopore other Gastropoda. In the marine Streptoneura they are ectodermic
appear during embryonic life. Similar larval nephridia occur in around it to form the stomodaeum or fore-gut and mouth. The projections which ultimately fall off; in the Opisthobranchs they other extreme end closes, but the invaginated endoderm cells remain
are closed pouches; in Paludina and Bithynia they are canals as in
Pulmonata. in continuity with this extremity of the blastopore, and form the
Marine Pulmonala.-Whilst the Pulmonata are essentially a although the endoderm cells retain no contact with the middle region terrestrial and fresh-water group, there is one genus
of slug-like of the now closed-up blastopore. The anal opening forms at a late period by a very short ingrowth or proctodaeum coinciding with the blind termination of the rectal peduncle (fig. 60, pi). Турира
The body-cavity and the muscular, fibrous and vascular tissues are traced partly to two symmetrically disposed "mesoblasts," alo which bud off from the invaginated arch-enteron, partly to cells derived from the ectoderm, which at a very early stage is connected by long processes with the invaginated endoderm. The external form of the embryo goes through the same changes as in other Gastropods, and is not, as was held previously to Lankester's obser
FIG. 62.-Oncidium longanum, a littoral Pulmonate, found on the vations, exceptional. When the middle and hinder regions of the
shores of the Indian and Pacific Oceans (Mauritius, Japan). blastopore are closing in, an equatorial ridge of ciliated cells is formed, converting the embryo into a typical trochosphere. Pulmonates which frequent the sea-coast (Oncidium, fig. 62). Karl
The foot now protrudes below the mouth, and the post-oral hemi- Semper has shown that these slugs have, in addition to the usual sphere of the trochosphere grows more rapidly then the anterior or pair of cephalic eyes, a number of eyes developed upon the dorsal velar area. The young foot shows a bilobed form. Within the velar integument. These dorsal eyes are very perfect in elaboration, area the eyes and the cephalic tentacles commence to rise up, and possessing lens, retinal nerve-end cells, retinal pigment and optic on the surface of the
post-oral region is formed a cap-like shell and nerve. Curiously enough, however, they differ from the cephalic an encircling ridge, which gradually increases in prominence and Molluscan eye in the fact that, as in the vertebrate eye, the filaments becomes the freely depending mantle-skirt. The outline of the velar of the optic nerve penetrate the retina, and are connected with the
20ம் aital 1 Szouga D
surfaces of the nerve-end cells nearer the lens instead of with the organs. Endodonta. Punctum. Sphyradium. Laoma. Pyreopposite end. The significance of this arrangement is not known, midula. but it is important to note, as shown by V. Henson, S. J. Hickson and Fam. 9.-Orthalicidae. Shell external, ovoid, the last whor! others, that in the bivalves Pecten and Spondylus, which also have swollen, aperture oval with a simple border; radular teeth in eyes upon the mantle quite distinct from typical cephalic eyes, oblique rows. Orthalicus. there is the same relationship as in Oncidiidae of the optic nerve to Fam. io.-Bulimulidae. Jaw formed of folds imbricated exter. the retinal cells. In both Oncidiidae and Pecten the pallial eyes have nally and meeting at an acute angle near the base. Bulimulus. probably been developed by the modification of tentacles, such as Peliella. Amphibulimus. coexist in an unmodified form with the eyes. The Oncidiidae are, Fam. 11.-Cylindrellidae. Shell turriculated, with numerous according to K. Semper, pursued as food by the leaping fish Perioph. whorls, the last more or less detached. Cylindrella. thalmus, and the dorsal eyes are of especial value to them in aiding Fam. 12.-Pupidae. Shell external, with clongated spire and them to escape from this enemy.
numerous whorls, aperture generally narrow; male genital Sub-order 1.-BASOMMATOPHORA. Pulmonata with an external duct without multifid vesicles. Pupa, British. Eucalodium. shell. The head bears a single pair of contractile but not invaginable Verligo, British. Buliminus, British. Clausilia, British. Balea. tentacles, at the base of which are the cyes. Penis at some distance Zospeum. Megaspira. Strophia. Anosloma. from the female aperture, except in Amphibola and Siphonaria. Fam. 13.-Stenogyridae. Shell elongated, with a more or less All have an osphradium, except the Auriculidoe, which are terres. obtuse summit; aperture with a simple border. Achalina. trial, and it is situated outside the pallial cavity in those forms in Stenogyra. Ferussacia, British. Cionella. Caccilianella. which water is not admitted into the lung. There is a veliger stage Azeca. O peas. in development, but the velum is reduced.
Fam. 14.--Helicteridae. Shell bulimoid, dextral or sinistral; Fam. i.-Auriculidae. Terrestrial and usually littoral; genital radular teeth, expanded at their extremities and multicuspidate.
duct monaulic, the penis being connected with the aperture by Helicler. Tornalellina. an open or closed groove; shell with a prominent spire, the Tribe 2.-AGNATHA. No jaws; teeth narrow and pointed; internal partitions often absorbed and the aperture denticulated. carnivorous. Auricula. Cassidula. Alexia. Melampus. Carychium, Fam. 1.-Oleacinidae. Shell oval, elongated, with narrow aperterrestrial, British. Scarabus. Leuconia, British. Blauneria. ture; neck very long; labial palps prominent. Olcacing Pedipes.
(Glandina). Streplosiyla. Fam. 2.-Olinidac. Shell with short spire, and wide oval aperture; Fam. 2.-Testacellidae. Shell globular or auriform, external or tentacles short. Otina, British. Camplonyx, terrestrial.
partly covered by the mantle. Streplaxis. Gibbulina. Aerope. Fam. 3. - Amphibolidae. Shell spirally coiled; head broad, Rhylida. Daudebardia. Testacella. Chlamydophorus. Schizo
without prominent tentacles; foot short, operculated; marine. glossa. Amphibola.
Fam. 3.- Rathouisiidae. No shell, a carinated mantle covering Fam. 4. -Siphonariidae. Visceral mass and shell conical; ten- the whole body; male and female apertures distant, the female
tacles atrophied; head expanded; genital apertures con- near the anus. Ralhouisia. Atopos. tiguous; marine animals, with an aquatic pallial cavity con- Tribe 3.-ELASMOGNATHA. Jaw with a well-developed dorsal taining secondary branchial laminae. Siphonaria.
appendage. Fam. 5.-Gadiniidae. Visceral mass and shell conical; head Fam. i.-Succincidae. Anterior tentacles much reduced; male
flattened; pallial cavity aquatic, but without a branchia; and female apertures contiguous but distinct; shell thin, genital apertures separated. Godinio.
spiral, with short spire. Succinca, British. Homalonyx. HyaFam. 6.–Chilinidac. "Shell ovoid, with short spire, wide aperture limax. Neohyalimax.
and folded columella; inserior pallial lobe thick; visceral Fam. 2.- Jancllidae. Limaciform, with internal rounded shell; commissure still twisted. Chilina.
mantle very small and triangular; pulmonary chamber with Fam. 7.-Limnacidae. Shell thin, dextral, with prominent spire tracheae; no anterior tentacles. Janella. Aneilella. Aneilea. and oval aperture; no inferior pallial lobe. Limnaca, British. Triboniophorus. Amphipeplea, British.
Tribe 4.-DITREMATA. Male and female apertures distant. Fam. 8.-Pompholygidae. Shell dextral, hyperstrophic, animal Fam. 1.- Vaginulidae. No shell; limacisorm; terrestrial; sinistral. Pompholyx. Choanomphalus.
female aperture on right side in middle of body; anus erior. Fam. 9.-Planorbidae. Visceral mass and shell sinistral; inferior Vaginula.
pallial lobe very prominent, and transformed into a branchia. Fam. 2.-Oncidiidae. No shell; limaciform; littoral; female Planorbis, BritishBulinus. Miratesta.
aperture posterior, near anus; a reduced pulmonary
cavity Fam. 10.--Ancylidae. Shell conical, not spiral; inferior pallial with a distinct aperture. Oncidium. Oncidiella, British.
lobe transformed into a branchia. Ancylus, British. Lolia. Peronia. Grundlachia.
AUTHORITIES.-L. Boutan, "La Cause principale de l'asymétrie Fam. 11. -- Physidae. Visceral mass and shell sinistrally coiled: des mollusques gastéropodes.", Arch. de zool. expér. (3), vii. (1899); shell thin, with narrow aperture; no inferior pallial lobe. Physa, A. Lang, Versuch einer Erklärung der Asymmetric der Gastro
British. A plexa, British.
poder," Vierteljahrsschr, naturforsch. Gesellschaft: Zürich, 36 (1892): of tentacles, except Janellidae and Vertigo; these tentacles are in. vaginable, and the eyes are borne on the summits of the posterior poda," Zool. “ Challenger
de zool. expér. (3), x: (1903);
P. Pelseneer, ".Report on the Ptero
Expedit. pts. Iviii., 'Ixv., lxvi. (1887, pair. Male and female genital apertures open into a common yestibule, except in Vaginulidae and Oncidiidae. Except in Oncidium, fères," Arch. de biol. xiv. (1895); W. A. Herdman, “On the Structure
P. Pelseneer, “Protobranches aériens et Pulmonés branchi
1888); there is no longer a veliger stage in development. Tribe 1.-HOLOGNATHA. Jaw simple, without a superior apo branchiate Mollusca," Quarl. Journ. Mic. Sci. (1892): J. T. Cunning:
and Functions of the Cerata or Dorsal Papillae in some Nudi. pendage.
ham, "On the Structure and Relations of the Kidney in Aplysia, Fam. 1.-Selenitidae. Radula with elongated and pointed teeth, Mill. Zool. Stat. Neapel, iv. (1883): Böhmig,“ Zur feineren Anatomie like those of the Agnatha; a jaw present. Pluionia. Trigo- von Rhodope veranyi, Kölliker," Zeitschr. S. Wiss. Zool. vol. Ivi. (1893). nochlamys.
TREATISES.-S. P. Woodward, Manual of the Mollusca (2nd ed., Fam. 2.--Zonitidae. Shell external, smooth, heliciform
with appendix, London, 1869); E. Forbes and S. Hanley, History Aattened; radula with pointed marginal teeth. Zoniles, of British Mollusca (4 vols., London, 1853); Alder and Hancock,
British. Ariophanla. Orpiclla. Vitrina. Helicarion.
Monograph of British Nudibranchiaie Mollusca (London, Roy: cella. Urocyclus. Parmarion. Amalia.
Agriolimax. by E. Ray Lankester, pt. v. (1906); E. Ray Lankester, “ Mollusca," Mesolimax. Monochroma. Paralimax. Metalimax. Fam. 4.--Philomycidae. No shell; mantle covers the whole debted.
in 9th ed. of this Encyclopaedia, to which this article is much in.
( T. C.) surlace of the body; radula with squarish teeth. Philomycus. Fam. 5.--Ostracolethidae. Shell largely chitinous, not spiral, its
GASTROTRICHA, a' small group of fairly uniform animals calcareous apex projecting through a small hole in the mantle. Ostracolelhe.
which live among Rotifers and Protozoa at the bottom of ponds Fam. 6.- Arionidae. Shell internal, or absent; mantle restricted and marshes, biding amongst the recesses of the algae and
to the anterior and middle part of the body; radula with sphagnum and other fresh-water plants and eating organic squarish teeth. Arion, British. Geomalacus. Ariolimox. Ana- débris and Infusoria. They are of minute size varying from one
denus. Fam. 7. - Helicidae. Shell with medium spire, external or partly sixtieth to one-three-bundredth of an inch, and they move by covered by the mantle; genital aperture below the right pos
means of long cilia. Two ventral bands composed of regular terior tentacle; genital apparatus generally provided with a transverse rows of cilia are usually found. The head bears some dart-sac and multifid vesicles. Helix, British. Bulimus. especially large cilia. The cuticle which covers the body is here
Hem phillia. Berendtia. Cochlostyla. Rhodea.
and there raised into overlapping scales which may be prolonged mented with ribs; borders of aperture thin and not reflected; into bristles. An enlarged, frontal scale may cover the head, and radula with square teeth; genital ducts without accessory a row of scales separates the ventral ciliated areas from one
another, whilst two series of alternating rows cover the back and trial of Charles I. He was married four times, and died in July side. The body, otherwise circular in section, is slightly flattened 1654. ventrally. The mouth is anterior and slightly ventral; it leads His principal works, besides some volumes of sermons are-on into a protrusible pharynx armed with recurved teeth that can be the Nature and Use of Lots (1619), a curious treatise which led to his
being accused of favouring games of chance; Dissertatio de stylo everted. This leads to a muscular Novi Testamenti (1648); Cinnus, sive Adversaria miscellanea, in Во
oesophagus with a triradiate lumen, quibus Sacrae Scriplurac primo, deinde aliorum scriptorum, locis Xe.
which acts as a sucking pump and aliquam mullis lux redditur (165!), to which was afterwards sub
ha ends in a funnel-valve projecting joined Adversoria Posthuma; and his edition of Marcus Antoninus Vb
(1652), which, according to Hallam, is the earliest edition of any. is oval and formed of four rows of and, for the period at which it was written, possesses remarkable PL
large cells; it is separated by a merit. His collected works were published at Utrecht in 1698.
sphincter from the rectum, which GATCHINA, a town of Russia, in the government of St PetersSe
opens posteriorly and dorsally. burg, 29 m. by rail S. of the city of St Petersburg, in 59°34'N. and Sch...
The nitrogenous excretory appara- 30° 6' E. Pop. (1860) 9184; (1897) 14,735. It is situated in a
specics eyes. The muscles are simple application, embracing not only the defensive entrance ways into Sch..!
and unstriated and for the most part a fortified place, with which this article mainly deals, or the run longitudinally.
imposing architectural features which form the main entrances to The two ovaries lie at the level of palaces, colleges, monastic buildings, &c., but also the common Sa the juncture of the stomach and five-barred barrier which closes an opening into a field. The most
rectum. The eggs become very general distinction that can be made between “ door " and From Zeitschrift für Wissen- large, sometimes half the length of gate" is that of size, the greater entrance into a court containterheber Zoologico della Pop: the mother; they are laid amongst ing other buildings being the "gate," the smaller entrances
water weeds. The male reproductive opening directly into the particular buildings the “ doors," or Chaclonotus maximus, system is but little known, a small that of construction, the whole entrance way being a “gate" or Ehrb., ventral side. (After gland lying between the ovaries has gateway, the barrier which closes it a “door.” A further disZelinka.) Bo, Bristles surrounding it be, the Gastrotricha are berma
been thought to be a testis, and if tinction is drawn by applying "door " to the solid barriers or the mouth.
“ valves" of wood, metal, &c., made in panels and fitted to a ds, Dorsal bristles. phrodite.
framework, and “gatc" to an openwork structure, whether of hCi, Posterior lateral cilia. Zelinka classifies the group as fol. metal or wood (sec further Door and METAL-WORK). The Ke, Cuticular dome. lows:
ultimate origin of the word is obscure; the carly forms appear Mi, Oral cavity.
Sub-order 1.-EUICHTHYDINA with a IT, Lateral sensory hairs. forked tail.
with a palatalized initial letter, still surviving in such dialectical Pl, Cuticular plates, .(i.) Fam. Ichthydidae, without forms as " yate," or in Scots "yett." It is probably connected Sa, Dorsal bristle of the bristles. Genera: Ichthydium, Lepido- with the root of “get," in the sense either of " means of access derma.
or of" holding,"
Chaetonotidae, Sch, Plates. (ii.) Fam.
receptacle "; cf. Dutch gat, hole. There may be
with Se, Lateral bristles. bristles. Genera: Chaetonotus,
a connexion, however, with "gate,” now usually spelled gait," Vb, Point of union of cili- Chaetura.
a manner of walking, but originally a way, passage; cf. Ger. ated tract.
Sub-order 2.—APODINA, tail not Gasse, narrow street, lane. Ci, Anterior group of cilia. forked. Genera: Dasydytes, Gossca, The entrance through the enclosing walls of a city or fortificaoS, Ventral bristles of the Stylochaela. The genus Aspidiophorus recently
tion has been from the earliest times a place of the utmost described by. Voigt seems in some importance, considered architecturally, socially or from the point respects intermediate between Lepidoderma and Chaetonolus. of view of the military engineer. In the East the "gate" was Zelinkia and Philosyrtis are two slightly aberrant forms described and still is in many Mahommedan countries the central place of by Giard from certain diatomaceous sands. Altogether there must civic life. Here was the seat of justice and of audience, the most be some forty to fifty described species.
The group is an isolated one and shows no clear affinities with any important market-place, the spot where men gathered to receive of the great phyla. Those that are usually dwelt on are treated and exchange news. The references in the Bible to the gates of with the Rotilers and Nematoda and Turbellaria. LITERATURE.-A.C. Stokes, The Microscope (Detroit, 1887-1888);
the city in all these varied aspects are innumerable (cf. Gen. xix. c. Zelinka, Zeitschr. wiss. Zool. xlix., 1890, p. 209; M. Voigt: 1; Deut. xxv. 7; Ruth iv. 1; 2 Sam. xix. 8; 2 Kings vii. 1). Later Forschber. Plön. Th. ix., 1904, p. 1; A. Giard, c. R. Soc. Biol. lvi. the seat of justice and of government is transferred to the gate of pp. 1061 and 1063; E. Daday, Termes. Fuzetek. xxiv. p. 1; F. the palace of the king (cf. Dan. ii. 49, and Esther ii. 19), and this Zschokke, Denk. Schweiz. Ges. xxxvii. p. 109: S. Hlava, Zool. Anz. use is preserved to-day in the official title of the seat of governxxviii., 1905, p. 331.
(A. E. S.)
ment of the Turkish empire at Constantinople, the “ Sublime GATAKER, THOMAS (1574-1654), English divine, was born Porte," a translation of the Turkish Bab Aliy (bab, gate, and aliy, in London in September 1574, and educated at St John's College, high). A full account with many modern instances of Eastern Cambridge. From 1601 to 1611 he held the appointment of customs will be found in Sir Charles Warren's article" Gate "in Preacher to the society of Lincoln's Inn, which he resigned on accepting the rectory of Rotherhithe. In 1642 he was chosen a
The spelling" gait "is confined to this meaning--the only literary one surviving. In the form "
gate it appears dialectally in this member of the assembly of divincs at Westminster, and annotated sense and in such particular meanings as a right to run cattle on for that assembly the books of Isaiah, Jeremiah and Lamenta- common or private ground or as a passage way in mines. The printions. He disapproved of the introduction of the Covenant,
cipal survival is in names of streets in the north and midlands of and declared himself in favour of episcopacy. He was one of Castle Gate at Nottingham, Gallow Tree Gate at Leicester, and
England and in Scotland, e.g. Briggate at Leeds, Wheeler Gate and the forty-seven London clergymen who disapproved of the Canongate and Cowgate at Edinburgh.
Hastings's Dict. of Bible. For the "pylon,” the typical gate of | not always in such collective abundance in the fortified gateways Egyptian architecture, see ARCHITECTURE.
of the middle ages. Two massive towers flanked the actual The gates into a walled town or other fortified place were entrance and were linked across by an iron chain; over the necessarily in early times the chief points on which the attack | entrance (E) was a machicolation, further added to in time of concentrated, and the features, common throughout the ages, of war by a hoarding of timber; and an outer portcullis fell in flanking or surmounting towers and of galleries over the entrance front of the heavy iron-lined doors. On to the passage way way, are found in the Assyrian gate at Khorsabad (cf. 2 Chron. between the first and second doors opened a square machicolation xxvi. 9; 2 Sam. xviii. 24). With the coming of peaceful times to (G) from which the defenders in the upper chambers of the gate a city or the removal of the fear of sudden attack, the gateways could attack an enemy that had succeeded in breaking through would take a form adapted more for ready exit and entrance the first entrance or had been trapped by the falling of the first than for defence, though the possibility of defending them was portcullis. Another machicolation (1) opened from the roof in not forgotten. Such city gates often had separate openings front of the second portcullis and second door. So much for the for entrance and exit, and again for foot passengers and for gate itself; but before an attack could reach that point, the vehicles. The Gallo-Roman gate at Autun has four entrances, following defences had to be passed: an immense circular two just wide enough to admit carriages, and two narrow alleys barbican (A) protected the entrance across the moat and through for foot passengers. A fine example of a Roman city gate, dating the outer enceinle of the city. This entrance was flanked by a from the time of Constantine, is at Trèves. It is four storeys masked return of the wall (C), while palisades (P) still further high, with ornamental windows, and decorated with columns hampered the assailant in his passage across the " lists" to the on each storey. The two outer wings project beyond the central foot of the gate towers. Here sappers would find themselves part, the two entrance ways are 14 ft. wide, and could be closed by exposed to a fire from the loopholes and from the machicolated doors and a portcullis. The chambers in the storeys above were hoardings above them, while the projecting horns with which used for the purposes of civil administration. In more modern
The City times city gateways have often followed the type of the Roman triumphal arch, with a single wide opening and purely ornamental superstructure. On the other hand, the defensive gate formed by an archway entering as it were through a tower has been constantly followed as a type of entrance to buildings of an entirely peaceful character. A fine example of such a gateway, originally built for defence, is at Battle Abbey; this was built by Abbot Retlynge in 1338, when Edward III. granted a licence to fortify and crenellate the abbey. Such gateways are typical of Tudor palaces, as at St James's or at Hampton Court, and are the most common form in the colleges of Oxford and Cambridge. The Tom Gate at Christ Church, Oxford, with its surmounted domed bell tower, or the cupola resting on columns at Queen's College, Oxford, are further examples of the gate architecturally considered.
The changes the fortified gateway has undergone in construction and the varying relative importance it has held in the scheme
Fig. 1.-Plan of the Narbonne Gate of the city of Carcassonne. of defence follow the lines of development taken by the history the face of the towers terminated forced them to uncover themof FORTIFICATION AND SIEGECRAFT (9.0.). The following is a selves to a flanking fire from the indents in the main curtain on short sketch of the main stages in its history. A good example either side of the towers. of the Roman fortified city gate still remains at Pompeii. Here The later history of the gateway is merged in that of modern there is one passage way for vehicles, 14 ft. wide; this is open to fortification. The more elaborate the gate defences the greater the sky. The two footways on either side are arched, with was the inducement for the besieger to attack the walls, and openings in the centre on to the central way. The doors of the improvements in methods of siegecraft ultimately compelled the gate are on the city side, but a portcullis (cataracta) closed it defender to develop the enceinte from its medieval form of a ring on the country side. The gateways of the Roman permanent wall with flanking towers to the 17th century form of bastions, camps (castra staliva) were four in number, the porta praetoria curtains, tenailles and ravelins, all intimately connected in one and Decumana at either end, with principalis dexira and sinistra general scheme of defence. By Vauban's time there is little to on the side (see also CAMP). At Pevensey (Anderida) a small distinguish the position and defences of the gateways from the postern on the north side of the Roman walls was laid bare rest of the fortifications surrounding a town. A road from the in 1906–1907, in which the passage curves in the thickness of the country usually entered one of the ravelins, sinking into the wall, and from a width admitting two men abreast narrows so glacis, crossing the ditch of the ravelin and piercing the parapet that one alone could block it. Flanking towers or bastions almost at right angles to its proper direction (see fig. 2, which guarded the main entrances, while in front were built outworks, also shows a typical arrangement of minor communications of palisades, &c., to protect it; these were known as pro- such as ramps and staircases). From the interior of the ravelin castra or anlemuralia, and the entrances to these were placed it passed across the main ditch to a gate in the curtain of the so that they could be flanked from the main walls.
enceinte. The road was in fact artificially made to wind in such a In the desence of a fortified place the gate had not only to be way that it was kept under fire from the defences throughout, while protected from sudden surprise, but also had to undergo pro- the part of it inside the works was bent so as to place a covering tracted attacks concentrated upon it during a siege. Thus until mass between the enemy's fire and troops using the road for a the coming of gunpowder, the ingenuity of military engineers sortie. Thus the gate itself was merely a barrier against a coup was exhausted in accumulating the most complicated defences de main and to keep out unauthorized persons. In conditions round the gateways, and the strength of a fortified place could precluding the making of a breach in the walls, i.e. in surprises be estimated by the fewness of its gates. Viollet-le-Duc (Dict. and assaults de vive force, the gateway and accompanying de l'arch. du moyen âge, s.v. Porle) takes the Narbonne and Aude drawbridge continue to play their part in the 16th, 17th and gates (E. and W.) of Carcassonne as typical instances of this 18th centuries, but they seldom or never appear as the objectives complication. The following brief account of the Narbonne of a siege en règle. In Vauban's works, and those of most other Gate (fig. 1), one of the principal parts of the work on the fortifica- engineers, there was generally a postern giving access to the tions begun by Philip the Bold in 1285, will give some idea of floor of the main ditch, in the centre of the curtain escarp. The the varied means of defence, which may be found individually if I gates of Vauban's and later fortresses are strong hcavy wooden
doors, and the gateways more or less ornamental archways, where he lived till the outbreak of the War of Independence in exactly as in many private mansions of castellar form. In 1775, when he was named by Congress adjutant-general. In 1776 modern fortresses the gate of a detached fort or an enceinte de he was appointed to command the troops which had lately sureté is intended purely as a defence against an unexpected retreated from Canada, and in August 1777, as a result of rush. The usual method is to have two gates, the outer one a successful intrigue, was appointed to supersede General Philip lattice or portcullis of iron bars and the inner one a plate of hall-Schuyler in command of the Northern Department. In the two inch stcel armour, backed by wood and loopholed. The defenders battles of Saratoga (9.0.) his army defeated General Burgoyne, of the gate can by this arrangement fire from the inner loopholes who, on the 17th of October, was forced to surrender his whole through the outer gate upon the approaches, and also keep the army. This success was, however, largely due to the previous enemy under fire whilst he is trying to force the outer gate manquvres of Schuyler and to Gates's subordinate officers. The
intrigues of the Conway Cabal to have Washington superseded by Gates completely failed, but Gates was president for a time of the Board of War, and in 1780 was placed in chief command in the South. He was totally defeated at Camden, S.C., by Cornwallis on the 17th of August 1780, and in December was superseded by Greenc, though an investigation into his conduct terminated in acquittal (1782). He then retired to his Virginian estate, whence he removed to New York in 1790, alter emancipaling his slaves and providing for those who needed assistance. He died in New York on the roth of April 1806.
GATESHEAD, a municipal, county and parliamentary borough of Durham, England; on the S. bank of the Tyne opposite Newcastle, and on the North Eastern railway. Pop. (1891) 85,692; (1901) 109,888. Though one of the largest towns in the county, neither its strccts nor its public buildings, except perhaps its ecclesiastical buildings, have much claim to architectural beauty. The parish church of St Mary is an
ancient cruciform cdifice surmounted by a lofty tower; but Fig. 2.- Plan of Gate Arrangements of an 18th Century Fortress.
extensive restoration was necessitated by a fire in 1854 which
destroyed a considerable part of the town. The town-hall, public itself. The ditches are crossed either by drawbridges or by ramps library and mechanic's institute are noteworthy buildings. leading the road down to the floor of the ditch.
Education is provided by a grammar school, a large day school The “gate" as a barrier to be removed and as an entrance for girls, and technical and art schools. There is a service of to be passed is of constant occurrence in figurative language stcam trams in the principal streets, and three fine bridges and in symbolical usage. The gates of the temple of Janus (9.0.) connect the town with Newcastle-upon-Tyne. There are large at Rome stood open in war and closed in peace. The pylon of iron works (including foundries and factories for engines, boilers, ancient Egypt had a symbolical meaning in the Book of the Dead, chains and cables), shipbuilding yards, glass manufactories, and religious significance attaches to the torii, one of the outward chemical, soap and candle works, brick and tile works, breweries signs of the Shinto religion in Japan, the Buddhist toran, and to and tanneries. The town also contains a depot of the North the Chinese pai-loo, the honorific gateways erected to ancestors. Eastern railway, with large stores and locomotive works. ExtenThe gates of heaven and hell, the gates of death and darkness, sive coal mines exist in the vicinity; and at Gateshead Fell are the wide and narrow gates that lead to destruction and life large quarries for grindstones, which are much esteemed and are (Matt. vii. 13 and 14), are familiar metaphorical phrases in the exported to all parts of the world. Large gas-works of the Bible. In Greek and Roman legend dreams pass through Newcastle and Gateshead Gas Company are also situated in the gates of transparent horn is true, if deceptive and false borough. The parliamentary borough returns one member. through opaque gates of ivory (Hom. Od. xix. 560 sq.; Virg. The corporation consists of a mayor, 9 aldermen, and 27 Aen. vi. 893).
(C. We.) councillors. Area, 3132 acres. GATEHOUSE. In the second half of the 16th century in Gateshead (Gateshewed) probably grew up during late Saxon England the entrance gateway, which formed part of the principal times, the mention of the church there in which Bishop Walcher front of the earlier feudal castles, became a detached feature was murdered in 1080 being the first evidence of settlement. attached to the mansions only by a wall enclosing the entrance The borough probably obtained its charter during the following court. The gatehouse then constituted a structure of some century, for Hugh de Puiset, bishop of Durham (1153-1195), importance, and included sometimes many rooms as at Stanway confirmed to his burgesses similar rights to those of the burgesses Hall, Gloucestershire, where it measures 44 st. by 22 ft. and has of Newcastle, freedom of toll within the palatinate and other three storeys; at Westwood, Worcestershire, it had a frontage privileges. The bishop had a park here in 1348, and in 1438 of 54 ft. with two storeys; and at Burton Agnes, Yorkshire, Bishop Nevill appointed a keeper of the " tower.". The position it was still larger and was flanked by great octagonal towers of the town led to a struggle with Newcastle over both fishing at the angles and had threc storeys. At a later period smaller and trading rights. An inquisition of 1322 declared that the accommodation was provided so that it virtually became a lodge, water of the Tyne was divided into three parts: the northern, but being designed to harmonize with the mansion it presented belonging to Northumberland; the southern to Durham; and sometimes a monumental structure. On the continent of the central, common to all. At another inquisition held in 1336 Europe the gatehouse forms a much more important building, the men of Gateshead claimed liberty of trading and fishing as it formed part of the town fortifications, where it sometimes along the coast of Durham, and freedom to sell their fish where defended the passage of a bridge across the stream or moat. they would. In 1552, on the temporary extinction of the There are numerous examples in France and Germany. diocese of Durham, Gateshead was attached to Newcastle, but 1. GATES, HORATIO (1728-1806), American general, was born in 1554 was regranted to Bishop Tunstall. As compensation at Maldon in Essex, England, in 1728. He entered the English the bishop granted to Newcastle, at a nominal rent, the Gateshead army at an early age, and was rapidly promoted. He accom- salt-meadows, with rights of way to the High Street, thus panied General Braddock in his disastrous expedition against abolishing the toll previously paid to the bishop. During the Fort Duquesne in 1755, and was severely wounded in the battle next century Bishop Tunstall's successors incorporated ncarly of July 9; and he saw other active service in the Seven Years' | all the various trades of Gateshead, and Cromwell continued War. After the peace of 1763 he purchased an estate in Virginia, I this policy. The town government during this period was by