the plateaus belong to the Brie, a fertile well-wooded district of | farming is prosperous, the town of Houdan giving its name to a wella clayey character. In the south lie the dry sandy district of the Fontainebleau sandstones and part of the region known as the Gâtinais. The climate is rather more "continental" than that of Paris-the summers warmer, the winters colder; the annual rainfall does not exceed 16 in. There is a striking difference in temperature between the south of the department, where the famous white grape (chasselas) of Fontainebleau ripens, and the country to the north of the Marne,-this river marking pretty exactly the northern limit of the vine.

known breed of fowls. Forests occupy about 190,000 acres, the largest being that of Rambouillet (about 32,000 acres). Oak, hornbeam, birch and chestnut are the commonest trees. Building, paving and mill stones, gypsum, cement, &c., are produced by the department which is very rich in quarries. There are mineral springs at Enghien and Forges-les-Bains. The most important industrial establishments are the national porcelain factory at Sèvres; the government powder-mills of Sevran and Bouchet; paper-muls, especially those of Essonnes and its vicinity, which are among the most important in Europe; textile works, flour-mills, foundries and engineering, metallurgical or railway works at Evry-Petit-Bourg, Villeneuve-St Georges (pop. 9508) and elsewhere; agricultural implement factories at Dourdan and elsewhere; sugar-refineries and distilleries; crystal works (Meudon), laundries, large printing establishments, close to Paris; factories for chemical products, candles, hosiery, perfumery, shoes and buttons; zinc-works, sawmills. Seine-et-Oise exports chiefly the products of its farms and quarries. Its imports include coal, raw material for its industries, wine, kaolin and wood.

Southern) traverse the department, but most of the lines belong to The railways of all the great companies of France (except the those of the Western and Northern systems. The Seine and the and the canals of Ourcq and Chelles provide about 120 m. of waterway. Seine-et-Oise is divided into six arrondissements (Versailles, Corbeil, Étampes, Mantes, Pontoise, Rambouillet) with 37 cantons and 691 communes. It forms the diocese of Versailles and regions of the II., III., IV. and V. army corps, the troops in its territory part of the educational circumscription (académic) of Paris and of the being under the command of the military government of Paris. Its court of appeal is also at Paris.

The wheat and oats of Brie are especially esteemed; potatoes, sugar beet, mangel-wurzel and green forage are also important crops, and market gardening flourishes. Provins and other places are wellknown for their roses. The cider and honey of the department are of good quality Thousands of the well-known Brie cheeses are manu. factured, and large numbers of calves, sheep and poultry are reared. The forests (covering a fifth of the surface) are planted with oak, beech, chestnut, hornbeam, birch, wild cherry, linden, willow, poplar and conifers. Best known and most important is the forest of Fontainebleau. Large areas are devoted to game-preserves. Excellent freestone is quarried in the department, notably at ChâteauLandon in the valley of the Loing, mill-stones at La Ferté-sous-Oise, Jouarre, the Fontainebleau sandstone is used for pavements, and the white sand which is found along with it is in great request for the manufacture of glass. Along the Marne are numerous gypsum quarries; lime-kilns occur throughout the department; and peat is found in the valleys of the Ourcq and the Voulzie. Beds of common clay and porcelain clay supply the potteries of Fontainebleau and Montereau. Other industrial establishments are numerous large flour-mills, notably those of Meaux, the chocolate works of Noisiel. sugar factories, alcohol distilleries, paper-mills (the Jouarre paper. mill manufactures bank-notes, &c., both for France and for foreign markets), saw-mills, printing works (Coulommiers, &c.) and tanneries. Much of the motive-power used is supplied by the streams. Paris is the chief outlet for the industrial and agricultural products of the department. Coal and raw material for the manufactures are the chief imports. The Seine, the Yonne, the Marne, and the Grand Morin are navigable, and, with the canals of the Loing and the Ourcq and those of Chalifert, Cornillon and Chelles, which cut off the windings of the Marne, form a total waterway of over 200 m. Seineet-Marne has 5 arrondissements (Melun, Coulommiers, Fontainebleau, Meaux, Provins), 29 cantons and 533 communes. It forms the diocese of Meaux (archiepiscopal province of Paris), and part of the region of the V. army corps and of the académie (educational circumscription) of Paris. Its court of appeal is at Paris. Melun, the capital, Meaux, Fontainebleau, Coulommiers, Provins, Nemours and Montercau (qq.v.), are the more important towns in the department. Among other interesting places are Lagny (pop. 5302), with an abbeychurch of the 13th century; Brie-Comte Robert, with a church of the early 13th century; Ferrières, with a fine château built in 1860 by Baron Alphonse Rothschild; Moret-sur-Loing, which preserves fortifications dating from the 15th century including two remarkable gateways; St Loup-de-Naud, with a church of the first half of the 12th century; Jouarre, where there is a church of the 15th century, period; and Vaux-le-Vicomte with the famous château built by built over a crypt containing workmanship of the Merovingian Fouquet, minister of Louis XIV.

SEINE-ET-OISE, a department of northern France, formed in 1790 of part of the old province of Île-de-France, and traversed from south-east to north-west by the Seine, which is joined by the Oise. Pop. (1906) 749,753. Area, 2184 sq. m. It is bounded by the departments of Seine-et-Marne on the E., Loiret on the S., Eure-et-Loir on the W., Eure on the N.W. and Oise on the N. It encloses the department of Seine. The Epte on the north-west is almost the only natural boundary on the department. The streams (all belonging to the basin of the Seine) are: on the right the Yères, the Marne, the Oise and the Epte, and on the left the Essonne (joined by the Juine, which passes Etampes), the Orge, the Bièvre and the Mauldre. Seine-et-Oise belongs in part of the tableland of Beauce in the south and to that of Brie in the east. In the centre are the high wooded hills which make the charm of Versailles, Marly and St Germain. But it is in the north-west, in the Vexin, that the culminating point (690 ft.) is reached, while the lowest point, where the Seine leaves the department, is little more than 40 ft. above the sea. The mean temperature is 51° F.

Seine-et-Oise is a flourishing agricultural and horticultural department. Wheat, oats, potatoes and sugar-beet are important crops. Versailles, Rambouillet, Argenteuil are among the numerous market-gardening and horticultural centres, and wine is grown at Argenteuil and in other localities on the right bank of the Seine. Milch-cows and draught-oxen are the chief livestock, and poultry

capital, Corbeil, Sèvres, Étampes, Mantes, Pontoise, Rambouillet, The most notable towns in the department are Versailles, the Argenteuil, Poissy, St Cloud, St Cyr, St Germain-en-Laye, Meudon, Montmorency, Rueil and Marly-le-Roi (see separate articles). Other places of interest are Montfort-l'Amaury, which has a Renaissance church with fine stained glass, a gateway of the 16th century and a ruined château once the seat of the powerful family of Montfort; Montlhéry, which preserves the keep (13th century) and other ruins of a celebrated fortress which commanded the road from Paris to Orléans; Roche-Guyon, seat of the family of that name, which has two châteaus, one a feudal stronghold, the other also medieval but altered in the 18th century; Vigny, with a Gothic château of the 15th century; Ecouen, where there is a château of the 16th century once the property of the Condé family, now a school for daughters of members of the Legion of Honour; Dampierre, which has a château Lorraine; Maisons-Laffitte (pop. 8117), with a château of the same of the 17th century once the property of Charles, Cardinal of period once belonging to the family of Longueil. The château of Malmaison (18th century) is famous as the residence of the Empress Joséphine.

Of the churches of the department, which are very numerous mention may be made of those of Jouy-le Moutier (11th and 12th centuries); Beaumont-sur-Oise (13th century); Taverny (12th and 13th centuries); Longpont (remains of an abbey-church dating from the 11th to the 13th centuries). Near Cernay-la-Ville are interesting with stalls which are among the oldest in France and the tombs of remains of a Cistercian abbey and near Lévy-St-Nom those of the abbey of Notre-Dame de la Roche, including a church (13th century) the Lévis-Mirepoix family.

SEINE-INFÉRIEURE, a department of the north of France, formed in 1790 of four districts (Norman Vexin Bray, Caux and Roumois) belonging to the province of Normandy Pop. (1906) 863,879. Area 2448 sq. m Seine-Inférieure is bounded N.W. and N. by the English Channel for a distance of 80 m., N.E by Somme, from which it is separated by the Bresle, E. by Oise, S. by Eure and the estuary of the Seine, which separates it from Calvados. It is divided almost equally between the basin of the Seine in the south and the basins of certain coast streams in the north. The Seine receives from the right hand before it reaches the department the Epte and the Andelle from the Bray district, and then the Darnétal, the Cailly, the Austreberthe, the Bolbec and the Lézarde. The main coast streams are the Bresle (which forms the ports of Eu and Tréport), the Yères, the Arques or Dieppe stream (formed by the junction of the Varennes, the Béthune and the Eaulne), the Scie, the Saane, the Durdent. The Pays de Caux, the most extensive natural division, is a system of plateaus separated by small valleys, terminating along the Seine in high bluffs and towards the sea in steep chalk cliffs 300 to 400 ft. high, which are continually being caten away and transformed into beds of shingle. The Bray district in the south-east is a broad valley of denudation formed by the sea as it retired, and traversed by valleys covered with excellent

pasture. The highest point (about 800 ft.) is on the eastern | seisin in deed. Seisin is now confined to possession of the border of the department. In the comparatively regular outline freehold, though at one time it appears to have been used for of the coast there are a few breaks, as at Le Tréport, Dieppe, simple possession without regard to the estate of the possessor.' St Valery-en-Caux, Fécamp and Havre, the Cap de la Hève, Its importance is considerably less than it was at one time, which commands this last port, and Cape Antifer, 12 or 13 m. owing to the old form of conveyance by feoffment with livery of farther north. Le Tréport, Dieppe, Veules, St Valery, Veulettes, seisin having been superseded by a deed of grant (see FEOFFFécamp, Yport, Etretat and Ste Adresse (to mention only the MENT), and the old rule of descent from the person last seised more important) are fashionable watering-places. Forges-les- having been abolished in favour of descent from the purchaser. Eaux (in the cast of the department) has cold chalybeate springs At one time the right of the wife to dower and of the husband of some note. The winter is not quite so cold nor the summer to an estate by curtesy depended upon the doctrine of seisin. so hot as in Paris, but the average temperature of the year is The Dower Act (1833-1834), however, rendered the fact of the higher. The rainfall at Rouen is 28 in. per annum, increasing seisin of the husband of no importance, and the Married Women's towards Dieppe. Property Act 1882 practically abolished the old law of curtesy. Primer seisin was a feudal burden at one time incident to the king's tenants in capite, whether by knight service or in socage. It was the right of the crown to receive of the heir, after the death of a tenant in capite, one year's profits of lands in possession and half a year's profits of lands in reversion. The right was abandoned by the act abolishing feudal tenures (12 Car. II. C. 24, 1660).

In general the department is fertile and well cultivated. Along the Seine fine meadow-land has been reclaimed by dyking; and sandy and barren districts have been planted with trees, mostly with oaks and beeches, and they often attain magnificent dimensions, especially in the forest of Arques and along the railway from Rouen to Dieppe; Pinus sylvestris is the principal component of the forest of Rouvray opposite Rouen. The forest of Eu covers 36 sq. m. in the north-east. Of the arable crops wheat and oats are the principal, rye, flax, colza, sugar beet and potatoes being also of importance. Milch cows are kept in great numbers especially in the Bray district, and Gournay butter and Gournay and Neufchâtel cheese are in repute. The farms of the Caux plateau are each surrounded by an earthen dyke, on which are planted forest trees, generally beech and oak. Within the shelter thus provided apple and pear trees grow, which produce the cider generally drunk by the inhabitants. With the exception of a little peat and a number of quarries, Seine-Inférieure has no mineral source of wealth; but manufacturing and especially the textile industry is well developed. Rouen is the chief centre of the cotton trade, which comprises spinning and the weaving of rouenneries, indiennes (cotton prints), cretonnes and other cotton goods. Elbeuf is the centre of woollen manufacture. Flax-spinning, the dyeing and printing of fabrics and other accessory industries also employ many hands. Engineering works, foundries and iron ship-building yards are found at Havre and Rouen. Wooden ships are also built at Havre, Rouen, Dieppe and Fécamp. Other establishments of importance are the national tobacco-factories at Dieppe and Havre, sugar-refineries, distilleries, glass-works, potteries, paper works, soapworks, chemical works, flour-mills, oil-factories, leather works, &c. The fisheries are the great resource for the inhabitants of the seaboard. Fécamp, which plays a very important part at the Newfound land fisheries, sends large quantities of cod, herrings, mackerel, &c., into the market; Dieppe supplies Paris with fresh fish; St Valery sends boats as far as Iceland. The principal ports for foreign trade are Havre, Rouen and Dieppe.

The chief imports of the department are cotton, wool, cereals, hides, coffee, timber and dye-woods, indigo and other tropical products, coal, petroleum, &c. The exports include industrial and dairy products, Seine-Inférieure is served principally by the Western railway, but the Northern railway also has several lines there. The Seine and other rivers provide 85 m. of navigable waterway. The canal of Tancarville from Quillebeuf to Havre is about 15 m. long, that from Eu to Tréport about 2 m. The department is divided into five arrondissements (Rouen, Dieppe, Havre, Neufchâtel and Yvetot) 55 cantons and 760 communes. It forms the diocese of the archbishopric of Rouen and part of the region of the III. army corps and of the académie (educational division) of Caen. Its court of appeal is at Rouen, the capital.

Rouen, Havre and Dieppe and in a lesser degree, Elbeuf, Fécamp, Harfleur, Lillebonne, Yvetot, Eu, Le Tréport, Aumale, Etretat. Bolbec, Barentin and Caudebec-en-Caux (see separate articles) are noteworthy towns for commercial, architectural or other reasons. The following places are also of architectural interest. St Martin-de Boscherville, where there are remains of an important abbey including a fine church in the Romanesque style of the early 12th century and a Gothic chapter-house of the latter half of the 12th century; Valmont, which has fine ruins (16th century) of the choir of a Cistercian abbey-church; Varengeville, well known for the manor (16th century) of Jacques Ango (see DIEPPE); Graville-Ste Honorine, with a Romanesque church and other remains of an ancient abbey: Montivilliers, which has a fine abbey-church of the 11th, 12th and 16th centuries; and Arques, Boos, Martainville, Mesnières and Tancarville which have old châteaus of various periods.

SEISIN (from M. Eng. saysen, seysen, in the legal sense of to put in possession of, or to take possession of, hence, to grasp, to seize; the O. Fr. seisir, saisir, is from Low Lat. sacire, generally referred to the same source as Goth. satjan, O. Eng. sellan, to put in place, set), the possession of such an estate in land as was anciently thought worthy to be held by a free man (Williams, On Seisin, p. 2). Seisin is of two kinds, in law and in deed. Seisin in law is where lands descend and the heir has not actually entered upon them; by entry he converts his seisin in law into

In Scots law the corresponding term is "sasine." Like seisin in England, sasine has become of little legal importance owing to modern legislation. By an act of 1845 actual sasine on the lands was made unnecessary. By an act of 1858 the instrument of sasine was superseded by the recording of the conveyance with a warrant of registration thereon.

SEISMOMETER (from Gr. σetouós, earthquake, and μérpov, a measure). This name was originally given to instruments designed to measure the movement of the ground during earthquakes (q.v.). Observations have shown that, in addition to the comparatively great and sudden displacements which occur in earthquakes, the ground is subject to other movements. Some of these, which may be called "earth-tremors," resemble earthquakes in the rapidity with which they occur, but differ from earthquakes in being imperceptible (owing to the smallness of the motion) until instrumental means are used to detect them. Others, which may be called "earth-tiltings," show themselves by a slow bending and unbending of the surface, so that a post stuck in the ground, vertical to begin with, does not remain vertical, but inclines now to one side and now to another, the plane of the ground in which it stands shifting relatively to the horizon. No sharp distinction can be drawn between these classes of movements. Earthquakes and earth-tremors grade into one another, and in almost every earthquake there is some tilting of the surface. The term "seismometer may conveniently be extended (and will here be understood) to cover all instruments which are designed to measure movements of the ground.

"

Seismo.

scope.

Popularly it is supposed that earthquake recorders are instruments so sensitive to slight vibrations that great care is necessary in selecting a site for their installation. Although this supposition is correct for a certain class of apparatus, as for example that which will record rapid elastic vibrations produced by the movement of a train a mile distant, it is far from being so for the ordinary apparatus employed by the seismologist. What he usually aims at is either to record the more or less rapid movements of the ground which we can feel, or the slow but large disturbances which do not appeal to our unaided senses. Generally speaking, the instruments used for these purposes are not disturbed by the vibrations resulting from ordinary traffic. In almost every household something may be found which will respond to a gentle shaking of the ground. Sometimes it is a loosely-fitting shutter or window. frame, a hanging drawer-handle, or a lamp-shade which will rattle; the timbers in a roof may creak, or a group of wine-glasses with their rims in contact may chatter. Any of these sounds may call attention to movements which otherwise would pass unnoticed. Specially arranged contrivances which tell us that the ground has been shaken are called seismoscopes or earthquake indicators. A small column, as for example a lead pencil standing on end, or a row of pins propped up against suitable supports, or other bodies which are easily overturned, may be used as seismoscopes. Experience, however, has

1 Up to the middle of the 15th century "seisin" was applied to chattels equally with freeholds, the word "possessed" being rarely used. In course of time the words acquired their modern meaning. See F. W. Maitland, Seisin of Chattels," Law Quarterly Review, vol. 1. p. 324 and "The Mystery of Seisin," Law Q. R. ii. 481. Pollock and Maitland, Hist. Eng. Law, vol. ii. 29 seq.; Fry, L. J., in Cochrane v. Moore (1890), 25 Q.B.D. 57.

by means of simple formulae calculate quantities closely agreeing
with those obtained from the seismogram. For example, if a body,
say a coping-stone, has been thrown horizontally through a distance
a, and fallen from a height b, the maximum horizontal velocity with
which it was projected equals (ga2/2b); or if the height of the
centre of gravity of a column like a gravestone above the base on
which it rests is y, and x is the horizontal distance of this centre
from the edge over which it has turned, then the acceleration or
suddenness of motion which caused its overthrow is measured, as
pointed out by C. D. West, with fair accuracy by gx/y.
To measure vertical motion, which with the greater number of
earthquakes is not appreciable, a fairly steady mass to which a
multiplying light-writing index can be attached is ob-
Gray's
tained from a weight carried on a lever held by any
seismo-
form of spring in a horizontal position. Such an arrange-
graph.
ment, for which seismologists are indebted to Professor
T. Gray, is shown in fig. 6, in which B is the mass used as the steady
point. This, when supported as shown, can be arranged to have
an extremely slow period of
vertical motion, and in this
respect be equivalent to a
weight attached to a very
long spring, an alternative
which is, however, impracti
cable. The value of these
records, as is the case with
other forms of seismographs,
is impaired by pronounced
tiltings of the ground.

Instru ments to

FIG. 6.

which have originated at great distances, but for local disturbances, even if the bob of the pendulum acts as a steady point, the highly multiplied displacements are usually too great to be recorded.

Fibre

On Needle

Mirror

In Japan, Germany, Austria, England and Russia horizontal pendulums of the von Rebeur-Paschwitz type are employed, which by means of levelling screws are usually adjusted to have a natural period or double swing of from 15 to 30 seconds. These pendulums are usually small. The swinging arm or boom is from 4 to 8 in. long horizontally, and carries at its extremity a weight of a few ounces. A simple form, which is sometimes referred to as a conical pendulum, may be constructed with a large sewing needle carrying a galvanometer mirror, suspended by means of a silk or quartz fibre as shown in fig. 7. To avoid the possibility of displacements due to magnetic influences, the needle may be replaced by a brass or glass rod. The adjustment of the instrument is effected by means of screws in the bed-plate, by turning which the axis oo" may be brought into a position nearly vertical. As this position is approached the period of swing becomes greater and greater, and sensibility to slight tilting at right angles to the plane of o'o'm is increased. The movements of the apparatus, which when complete should consist of two similar pendulums in planes at right angles to each other, are recorded by means of a beam of light, which, after reflection from the mirror or mirrors, passes through a cylindrical lens and is focussed upon a moving surface of photographic paper. The more distant this is from the pendulum the greater is the magnification of the angular movements of the mirror. With a period of 18 seconds, and the record-receiving paper at a distance of about 15 ft., a deflection of 1 millimetre of the light spot may indicate a tilting of part of a second of arc, or I in. in 326 miles. Although this high degree of sensibility, and even a sensibility still higher, may be required in connexion with investigations respecting changes in the vertical, it is not necessary in ordinary seismometry. A very sensitive modified von Rebeur instrument was employed by O. Hecker in his measurement of the variation in the vertical and of tidal earth tremors.

FIG. 7.

A type of instrument which has sufficient sensibility to record the various phases of unfelt earthquake motion, and which, at the suggestion of a committee of the British Association, has been adopted at many observatories throughout the world, is shown in fig. 8. With an adjustment to give a 15-second period, a deflection

Lamp

Bromide

Mirror

Stand

Boom

Paper..

Balance Weight

Masonry
Column

Table

We next turn to types of instruments employed to record earthquakes which have radiated from their origins, where they may have been violent, to such distances that their movements are no longer perceptible. In these instruments the same principles are followed as in the construction of horizontal pendulums, the chief difference being that the so-called steady mass is arranged to have a much longer period than that required when recording perceptible earthquakes. Instruments record dis largely employed for this purpose in Italy are ordinary laat earthOne at Catania pendulum seismographs as in fig. 2. quakes. consists of a weight of 300 kilos suspended by a wire 25 metres in length, the movements of which by means of writing indexes are multiplied 12.5 times. With pendulums of shorter of 1 mm. at the outer end of the boom corresponds to a tilting length, say 2 metres, it is necessary to have a multiplication 80 to 100 fold by a double system of very light levers, in order to render of the bed-plate of o".5, or 1 in. in 6.4 m. The record is obtained This by the light from a small lamp reflected downwards by a mirror so the extremely slight tilting of their support perceptible. as to pass through a slit in a small plate attached to the outer end arrangement, as devised by Professor G. Vicentini of Padua, will yield excellent diagrams of the gentle undulations of earthquakes of the boom. The short streak of light thus obtained moves with