Analyses of the two classes of hydraulic lime are as follows:—Chaux de Theil.Per cent.Blue Lias.Per centInsoluble silicious matter0.32.39Silica (SiO2)21.714.17Alumina (Al2O3)1.86.79Ferric oxide (Fe2O3)0.62.34Lime (CaO)74.063.43Magnesia (MgO)0.71.54Sulphuric anhydride (SO3)0.31.63Carbonic anhydride (CO2)}0.63.64Water (H20)2.69Alkalis and loss· ·1.38——————100.0100.00Hydraulic lime contains a good deal of uncombined lime, and has to be slaked before it is used as a cement. In France this slaking is conducted systematically by the makers, the freshly burned lime being sprinkled with water and stored in large bins where slaking proceeds slowly and regularly until the whole of the surplus uncombined lime is slaked and rendered harmless, while the cementitious compounds, notably tricalcium silicate, remain untouched. In English practice hydraulic lime is slaked by the user. Seeing that regular and perfect slaking is more easily attained when working systematically on a large scale and by storing the material for a long period, the French method is the better and more rational. The product may then be regarded as a cement of the Portland class mixed with slaked lime. When gauged with water and made into a mortar it sets slowly, but ultimately becomes almost as strong as Portland cement. Its slow setting is an advantage for some purposes,e.g.for foundations and abutments where settlements may occur. The structure is free to take its permanent position before the lime sets, and cracks are thus avoided. A case in point is the employment of hydraulic lime in place of Portland cement as grouting outside the cast-iron tubes used for lining tunnels made by the shield system.
Analyses of the two classes of hydraulic lime are as follows:—
Hydraulic lime contains a good deal of uncombined lime, and has to be slaked before it is used as a cement. In France this slaking is conducted systematically by the makers, the freshly burned lime being sprinkled with water and stored in large bins where slaking proceeds slowly and regularly until the whole of the surplus uncombined lime is slaked and rendered harmless, while the cementitious compounds, notably tricalcium silicate, remain untouched. In English practice hydraulic lime is slaked by the user. Seeing that regular and perfect slaking is more easily attained when working systematically on a large scale and by storing the material for a long period, the French method is the better and more rational. The product may then be regarded as a cement of the Portland class mixed with slaked lime. When gauged with water and made into a mortar it sets slowly, but ultimately becomes almost as strong as Portland cement. Its slow setting is an advantage for some purposes,e.g.for foundations and abutments where settlements may occur. The structure is free to take its permanent position before the lime sets, and cracks are thus avoided. A case in point is the employment of hydraulic lime in place of Portland cement as grouting outside the cast-iron tubes used for lining tunnels made by the shield system.
Roman Cementis another cement of the Portland class which came into use shortly before the manufacture of artificial Portland cement was attempted. It is still in use, though only for special purposes where a quick-setting material is required. It is made from septaria nodules which are dredged up on the Kent and Essex coasts and consist of about 60% of calcium carbonate mixed with clay, the mass being sufficiently indurated to remain coherent under water. The nodules are not prepared in any way, but simply burned at a moderate red heat.
The resulting cement varies somewhat in composition, but approximates to the following figures:—Per cent.Insoluble silicious matter5.86Silica (SiO2)19.62Alumina (Al203)10.30Ferric oxide (Fe2O3)7.44Manganese dioxide (MnO2)1.57Lime (CaO)44.54Magnesia (MgO)2.92Sulphuric anhydride (SO3)2.61Carbonic anhydride (CO2)3.43Water (H2O)0.25Alkalis and loss1.46———100.00The most characteristic constituent is the oxide of iron, which gives the cement a reddish colour, and the presence of manganese also differentiates Roman from Portland cement, which rarely contains appreciable quantities of that element. The high percentage of alumina causes the cement to be quick-setting, and it becomes hard in about five minutes. It resists the action of water, salt or fresh, very well, and is therefore useful in situations where the work is likely to be submerged immediately after it has been put in place.
The resulting cement varies somewhat in composition, but approximates to the following figures:—
The most characteristic constituent is the oxide of iron, which gives the cement a reddish colour, and the presence of manganese also differentiates Roman from Portland cement, which rarely contains appreciable quantities of that element. The high percentage of alumina causes the cement to be quick-setting, and it becomes hard in about five minutes. It resists the action of water, salt or fresh, very well, and is therefore useful in situations where the work is likely to be submerged immediately after it has been put in place.
The termNatural Cementsis applied to cements made by burning mixtures of clay and carbonate of lime naturally occurring in approximately suitable proportions. They may be regarded as badly-mixed Portland cements, and need no special description. American “natural” cements are of a somewhat different class. They are usually made from a silicious limestone containing magnesia, and are comparatively lightly burned.
The following analysis is typical of a cement of this kind:—Per cent.Silica (SiO2)24.30Alumina (Al203)7.22Ferric oxide (Fe2O3)5.06Lime (CaO)33.70Magnesia (MgO)20.94Water, carbonic anhydride, and loss8.78———100.00These irregular cements of the Portland class are good building materials for ordinary purposes, but are not so suitable as good artificial Portland cement for heavy and important undertakings.
The following analysis is typical of a cement of this kind:—
These irregular cements of the Portland class are good building materials for ordinary purposes, but are not so suitable as good artificial Portland cement for heavy and important undertakings.
Passow Cementis a recent product which is in a class by itself. It is made by granulating blast furnace slag of suitable composition and finely grinding the product, either alone or with an admixture of about 10% of Portland cement clinker. It differs from ordinary slag cement (see above) in that it is not a pozzuolanic cement depending on the interaction of granulated slag and lime. The particular method of granulating slag for Passow cement produces a material which setsper seand attains a strength comparable with that of Portland cement. Passow cement has been successfully made from slag of different compositions in Germany, England and America.
The chief use of hydraulic cements, whether of the pozzuolanic or Portland class, is to act as an adhesive material in work which is to be exposed to water. No doubt in times of remote antiquity it was found that the jointing of masonryUses of hydraulic cements.which was to be immersed required the use of a cement indifferent to the action of water. Ordinary mortar failed in such positions; mortar made from lime prepared from limestones or chalks containing a little clay was found to stand; mortar made from lime mixed with trass or similar active silicious material was also found to stand. On this observation rests the whole of the present enormous employment of hydraulic cements. It was a natural transition to utilize these cements not merely for jointing masonry but also for making concrete, and the only reason why hydraulic cements, as distinct from cements which are not hydraulic (e.g.ordinary mortar), are used for the latter purpose is their great mechanical strength. Their use in above-water work is checked by the low price of common brick. Even in such work, where it would be thought that masses of burnt clay would be the cheapest conceivable material, concrete is at least on level terms with its rival. It must be remembered that one of the great advantages of concrete is that five-sixths of its total mass may be provided from local sand and gravel, on which no carriage has to be paid. The cement, on which alone freight is to be reckoned, converts these from loose incoherent material into a solid stone. Thus it comes about that the largest use of cement is for manufacturing concrete for dock and harbour work, and for the making of foundations. It is also employed for the building of light bridges, floors, and pipes constructed of cement mortar disposed round a skeleton of iron rods. Such composite structures take advantage at once of the high tensile strength of iron and of the high compressive strength of cement mortar. (See alsoConcrete.)
Good hydraulic cements are highly permanent materials provided certain conditions be observed. It might be supposed that hydraulic cements from their nature would be indifferent to the action of water, but this is only true if the structures of which they form part are sufficiently compact. In this case the action of the water is checked by the film of carbonate of lime which eventually forms oh the surface of calcareous cement. This, together with the compactness of the mortar, hinders the ingress and egress of water, and prevents the dissolution and ultimate destruction of the cement. But where the concrete or mortar is not well made and is porous, the continual passage of water through it will gradually break up and dissolve away the calcareous constituents of the cement until its strength is utterly destroyed. This destructive action is increased if the water contains sulphates or magnesium salts, both of which act chemically on the calcareous constituents of the cement. As sea-water contains both sulphates and magnesium salts, it is especially necessary in concrete for harbour work to take every care to produce an impervious structure. There are various minor external causes for the failure and ultimate destruction of cement mortar and concrete, but their discussion is a matter for the specialist. Failure from inherent vice in the cement has been already touched on; it can always be traced to want of skill and care in manufacture.
Calcium Sulphate Cements.—Under this term are comprehended all cements whose setting properties primarily depend on the hydration of calcium sulphate. They include plaster of Paris, Keene’s cement and many variants of these two types. The raw material is gypsum (q.v.). This may be almost chemically pure, when it is generally used for Keene’s cement; or it may contain smaller or greater quantities of impurities, in which case it is suitable for the preparation of cements of the plaster of Paris class. The mode of preparation is to calcine the gypsum at temperatures which depend on the class of cement to be produced. If plaster of Paris is to be made, calcination is carried out at about 204° C. (= 400° F.); at this temperature, gypsum, CaS04·2H20, loses three-quarters of its combined water and becomes 2CaSO4·H20. If a cement of the Keene’s cement class is to be prepared the temperature used is higher,e.g.500° C. (= 932° F.), and the whole of the combined water of the gypsum is expelled, the anhydrous sulphate CaSO4being obtained.
To produce plaster of Paris European practice consists in baking the mineral in ovens, and in America in heating it in kettles. Both processes are inferior in economy to calcination in rotatory kilns, a process which may be regarded as the method ofPlaster of Paris; Keene’s cement.the present and the immediate future. Keene’s cement and its congeners are made in fixed kilns so constructed that only the gaseous products of combustion come into contact with the gypsum to be burnt, in order to avoid contamination with the ash of the fuel.The setting of plaster of Paris depends on the fact that when 2CaSO4·H2O is treated with water it dissolves, forming a supersaturated solution of CaSO4·2H2O. The excess held temporarily in solution is then deposited in crystals of CaSO4·2H2O. In the light of this knowledge the mode of setting of plaster of Paris becomes clear. The plaster is mixed with a quantity of water sufficient to make it into a smooth paste; this quantity of water is quite insufficient to dissolve the whole of it, but it dissolves a small part, and gives a supersaturated solution of CaSO4·2H2O. In a few minutes the surplus hydrated calcium sulphate is deposited from the solution, and the water is capable again of dissolving 2CaSO4·H2O, which in turn is fully hydrated and deposited as CaSO4·2H2O. The process goes on until a relatively small quantity of water has by instalments dissolved and hydrated the 2CaSO4·H2O, and has deposited CaSO4·2H2O in felted crystals forming a solid mass well cemented together. The setting is rapid, occupying only a few minutes, and is accompanied by a considerable expansion of the mass. There is reason to suppose that the change described takes place in two stages, the gypsum first forming orthorhombic crystals and then crystallizing in the monosymmetric system. Gypsum thus crystallized is in its normal monosymmetric form, more stable under ordinary conditions than the orthorhombic form. Correlatively in its process of dehydration to form plaster of Paris, monosymmetric gypsum is converted into the orthorhombic form before it begins to be dehydrated.The principles which govern the preparation and setting of the other class of calcium sulphate cements, that is, cements of the Keene class, are not fully understood, but there is a fair amount of knowledge on the subject, both empirical and scientific. The essential difference between the setting of Keene’s cement and that of plaster of Paris is that the former takes place much more slowly, occupying hours instead of minutes, and the considerable heating and expansion which characterize the setting of plaster of Paris are much less marked.It is the practice in Great Britain to burn pure gypsum at a low temperature so as to convert it into the hydrate 2CaSO4·H2O, to soak the lumps in a solution of alum or of aluminium sulphate, and to recalcine them at about 500° C. On grinding they give Keene’s cement. Instead of alum various other salts,e.g.borax, may be used. The quantity of these materials is so small that analyses of Keene’s cement show it to be almost pure anhydrous calcium sulphate, and make it difficult to explain what, if any, influence these minute amounts of alum and the like can exert on the setting of the cement. It seems probable that the effect of the salts is inconsiderable, and that the governing condition is the temperature at which the cement has been burnt. The setting of Keene’s cement takes place by the same sort of process which has been described for the setting of plaster of Paris, the chief differences being that the substance dissolved is anhydrous calcium sulphate and that the operation takes a longer time.All cements having calcium sulphate as their base are suitable only for indoor work because of the solubility of this substance. They form excellent decorative plasters on account of their clean white colour and the sharpness of castings made from them, this latter quantity being due to their expansion when setting.See D.B. Butler,Portland Cement(London, 1905); E.C. Eckel,Cements, Limes and Plasters(New York, 1905); G.R. Redgrave and Charles Spackman,Calcareous Cements(London, 1905); F.H. Lewis, “Manufacture of Hydraulic Cements in the United States,”The Mineral Industry(New York, 1898); W.H. Stanger and Bertram Blount, “Cement Manufacture in Great Britain,”The Mineral Industry, New York, 1897 and 1905;Id. “The Testing of Hydraulic Cements,”Journ. Soc. Chem. Ind.,1894, 13, p. 455;Id., Proc. Inst. Civ. Eng., 1901; B. Blount, “Recent Progress in the Cement Industry,”Journ. Soc. Chem. Ind.,1906, 25, p. 1020; H.L. le Chatelier,Recherrhes experimenlales sur la constitution des mortiers hydrauliques;Desch,Concrete, No. 2, pp. 101-102; Davis,Journ. Soc. Chem. Ind.,1905, 26, p. 727.(B. Bl.)Adhesive Cements.—Mixtures of animal, vegetable and mineral substances are employed in great variety in the arts for making joints, mending broken china and other objects, &c. A strong cement for alabaster and marble, which sets in a day, may be prepared by mixing 12 parts of Portland cement, 8 of fine sand and 1 of infusorial earth, and making them into a thick paste with silicate of soda; the object to be cemented need not be heated. For stone, marble, and earthenware a strong cement, insoluble in water, can be made as follows:—skimmed-milk cheese is boiled in water till of a gluey consistency, washed, kneaded well in cold water, and incorporatedwith quicklime; the composition is warmed for use. A similar cement is a mixture of dried fresh curd with1⁄10th of its weight of quicklime and a little camphor; it is made into a paste with water when employed. A cement for Derbyshire spar and china, &c., is composed of 7 parts of rosin and 1 of wax, with a little plaster of Paris; a small quantity only should be applied to the surfaces to be united, for, as a general rule, the thinner the stratum of a cement, the more powerful its action. Quicklime mixed with white of egg, hardened Canada balsam, and thick copal or mastic varnish are also useful for cementing broken china, which should be warmed before their application. For small articles, shellac dissolved in spirits of wine is a very convenient cement. Cements such as marine glue are solutions of shellac, india-rubber or asphaltum in benzene or naphtha. For use with wood which is exposed to moisture, as in the case of wooden cisterns, a mixture may be made of 4 parts of linseed oil boiled with litharge, and 8 parts of melted glue; other strong cements for the same purpose are prepared by softening gelatine in cold water and dissolving it by heat in linseed oil, or by mixing glue with one-fourth of its weight of turpentine, or with a little bichromate of potash.Mahogany cement, for filling up cracks in wood, consists of 4 parts of beeswax, 1 of Indian red and yellow-ochre to give colour.Cutler’s cement, used for fixing knife-blades in their hafts, is made of equal parts of brick-dust and melted rosin, or of 4 parts of rosin with 1 each of beeswax and brick-dust. For covering bottle-corks a mixture of pitch, brick-dust and rosin is employed. A cheap cement, sometimes employed to fix iron rails in stone-work, is melted brimstone, or brimstone and brick-dust. For pipe-joints, a mixture of iron turnings, sulphur and sal ammoniac, moistened with water, is employed.Japanese cement, for uniting surfaces of paper, is made by mixing rice-flour with water and boiling it.Jewellers’orArmenian cementconsists of isinglass with mastic and gum ammoniac dissolved in spirit. Gold and silver chasers keep their work firm by means of a cement of pitch and rosin, a little tallow, and brick-dust to thicken.Temporary cementfor lathe-work, such as the polishing and grinding of jewelry and optical glasses, is compounded thus:—rosin, 4 oz.; whitening previously made red-hot, 4 oz.; wax, ¼ oz.
To produce plaster of Paris European practice consists in baking the mineral in ovens, and in America in heating it in kettles. Both processes are inferior in economy to calcination in rotatory kilns, a process which may be regarded as the method ofPlaster of Paris; Keene’s cement.the present and the immediate future. Keene’s cement and its congeners are made in fixed kilns so constructed that only the gaseous products of combustion come into contact with the gypsum to be burnt, in order to avoid contamination with the ash of the fuel.
The setting of plaster of Paris depends on the fact that when 2CaSO4·H2O is treated with water it dissolves, forming a supersaturated solution of CaSO4·2H2O. The excess held temporarily in solution is then deposited in crystals of CaSO4·2H2O. In the light of this knowledge the mode of setting of plaster of Paris becomes clear. The plaster is mixed with a quantity of water sufficient to make it into a smooth paste; this quantity of water is quite insufficient to dissolve the whole of it, but it dissolves a small part, and gives a supersaturated solution of CaSO4·2H2O. In a few minutes the surplus hydrated calcium sulphate is deposited from the solution, and the water is capable again of dissolving 2CaSO4·H2O, which in turn is fully hydrated and deposited as CaSO4·2H2O. The process goes on until a relatively small quantity of water has by instalments dissolved and hydrated the 2CaSO4·H2O, and has deposited CaSO4·2H2O in felted crystals forming a solid mass well cemented together. The setting is rapid, occupying only a few minutes, and is accompanied by a considerable expansion of the mass. There is reason to suppose that the change described takes place in two stages, the gypsum first forming orthorhombic crystals and then crystallizing in the monosymmetric system. Gypsum thus crystallized is in its normal monosymmetric form, more stable under ordinary conditions than the orthorhombic form. Correlatively in its process of dehydration to form plaster of Paris, monosymmetric gypsum is converted into the orthorhombic form before it begins to be dehydrated.
The principles which govern the preparation and setting of the other class of calcium sulphate cements, that is, cements of the Keene class, are not fully understood, but there is a fair amount of knowledge on the subject, both empirical and scientific. The essential difference between the setting of Keene’s cement and that of plaster of Paris is that the former takes place much more slowly, occupying hours instead of minutes, and the considerable heating and expansion which characterize the setting of plaster of Paris are much less marked.
It is the practice in Great Britain to burn pure gypsum at a low temperature so as to convert it into the hydrate 2CaSO4·H2O, to soak the lumps in a solution of alum or of aluminium sulphate, and to recalcine them at about 500° C. On grinding they give Keene’s cement. Instead of alum various other salts,e.g.borax, may be used. The quantity of these materials is so small that analyses of Keene’s cement show it to be almost pure anhydrous calcium sulphate, and make it difficult to explain what, if any, influence these minute amounts of alum and the like can exert on the setting of the cement. It seems probable that the effect of the salts is inconsiderable, and that the governing condition is the temperature at which the cement has been burnt. The setting of Keene’s cement takes place by the same sort of process which has been described for the setting of plaster of Paris, the chief differences being that the substance dissolved is anhydrous calcium sulphate and that the operation takes a longer time.
All cements having calcium sulphate as their base are suitable only for indoor work because of the solubility of this substance. They form excellent decorative plasters on account of their clean white colour and the sharpness of castings made from them, this latter quantity being due to their expansion when setting.
See D.B. Butler,Portland Cement(London, 1905); E.C. Eckel,Cements, Limes and Plasters(New York, 1905); G.R. Redgrave and Charles Spackman,Calcareous Cements(London, 1905); F.H. Lewis, “Manufacture of Hydraulic Cements in the United States,”The Mineral Industry(New York, 1898); W.H. Stanger and Bertram Blount, “Cement Manufacture in Great Britain,”The Mineral Industry, New York, 1897 and 1905;Id. “The Testing of Hydraulic Cements,”Journ. Soc. Chem. Ind.,1894, 13, p. 455;Id., Proc. Inst. Civ. Eng., 1901; B. Blount, “Recent Progress in the Cement Industry,”Journ. Soc. Chem. Ind.,1906, 25, p. 1020; H.L. le Chatelier,Recherrhes experimenlales sur la constitution des mortiers hydrauliques;Desch,Concrete, No. 2, pp. 101-102; Davis,Journ. Soc. Chem. Ind.,1905, 26, p. 727.
(B. Bl.)
Adhesive Cements.—Mixtures of animal, vegetable and mineral substances are employed in great variety in the arts for making joints, mending broken china and other objects, &c. A strong cement for alabaster and marble, which sets in a day, may be prepared by mixing 12 parts of Portland cement, 8 of fine sand and 1 of infusorial earth, and making them into a thick paste with silicate of soda; the object to be cemented need not be heated. For stone, marble, and earthenware a strong cement, insoluble in water, can be made as follows:—skimmed-milk cheese is boiled in water till of a gluey consistency, washed, kneaded well in cold water, and incorporatedwith quicklime; the composition is warmed for use. A similar cement is a mixture of dried fresh curd with1⁄10th of its weight of quicklime and a little camphor; it is made into a paste with water when employed. A cement for Derbyshire spar and china, &c., is composed of 7 parts of rosin and 1 of wax, with a little plaster of Paris; a small quantity only should be applied to the surfaces to be united, for, as a general rule, the thinner the stratum of a cement, the more powerful its action. Quicklime mixed with white of egg, hardened Canada balsam, and thick copal or mastic varnish are also useful for cementing broken china, which should be warmed before their application. For small articles, shellac dissolved in spirits of wine is a very convenient cement. Cements such as marine glue are solutions of shellac, india-rubber or asphaltum in benzene or naphtha. For use with wood which is exposed to moisture, as in the case of wooden cisterns, a mixture may be made of 4 parts of linseed oil boiled with litharge, and 8 parts of melted glue; other strong cements for the same purpose are prepared by softening gelatine in cold water and dissolving it by heat in linseed oil, or by mixing glue with one-fourth of its weight of turpentine, or with a little bichromate of potash.Mahogany cement, for filling up cracks in wood, consists of 4 parts of beeswax, 1 of Indian red and yellow-ochre to give colour.Cutler’s cement, used for fixing knife-blades in their hafts, is made of equal parts of brick-dust and melted rosin, or of 4 parts of rosin with 1 each of beeswax and brick-dust. For covering bottle-corks a mixture of pitch, brick-dust and rosin is employed. A cheap cement, sometimes employed to fix iron rails in stone-work, is melted brimstone, or brimstone and brick-dust. For pipe-joints, a mixture of iron turnings, sulphur and sal ammoniac, moistened with water, is employed.Japanese cement, for uniting surfaces of paper, is made by mixing rice-flour with water and boiling it.Jewellers’orArmenian cementconsists of isinglass with mastic and gum ammoniac dissolved in spirit. Gold and silver chasers keep their work firm by means of a cement of pitch and rosin, a little tallow, and brick-dust to thicken.Temporary cementfor lathe-work, such as the polishing and grinding of jewelry and optical glasses, is compounded thus:—rosin, 4 oz.; whitening previously made red-hot, 4 oz.; wax, ¼ oz.
CEMETERY(Gr.κοιμητήριον, fromκοιμᾶν, to sleep), literally a sleeping-place, the name applied by the early Christians to the places set apart for the burial of their dead. These were generally extra-mural and unconnected with churches, the practice of interment in churches or churchyards being unknown in the first centuries of the Christian era. The term cemetery has, therefore, been appropriately applied in modern times to the burial-grounds, generally extra-mural, which have been substituted for the overcrowded churchyards (q.v.) of populous parishes both urban and rural.
From 1840 to 1855, attention was repeatedly called to the condition of the London churchyards by correspondence in the press and by the reports of parliamentary committees, the first of which, that of Mr Chadwick, appeared in 1843. The vaults under the pavement of the churches, and the small spaces of open ground surrounding them, were crammed with coffins. In many of the buildings the air was so tainted with the products of corruption as to be a direct and palpable source of disease and death to those who frequented them. In the churchyards coffins were placed tier above tier in the graves until they were within a few feet (or sometimes even a few inches) of the surface, and the level of the ground was often raised to that of the lower windows of the church. To make room for fresh interments the sextons had recourse to the surreptitious removal of bones and partially-decayed remains, and in some cases the contents of the graves were systematically transferred to pits adjacent to the site, the grave-diggers appropriating the coffin-plates, handles and nails to be sold as waste metal. The neighbourhood of the churchyards was always unhealthy, the air being vitiated by the gaseous emanations from the graves, and the water, wherever it was obtained from wells, containing organic matter, the source of which could not be mistaken. In all the large towns the evil prevailed in a greater or less degree, but in London, on account of the immense population and the consequent mortality, it forced itself more readily upon public attention, and after more than one partial measure of relief had been passed the churchyards were, with a few exceptions, finally closed by the act of 1855, and the cemeteries which now occupy a large extent of ground to the north, south, east and west became henceforth the burial-places of the metropolis. Several of them had been already established by private enterprise before the passing of the Burial Act of 1855 (Kensal Green cemetery dates from 1832), but that enactment forms the epoch from which the general development of cemeteries in Great Britain and Ireland began. Burial within the limits of cities and towns is now almost everywhere abolished, and where it is still in use it is surrounded by such safeguards as make it practically innocuous. This tendency has been conspicuous both in the United Kingdom and the United States. The increasing practice of cremation (q.v.) has assisted in the movement for disposing of the dead in more sanitary conditions; and the proposals of Sir Seymour Haden and others for burying the dead in more open coffins, and abandoning the old system of family graves, have had considerable effect. The tendency has therefore been, while improving the sanitary aspects of the disposal of the dead, to make the cemeteries themselves as fit as possible for this purpose, and beautiful in arrangement and decoration.
The chief cemeteries of London are Kensal Green cemetery on the Harrow Road; Highgate cemetery on the slope of Highgate Hill; the cemetery at Abney Park (once the residence of Dr Watts); the Norwood and Nunhead cemeteries to the south of London; the West London cemetery at Brompton; the cemeteries at Ilford and Leytonstone in Essex; the Victoria cemetery and the Tower Hamlets cemetery in East London; and at a greater distance, accessible by railway, the great cemetery at Brookwood near Woking in Surrey, and the cemetery at New Southgate. The general plan of all these cemeteries is the same, a park with broad paths either laid out in curved lines as at Kensal Green and Highgate, or crossing each other at right angles as in the case of the West London cemetery. The ground on each side of these paths is marked off into grave spaces, and trees and shrubs are planted in the intervals between them. The buildings consist of a curator’s residence and one or more chapels, and usually there is also a range of family graves with imposing tombs, massive structures containing in their corridors recesses for the reception of coffins, generally closed only by an iron grating. The provincial cemeteries in the main features of their arrangements resemble those of the metropolis. One of the most remarkable is St James’s cemetery at Liverpool, which occupies a deserted quarry. The face of the eastern side of the quarry is traversed by ascending gradients off which open catacombs formed in the living rock,—a soft sandstone; the ground below is planted with trees, amongst which stand hundreds of gravestones. The main approach on the north side is through a tunnel, above which, on a projecting rock, stands the cemetery chapel, built in the form of a small Doric temple with tetrastyle porticos.
Many of the cities of America possess very fine cemeteries. One of the largest, and also the oldest, is that of Mount Auburn near Boston. Others of importance are the Laurel Hill cemetery (1836) at Philadelphia; the Greenwood cemetery (1838) at Brooklyn (New York); the Lake View cemetery at Cleveland, Ohio; while the cemeteries at New Orleans (q.v.) are famous for their beauty.
The chief cemetery of Paris is that of Père la Chaise, the prototype of the garden cemeteries of western Europe. It takes its name from the celebrated confessor of Louis XIV., to whom as rector of the Jesuits of Paris it once belonged. It was laid out as a cemetery in 1804. It has an area of about 200 acres, and contains about 20,000 monuments, including those of all the great men of France of the 19th century—marshals, generals, ministers, poets, painters, men of science and letters, actors and musicians. Twice the cemetery and the adjacent heights have been the scene of a desperate struggle; in 1814 they were stormed by a Russian column during the attack on Paris by the allies, and in 1871 the Communists made their last stand among the tombs of Père la Chaise; 900 of them fell in the defence of the cemetery or were shot there after its capture, and 200 of them were buried in quicklime in one huge grave and 700 in another. There are other cemeteries at Mont Parnasse and Montmartre, besides the minor burying-grounds at Auteuil, Batignolles, Passy, La Villette, &c. In consequence of all these cemeteries being more or less crowded, a great cemetery was laid out in 1874 on the plateau of Méry sur Oise, 16 m. to the north of Paris, with whichit is connected by a railway line. It includes within its circuit fully 2 sq. m. of ground. The French cemetery system differs in many respects from the English. Every city and town is required by law to provide a burial-ground beyond its barriers, properly laid out and planted, and situated if possible on a rising ground. Each interment must take place in a separate grave. This, however, does not apply to Paris, where the dead are buried, forty or fifty at a time, in thefosses communes, the poor being interred gratuitously, and a charge of 20 francs being made in all other cases. Thefosseis filled and left undisturbed for five years, then all crosses and other memorials are removed, the level of the ground is raised 4 or 5 ft. by fresh earth, and interments begin again. For a fee of 50 francs aconcession temporairefor ten years can be obtained, but where it is desired to erect a permanent monument the ground must be bought by the executors of the deceased. In Paris the undertakers’ trade is the monopoly of a company, theSociété des pompes funèbres, which in return for its privileges is required to give a free burial to the poor.
TheLeichenhäuser, or dead-houses, of Frankfort and Munich form a remarkable feature of the cemeteries of these cities. The object of their founders was twofold—(1) to obviate even the remotest danger of premature interment, and (2) to offer a respectable place for the reception of the dead, in order to remove the corpse from the confined dwellings of the survivors. At Frankfort the dead-house occupies one of the wings of the propylaeum, which forms the main entrance to the cemetery. It consists of the warder’s room, where an attendant is always on duty, on each side of which there are five rooms, well ventilated, kept at an even temperature, and each provided with a bier on which a corpse can be laid. On one of the fingers is placed a ring connected by a light cord with a bell which hangs outside in the warder’s room. The use of the dead-house is voluntary. The bodies deposited there are inspected at regular intervals by a medical officer, and the warder is always on the watch for the ringing of the warning bell. One revival, that of a child, has been known to take place at Frankfort. The Leichenhaus of Munich is situated in the southern cemetery outside the Sendling Gate. At one end of the cemetery there is a semicircular building with an open colonnade in front and a projection behind, which contains three large rooms for the reception of the dead. At both Frankfort and Munich great care is taken that the attendants receive the dead confided to them with respect, and no interment is permitted until the first signs of decomposition appear; the relatives then assemble in one of the halls adjoining the Leichenhaus, and the funeral takes place. In any case there is, with ordinary care, little fear of premature interment, but in another way such places of deposit for the dead are of great use in large towns, as they prevent the evil effects which result from the prolonged retention of the dead among the living. Mortuaries for this purpose have also been established in many places in England.
In Italy theCampo Santo(Holy Field) is best illustrated by the famous one at Pisa, from which the name has been given to other Italian burying-grounds. Of the cemeteries still in use in southern Europe the catacombs (q.v.) of Sicily are the most curious. There is one of these under the old Capuchin monastery of Ziza near Palermo, where in four large airy subterranean corridors 2000 corpses are ranged in niches in the wall, many of them shrunk up into the most grotesque attitudes, or hanging with pendent limbs and head from their places. As a preparation for the niche, the body is desiccated in a kind of oven, and then dressed as in life and raised into its place in the wall. At the end of the principal corridor at Ziza there is an altar strangely ornamented with a kind of mosaic of human skulls and bones.
Cemeteries have been in use among many Eastern nations from time immemorial. In China, the high grounds near Canton and Macao are crowded with tombs, many of them being in the form of small tumuli, with a low encircling wall, forcibly recalling the ringed barrows of western Europe. But the most picturesque cemeteries in the world are those of the Turks. From them it was, perhaps, that the first idea of the modern cemetery, with its ornamental plantations, was derived. Around Constantinople the cemeteries form vast tracts of cypress woods under whose branches stand thousands of tombstones. A grave is never reopened; a new resting-place is formed for every one, and so the dead now occupy a wider territory than that which is covered by the homes of the living. The Turks believe that till the body is buried the soul is in a state of discomfort, and the funeral, therefore, takes place as soon as possible after death. No coffin is used, the body is laid in the grave, a few boards are arranged round it, and then the earth is shovelled in, care being taken to leave a small opening extending from the head of the corpse to the surface of the ground, an opening not unfrequently enlarged by dogs and other beasts which plunder the grave. A tombstone of white marble is then erected, surmounted by a carved turban in the case of a man, and ornamented by a palm branch in low relief if the grave is that of a woman. The turban by its varying form indicates not only the rank of the sleeper below but also the period of his death, for the fashion of the Turkish head-dress is always changing. A cypress is usually planted beside the grave, its odour being supposed to neutralize any noxious exhalations from the ground, and thus every cemetery is a forest, where by day hundreds of turtle doves are on the wing or perching on the trees, and where bats and owls swarm undisturbed at night. Especially for the Turkish women the cemeteries are a favourite resort, and some of them are always to be seen praying beside the narrow openings that lead down into a parent’s, a husband’s, or a brother’s grave. Some of the other cemeteries of Constantinople contrast rather unfavourably with the simple dignity of those which belong to the Turks. That of the Armenians abounds with bas-reliefs which show the manner of the death of whoever is buried below, and on these singular tombstones there are frequent representations of men being decapitated or hanging on the gallows.
See also the articlesBurial and Burial Acts;Cremation;Funeral Rites;Churchyard.
See also the articlesBurial and Burial Acts;Cremation;Funeral Rites;Churchyard.
CENCI, BEATRICE(1577-1599), a Roman woman, famous for her tragic story; poetic fancy has woven a halo of romance about her, which modern historic research has to a large extent destroyed. Born at Rome, she was the daughter of Francesco Cenci (1549-1598), the bastard son of a priest, and a man of great wealth but dissolute habits and violent temper. He seems to have been guilty of various offences and to have got off with short terms of imprisonment by bribery; but the monstrous cruelty which popular tradition has attributed to him is purely legendary. His first wife, Ersilia Santa Croce, bore him twelve children, and nine years after her death he married Lucrezia Petroni, a widow with three daughters, by whom he had no offspring. He was very quarrelsome and lived on the worst possible terms with his children, who, however, were all of them more or less disreputable. He kept various mistresses and was even prosecuted for unnatural vice, but his sons were equally dissolute. His harsh treatment of his daughter Beatrice was probably due to his discovery that she had had an illegitimate child as the result of an intrigue with one of his stewards (A. Bertolotti, in hisFrancesco Cenci, publishes Beatrice’s will in which she provides for this child), but there is no evidence that he tried to commit incest with her, as has been alleged. The eldest son Giacomo was a riotous, dishonest young scoundrel, who cheated his own father and even attempted to murder him (1595). Two other sons, Rocco and Cristoforo, both of them notorious rakes, were killed in brawls. Finally Francesco’s wife Lucrezia and his children Giacomo, Bernardo and Beatrice, assisted by a certain Monsignor Guerra, plotted to murder him. Two bravos were hired (one of them named Olimpio, according to Bertolotti, was probably Beatrice’s lover), and Francesco was assassinated while asleep in his castle of Petrella in the kingdom of Naples (1598). Giacomo afterwards had one of the bravos murdered, but the other was arrested by the Neapolitan authorities and confessed everything. Information having been communicated to Rome, the whole of the Cenci family were arrested early in 1599; but the story of the hardships they underwent in prison is greatly exaggerated. Guerra escaped;Lucrezia, Giacomo and Bernardo confessed the crime; and Beatrice, who at first denied everything, even under torture, also ended by confessing. Great efforts were made to obtain mercy for the accused, but the crime was considered too heinous, and the pope (Clement VIII.) refused to grant a pardon; on the 11th of September 1599, Beatrice and Lucrezia were beheaded, and Giacomo, after having been tortured with red-hot pincers, was killed with a mace, drawn and quartered. Bernardo’s penalty, on account of his youth, was commuted to perpetual imprisonment, and after a year’s confinement he was pardoned. The property of the family was confiscated.
The romantic character of the history of this family has been the subject of poems, dramas and novels. Shelley’s tragedy is well known as a magnificent piece of writing, although the author adopts a purely fictitious version of the story. Nor is F.D. Guerrazzi’s novel,Beatrice Cenci(Milan, 1872), more trustworthy. The first attempt to deal with the subject on documentary evidence is A. Bertolotti’sFrancesco Cenci e la sua famiglia(2nd ed., Florence, 1879), containing a number of interesting documents which place the events in their true light; cf. Labruzzi’s article in theNuova Antologia, 1879, vol. xiv., and another in theEdinburgh Review, January 1879.
The romantic character of the history of this family has been the subject of poems, dramas and novels. Shelley’s tragedy is well known as a magnificent piece of writing, although the author adopts a purely fictitious version of the story. Nor is F.D. Guerrazzi’s novel,Beatrice Cenci(Milan, 1872), more trustworthy. The first attempt to deal with the subject on documentary evidence is A. Bertolotti’sFrancesco Cenci e la sua famiglia(2nd ed., Florence, 1879), containing a number of interesting documents which place the events in their true light; cf. Labruzzi’s article in theNuova Antologia, 1879, vol. xiv., and another in theEdinburgh Review, January 1879.
CENOBITES(from Gr.κοινός, common, andβίος, life), monks who lived together in a convent or community under a rule and a superior,—in contrast to hermits or anchorets who live in isolation. The Basilians (q.v.) in the East and the Benedictines (q.v.) in the West are the chief cenobitical orders (seeMonasticism).
CENOMANI,a branch of the Aulerci in Gallia Celtica, whose territory corresponded generally to Maine in the modern department of Sarthe. Their chief town was Vindinum or Suindinum (corrupted into Subdinnum), afterwards Civitas Cenomanorum (whence Le Mans), the original name of the town, as usual in the case of Gallic cities, being replaced by that of the people. According to Caesar (Bell. Gall.vii. 75. 3), they assisted Vercingetorix in the great rising (52b.c.) with a force of 5000 men. Under Augustus they formed acivitas stipendiariaof Gallia Lugdunensis, and in the 4th century part of Gallia Lugdunensis iii. About 400b.c., under the leadership of Elitovius (Livy v. 35), a large number of the Cenomani crossed into Italy, drove the Etruscans southwards, and occupied their territory. The statement of Cato (in Pliny,Nat. Hist.iii. 130), that some of them settled near Massilia in the territory of the Volcae, may indicate the route taken by them. The limits of their territory are not clearly defined, but were probably the Athesis (Adige or Etsch) on the east, the Ollius (Oglio, or perhaps the Addua) on the west, and the Padus on the south. Livy gives their chief towns as Brixia (Brescia) and Verona; Pliny, Brixia and Cremona. The Cenomani nearly always appear in history as loyal friends and allies of the Romans, whom they assisted in the Gallic war (225b.c.), when the Boii and Insubres took up arms against Rome, and during the war against Hannibal. They certainly joined in the revolt of the Gauls under Hamilcar (200), but after they had been defeated by the consul Gaius Cornelius (197) they finally submitted. In 49, with the rest of Gallia Transpadana, they acquired the rights of citizenship.
The orthography and the quantity of the penultimate vowel of Cenomani have given rise to discussion. According to Arbois de Jubainville, the Cenomăni of Italy are not identical with the Cenomāni (or Cenomanni) of Gaul. In the case of the latter, the survival of the syllable “man” in Le Mans is due to the stress laid on the vowel; had the vowel been short and unaccented, it would have disappeared. In Italy, Cenomani is the name of a people; in Gaul, merely a surname of the Aulerci.
See A. Voisin,Les Cénomans anciens et modernes(Le Mans, 1862); A. Desjardins,Géographic historique de la Gaule romaine,ii. (1876-1893); Arbois de Jubainville,Les Premiers Habitants de l’Europe(1889-1894); article and authorities inLa Grande Encyclopédie; C. Hulsen in Pauly-Wissowa’sRealencyclopadie, iii. pt. 2 (1899); full ancient authorities in A. Holder,Alt-celtischer Sprachschatz, i. (1896).
See A. Voisin,Les Cénomans anciens et modernes(Le Mans, 1862); A. Desjardins,Géographic historique de la Gaule romaine,ii. (1876-1893); Arbois de Jubainville,Les Premiers Habitants de l’Europe(1889-1894); article and authorities inLa Grande Encyclopédie; C. Hulsen in Pauly-Wissowa’sRealencyclopadie, iii. pt. 2 (1899); full ancient authorities in A. Holder,Alt-celtischer Sprachschatz, i. (1896).
CENOTAPH(Gr.κενός, empty,τάφος, tomb), a monument or tablet to the memory of a person whose body is buried elsewhere. The custom arose from the erection of monuments to those whose bodies could not be recovered, as in the case of drowning.
CENSOR(from Lat.censere, assess, estimate; in Gr.τιμητής). I.In ancient Rome, the title of the two Roman officials who presided over the census, the registration of individual citizens for the purpose of determining the duties which they owed to the community. In the etymology of the word lurks the idea of the arbitrary assignment of burdens or duties. Varro definescensusasarbitrium, and derives the namecensoresfrom the position of these magistrates asarbitri populi(Varro,de Ling. Lat.v. 81;ap.Non. p. 519). This original idea of “discretionary power” was never entirely lost; although ultimately it came to be more intimately associated with the appreciation of morals than with the assignment of burdens. From the point of view of its moral significance the censorship was the Roman manifestation of that state control of conduct which was a not unusual feature of ancient societies. It is true that Rome possessed sumptuary laws, and laws dealing with moral offences, which it was the duty of other magistrates to enforce; but the organization for the control of conduct was mainly exhibited in the censorship, and, as thus exhibited, was at once simple and comprehensive.
The censorship was believed to have been instituted in 443b.c.to relieve the consuls of the duties of registration. Since the periods of registration were quinquennial, it was not a continuous office; but its tenure does not seem to have been fixed until 434b.c., when alex Aemiliaprovided that the censors should hold office for eighteen months. This magistracy was at first confined to patricians; a plebeian censor is first mentioned in 351b.c.Alex Publiliaof 339b.c.is said to have enacted that one censor must be a plebeian. Two plebeian censors were for the first time elected in 131b.c.The election always took place in the Comitia Centuriata (seeComitia). The censorship, although lacking the powers implied in the imperium and the right of summoning the senate and the people, was not only one of the higher magistracies, but was regarded as the crown of a political career. It was an irresponsible office; and the only limitations on its powers were created by the restriction of tenure to a year and a half, the fact that re-election was forbidden, and the restraint imposed on each censor by the fact that no act of his was valid without the assent of his colleague.
The original functions of the censors were (1) the registration of citizens in the state-divisions, such as tribes and centuries; (2) the taxation of such citizens based on an estimate of their property; (3) the right of exclusion from public functions on moral grounds, known as theregimen morum; (4) the solemn act of purification (lustrum) which closed the census. Two other functions were subsequently added:—(5) the selection of the senate (lectio senatus, seeSenate), and (6) certain financial duties such as the leasing of the contracts for tax-collecting and for the repair of public buildings. The first four of these functions were those of the census, which was a detailed examination of the citizen body as represented by heads of families (patres familiarum) in the Campus Martius. The equites were a select portion of this citizen body; but the review of these knights took place, not in the Campus, but in the Forum (seeEquites). It was in connexion with this review of the ordinary citizens and the knights, as well as with the choice of senators, that the censors published their edicts stating the moral rules which they intended to enforce. The offences which they punished were sometimes concerned with family life and private relations, sometimes with breaches of political duty. Certain professions, such as that of an actor or gladiator, also invoked their stigma, and at times the disqualifications they pronounced were the consequence of a previous judicial condemnation.Infamiawas the general name given to the disabilities pronounced by the censor. These varied in degree from the deprivation of a senator of his seat, or a knight’s loss of his horse, to exclusion from the tribes or centuries, an exclusion which entailed the loss of voting power. All the disabilities pronounced by one pair of censors might be removed by their successors.
The censorship, although its control over the senate came tobe weakened (seeSenate), lasted as long as the republic; and it was only suspended, not abolished, during the principate. Although the princeps exercised censorial functions, he was seldom censor. Yet the office itself was held by Claudius I. and Vespasian. Domitian assumed the title of life censor (censor perpetuus), but the precedent was not followed. A fruitless attempt to galvanize the republican office into new life was made ina.d.251, during the reign of the emperor Decius.
Authorities.—Mommsen,Romisches Staatsrecht, ii. 331 foll. (3rd ed., Leipzig, 1887); Daremberg-Saglio,Dictionnaire des antiquités grecques et romaines, i. 990 foll. (1875, &c.); Lange,Romische Alterthumer, i. 572 foll. (Berlin, 1856, &c.); de Boor,Fasti Censorii(Berlin, 1873); Gerlach,Die romische Censur in ihrem Verhaltnisse zur Verfassung(Basel, 1842); Nitzsch, “Über die Census” inNeues Jahrbuch f. Phil.lxxiii. 730 (Leipzig, 1856); Zumpt, “Die Lustra der Römer” inRhein. Museum, xxv. 465, xxvi. i.
Authorities.—Mommsen,Romisches Staatsrecht, ii. 331 foll. (3rd ed., Leipzig, 1887); Daremberg-Saglio,Dictionnaire des antiquités grecques et romaines, i. 990 foll. (1875, &c.); Lange,Romische Alterthumer, i. 572 foll. (Berlin, 1856, &c.); de Boor,Fasti Censorii(Berlin, 1873); Gerlach,Die romische Censur in ihrem Verhaltnisse zur Verfassung(Basel, 1842); Nitzsch, “Über die Census” inNeues Jahrbuch f. Phil.lxxiii. 730 (Leipzig, 1856); Zumpt, “Die Lustra der Römer” inRhein. Museum, xxv. 465, xxvi. i.