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with a rooted stem, giving off branches, through the orifices of which the polypes emerge, as in Sertularia.
Sertularia. Part of a branch magnified, to show the open cells from which the polypes emerge.
In other cases the tubes are collected Gorgonia pustulosa, showing the pustular gelat- into bundles, like reeds bound together, inous investment, and the flexible horny stems, and open at one end, through which the
polypes protrude, and into which they can In other instances, it is composed of retire. Such is the case in the Tubipore, flexible horny matter, with calcareous
a group of which many fossil species are knots at regular intervals, as in Isis Hip- known. puris.
Tubipora. Polypes protruding from some of the tubes.
Distinct from both the cortical and tubular polypes are the Alcyonida, (Al
Isis Hippuris. Part denuded of the living gelatine, to show the structure of the axis or polypary.
But again, suppose the common gelatine, instead of surrounding a stem, or axis, should form for itself an investing tube, in which, as in a sheath to lodge, with apertures, through which the polypes can protrude themselves, and expand their tentacles for food; we have here a compound tubular zoophyte.
Great is the variety of form which these tubular zoophytes present: some
Cydonium. assume the appearance of little trees, cyonium, Cydonium, etc.) In these a
tough, sub-cartilaginous body, often with are termed sea-pens, from their resemcalcareous spicula interspersed through blance to a quill feather, a double set of it, and containing numerous canals, is branches, on the same place, occupying studded with polypes, like hydras. These both sides of a shaft. Each branch is are all seated in little cells on the sur- furnished with a row of polypes, resemface, from which they can protrude and bling the barbules along the filaments, or expand their tentacles.
barbs, composing the vane of a quill. Cuvier regards the Pennatulæ, or sea- It has been considered by many, that
the pennatulæ are capable of rowing themselves along; but this does not appear to be the case. Numbers are found floating on the ocean, carried along with the stream. Many are phosphorescent.
The Actiniæ, or sea anemonies, certainly form a distinct section. Most of these are single, as the common actinia of our rocky shores, each polype being one animal. But in the genus Zoanthus,
numbers rise from a creeping root-like pens, as forming a distinct section, and base, attached to the surface of the rock. terms them swimming, or detached po- The organization of the actiniæ, or lypes.
fleshy polypes, advances far higher in The Pennatulæ have, however, a cal- | the scale than does that of the other careous axis, though not fixed. They | groups.-M.
BRICK MAKING.-No. I.
burned brick was used instead of stone in We are indebted to a volume lately these constructions; and that slime, which published, containing a series of papers is generally understood to be bitumen, by Dr. Aikin, for the following interest- was employed instead of mortar. Coning statements.
siderable progress appears to have been The manufacture of bricks goes up to made in building both the city and the the very earliest time of historical record. tower before what is called the confusion In the book of Genesis, Nimrod is stated of tongues took place, in consequence of to have been the first sovereign, and to which the work was abandoned. Nearly have reigned in the land of Shinar, one on the same site was afterwards founded of the towns of which was Babel. The the celebrated city of Babel, or Babylon; first building after the flood, of which which is described by Herodotus, the oldany mention is made, was the Tower of est Greek historian, as surrounded by a Babel. It is expressly stated that well- deep and wide trench, the earth from which was formed into bricks. These bricks of the wall. At the top of the mound is were then burned in furnaces or kilns, and a solid pile, thirty-seven feet high, of were employed part in lining the trench, burned bricks, with inscriptions, and set in and the remainder in building the walls ; lime mortar. the cement used was hot bitumen, and From the proportions of the three stobetween every thirty courses of bricks ries that now remain, it seems probable was a layer of mats, composed of reeds. that the mound or pyramid consisted, or The ruins of Babylon are still visible, in perhaps was intended to consist, of five the form of hillocks, or high mounds, stories; the three lower of which were and have been visited of late years, and solid, and the two upper would probably described by several travellers. The late have contained chambers. Whether this Mr. Rich appears to have examined these pile is the unfinished tower of Babel or remains with great care; and from his not, is at present only matter of conjecmemoir, the following particulars, as far ture: its local situation with regard to as relates to our immediate subject, are the other mounds is rather in favour of derived. Most of the mounds appear to the hypothesis ; and the specimens of have a certain degree of connexion with bricks now exhibited, which were obone another ; but the largest of the tained from this very mound, will be mounds, the Birs Nemrood, together with regarded with no small interest; they another adjacent, called Akerkouf, is so form part of the collection of the East far distant from the others as to render it India Company. doubtful if it could have been included The manufacture of bricks was also within the extent of the Babylon described known to the ancient Egyptians. Every by Herodotus.
body is aware that one of the modes of The connected mounds present walls oppression practised by this people toand passages, or galleries, formed of well-wards the Israelites, was the unreasonburned brick, laid in lime mortar of ex- able requisition from them of a certain treme toughness; but in one of them, number of bricks: it is not mentioned called the tower of Belus, large solid that these bricks were burned ; indeed, masses, or fillings up between the wall, the circumstance of their being mixed are observed of unburned bricks. These with chopped straw, like the unbaked latter are more rudely shaped than the bricks found in Babylon, renders it proburned bricks, being rather clods of earth, bable that they were only sun-dried. composed of a kind of clay mortar, in- Herodotus also records of Asychis
, one termixed with chopped straw to prevent of the kings of Egypt, that he built a it from falling to pieces : these unburned pyramid of bricks made of the mud or bricks are laid in very thick cement of silt dredged up from the bottom of the clay, with layers of reeds above the river. This is perhaps the same as that courses of brick.
called by Pococke the pyramid of MenshehThe Birs Nemrood is at presenta mound dushour, and by Norden the pyramid of seven hundred and sixty-two yards in cir- Meidun: it was visited by both these cumference, and one hundred and ninety- travellers, and is described by them as eight feet high; it consists of three steps, consisting of five degrees, each fifty feet or receding stories : the interior of the high, and the base one hundred and mass appears to consist of layers of un- fifty-seven by two hundred and ten feet ; burned bricks set in clay, sometimes with it is formed of unburned bricks, comout layers of reeds, sometimes with them, posed of a mixture of clay and chopped laid between every five or six courses of straw. Such unburned bricks, Pococke bricks. This mass is in some parts faced adds, are still used in Egypt. It is pro(and probably when perfect was com- bable, that in the time of Pliny the elder, pletely so) with layers of burned bricks set who lived in the reign of Vespasian, in bitumen. These bricks are about thir- unburned bricks were in use elsewhere on teen inches square by three inches thick, the north coast of Africa ; for that auand have indented inscriptions, apparently thor mentions, that at Utica no bricks made by a stamp, in a character at pre- were allowed to be used that had not sent wholly unknown, the elements of been dried five years in the sun; a reguwhich appear to have been representa- lation which apparently would be absurd tions of arrows or broad-headed nails, if applied to baked ones. But sun-dried variously combined together. The bricks bricks may rather be considered as are laid with the written face downward, kind of artificial stone than earthenware; so that they were not visible on the front and, from the circumstance of chopped
straw being mixed with them, the clay / are made in India by tempering clay, was probably much more sandy and less then spreading it on a mat, and making tenacious, than that required for burned it of an uniform thickness, and when it bricks, and approached nearly to the loam is half dry, dividing it into bricks: these employed at present in building walls bricks are then baked in clamps. But it by ramming, or en pisé; a mode of con- has sometimes happened, in consequence struction which also was well known to of those hostile incursions by which India the ancients, Hannibal having construct has been so often desolated, that when ed several towers on the coast of Spain a district has been laid waste, and not of this material.
re-occupied for several years, clamps Certain other celebrated buildings of of bricks, ready for burning, have been high antiquity were also formed of brick : abandoned. On the return of the insuch were the palaces of Cræsus at Sar- habitants, such clamps have been found dis, of Mausolus at Halicarnassus, and of so much injured by the rains, and other Attalus at Tralles; all of which were still causes, as not to be worth the expense of remaining in the reign of Trajan. That burning. Some of these mounds still repart of the walls of Athens which looks main near Benares, and have been cited towards Mount Hymettus, as well as by careless travellers as ruins of buildings some of the more ancient temples in that of unburned brick, a material for construccity, were also built of brick.
tion which appears never to have been In ancient Rome, if the recorded say- employed in India. ing of Augustus, that he found the city In Nipal, a hilly country north of Benof brick, and left it of marble, be of any gal, bricks are made of remarkable comauthority, the public buildings must have pactness of texture : they are of a brownbeen generally of baked brick; but this ish-red colour, and are very micaceous; material does not seem to have been so that the clay of which they are formmuch employed in the construction of ed, has probably originated from the deprivate houses, many of which were wat- composition of granite. Some of these, tled, or of wicker work, covered with from the East India Company's museum, clay, raised on low walls of unbaked are now before the Society. Not only bricks. Whatever works were erected by the texture of these bricks, but the elethe Romans, of flints, or of other rough gance of their ornamented surface, deunsquared stones, they were in the habit serve notice; the sharpness and depth of of interposing occasional courses of flat cutting are such as to make it probable thin bricks, to strengthen the building, that they were moulded plain, and that and to keep it upright. Many such ex- the ornaments were afterwards cut, beamples are to be found in our own coun- fore the process of burning. try, where permanent Roman stations oc- In China, bricks are made of blue clay,
The walls of Richborough, near more or less sandy : the specimens beSandwich, the tower supposed to have fore the Society have evidently not been been a lighthouse on the summit of burned; they nevertheless do not disturb Dover castle, the station of Garrienum, the clearness of water after lying in it (now Borough camp,) at the conflux of for many hours. When burned they bethe Yare and Waveney, in Norfolk, and come of rather a pale red, with a comthe walls at Lympne, near Hythe, are pact, almost semi-porcelanous texture. among the most perfect and remarkable. I am not sufficiently acquainted with All the Roman bricks, that I have seen, the history of the art of brick making, to are of a deep red colour, very compact, state to you the date and particulars of and well burned. They probably were its introduction into the different councomposed of natural clay, not containing tries of modern continental Europe. It lime, and merely sifted, either dry or by was certainly practised largely in Italy in washing over, in order to separate the the beginning of the fourteenth century; stones and coarser sand.
and Mr. Hope informs me, that the brick In Bengal, and generally in the wide buildings erected at this period in Tusalluvial valley of the Ganges, bricks are cany, and other parts of the north of the usual material for buildings of any Italy, exhibit, at the present day, the finest solidity; and they appear to have been specimens extant of brickwork. In Holused in this country from very high an- land and the Netherlands, from the scarcity tiquity, and to have been employed even of stone, brick was used at an early period, in the ornamental parts of architecture. and to a great extent, to supply the wants
Dr. Wilkins informs me, that bricks of a dense and rich population.
are constantly going forward there to obOn the north of Hillah, a town situ- tain bricks, make it difficult to decipher ated on the Euphrates, the first ruin that the original designs of the mound. In some meets the
eye of the traveller, is a mound places, the workmen have bored into the called Jumjuma, an epithet which, like solid mass, discovering on every hand Golgotha and Calvary, signifies, “the walls of burned bricks laid in lime mortar place of a skull." South of this is the fragments of alabaster vessels, fine earth, Amram hill, which is 1100 yards in enware, marble, and varnished tiles. Richlength, and 800 in breadth, and the figure discovered a colossal lion, standing on a of which nearly resembles that of a quad- pedestal of coarse granite of a grey corant. The elevation of this mound is lour, and of rude workmanship. This somewhat irregular, but at intervals it was on the north side of the mound; and rises to seventy feet above the level of immediately west of it are the ruins pethe plain. It is broken by deep ravines culiarly denominated the Kasr, and long winding furrows, and the whole Palace. appears one vast elevated mass of earth There is one remarkable difference bemixed with fragments of brick, pottery, tween the material of the Kasr, and that vitrifications, mortar, and bitumen. At of the Mujelibe and the Birs Nemroud. the foot of the narrowest and most ele- (See Visitor, 1841, pages 297 and 401.) vated part of the embankment, a number The latter piles are vast internal courses of urns
are cemented into the burned of sun-dried bricks, consolidated by the brick of the wall, which are filled with intervention of reeds and slime; but the ashes, intermingled with small fragments Kasr is formed of furnace-burned brick, of human bones.
with its necessary cements. Every brick A little to the north of the Amram hill, is has been found, on examination, to be the Kasr, or Palace, an august ruin, rising placed with its face downwards; and full seventy feet above the general level. where bitumen has been used, the bricks The whole of this mass is furrowed into of each course were covered with a layer deep ravines, intersecting each other in of bitumen, spread over with reeds, or every direction, and as the traveller passes laid in regular matting; and on this preover it, his feet sink into dust and rub- paration the faces of the succeeding courses bish. Every vestige discovered in it were imbedded. This agrees with the acshows it to have been composed of build count of Herodotus, who states that the ings superior to all the rest in this section bricks for the walls were made of the clay of the ruins, but the excavations which dug from the moat that surrounded them ;