M 0 R

214

M 0 R

A house built during the third period still exists at Seville ,which was the residence of a Moorish Arab chieftain ; thewhole is most voluptuously contrived for a warm climate, andis in the most perfect state of preservation, though upwardsof 500 years old ; one of the apartments is almost perfect ofits kind. The form resembles a double cube, the one placedabove the other, its height about 60, and its length andbreadth about 30 feet. The ornaments begin at about 10 feetfrom the floor, and are continued to the top of the room : theyconsist of a kind of variegated network of stucco, designedwith the most perfect regularity, and yet most admirablevariety in the patterns and the interlacings of each. Thisedifice has often been adduced as an instance of the wonderfulsuperiority of the Arabs over the modern Spaniards in theart of building.”

There is one very ancient and remarkable building whichwe have not here described, but which may not be passed overwithout notice ; we allude to the Caaba , of which a descrip-tion will be found under that head.

For further and more detailed descriptions of this style ofbuilding, we refer the reader to the elaborate works of Jonesand Murphy.

MOOR-STONE, a very remarkable stone, found in Corn-wall , and some other parts of England, used in the coarserworks of modern builders. It is, in fact, a white granite,and is a very valuable stone. It is very coarse and rude,but has beautiful congeries of variously constructed anddifferently figured particles, not diffused among, or runninginto one another, but each pure and distinct, though firmlycohering with whatever it comes in contact. Its coloursare principally black and white : the white are of a softmarble texture, and opaque, formed into large congeries, andemulating a sort of tabulated structure ; among these aremany of a pure crystalline splendour and transparence ; andin some are lodged, in different directions, many small flakymasses of pure talcs, of several colours ; some are whollypellucid, others of an opaque white, others of the colour ofbrown crystal, and a vast number perfectly black. It isfound in immense strata in some parts of Ireland , but is dis-regarded there.

It is found with us in Devonshire, Cornwall , and someother counties ; and brought thence in vast quantities toLondon . It never forms any whole strata there, but isfound on the surface of the earth, in immense and unman-ageable masses ; to separate these, and render them portable,a hole is dug in some part of the mass, which being sur-rounded with a ridge of clay, is filled up with water ; thisby degrees soaks in, and finding its way into the imper-ceptible cracks, so far loosens the cohesion of the particles,that the day after, on driving a large wedge into the hole,the stone breaks into two or more pieces. It is used inLondon for the steps of public buildings, and on otheroccasions, where great strength and hardness are required.

MOOT - IIALL. Moor - House, a town-hall ; hall ofjudgment. In the moot-halls, formerly connected with theinns of court, imaginary or moot-cases were argued by thestudents at law.

MORESK, or MORESQUE, (from the Spanish morisco,)a kind of painting, carving, &c. done after the manner of theMoors, consisting of several grotesque pieces and compart-ments promiscuously intermingled, not containing any perfectfigure of a man or other animal, but a wild resemblance ofbirds, beasts, trees, &c.

They are also called arabesques, and are particularly usedin embroideries, damask-work, &c.

MORTAR (from the Dutch morier, cement) in architecture,a composition of lime, sand, &c. mixed with water.

In the construction of works in masonry, some k‘ ncementitious matter is generally employed for connectme,. eJ)stones together, and rendering them firm and compact. ' <,the works are to be exposed to the action of w r ater in'® 0 fately after being built, this cementitious matter must ^such a nature, that it will harden under water. Hence 1 .j|that we have occasion for two kinds of mortar, one Off-set and harden under water, called by Smeaton a jj,mortar, or cement; and common mortar, for ordinary aings. See Mortar, Hydraulic. !)C j

Common mortar is the substance placed between the s ^ ,or bricks of a building, to cement them together, and ^cause them to retain their places, and give strength j ;stability to the edifice. Mortar is essentially comp 08 ®^lime and silicious sand, the first being in the state ol hy a jor slacked lime : the sand is used of different deg re ^fineness. The hardness of mortar is owing to theconversion of the hydrate of lime into carbonate o ‘which takes place very slowly by the absorption of calacid gas from the atmosphere ; in this state it adheres |,firmly to the particles of silica diffused through it, an 1 * ^ ■■are strongly united with the material employed in |building. . a <r6 ij

In order that this change may occur with adva ‘ to o;\certain conditions are requisite : if the mortar dr> eaquickly, the carbonate formed will remain much divide ^ ^will not acquire the necessary adhesive property; *f aother hand, the mortar be placed under water, a p 01 0

the lime will gradually dissolve, what remains will rf jllcarbonate with great difficulty, and the particles of s» n j, e ptbe isolated. If, on the contrary, the mortar be l° n ^j 0 ,vl/moist and exposed to the air, the carbonic acid gas acts $but incessantly on the lime, the water of which b^ fiiflgradually saturated with it, and this being transferred jnlime, it is converted into almost a crystalline carboi*‘ 9 tsuccessive portions or layers, and these adhere v t l |flSforce to the particles of sand. It follows, from to 0

been stated, that buildings erected when the weatl* e ^ gr '''hot are less stable than those which are con . 8tru S.>^the year ; but it is to be observed, that during f> 0i ; c ,to the freezing of the water, the absorption of carb° y e<>is not only stopped, but the solidity of the mortar it a

by the freezing or crystallization of the water.

Much has been said as to the extreme hardness of \V i,sand it is supposed that some secret met .

mortar,

adopted

in its preparation ; but

somethe fact

may .

pr °'

accounted for by merely referring to the circumsta n i a g] . (1 i>l | tthe long exposure which it has undergone in c ° n ?'j,jg ^masses has given it the opportunity of slowly ac aI) d d*"'^carbonic acid from the air, upon which its hardness j s >tIt is to be observed, that lime w - w tl 1 '

by

,o s '

bility depend. It is imu ,

sufficiently burnt, or lime which has been slacke ^moisture which it has acquired by exposure to 1 ^

ed 14 "10

or

she l

, fillO

pliere, cannot form good mortar: the first hasdeprived of the carbonic acid which it is requisd®slowly from the air; and the latter has re-acquu' rcircumstances which diminish instead of increaseof the mortar. ,

Other materials, such as limestone, marble, chat ^ gge :may be used to burn for lime or common mortar, at jj • atances being composed chiefly of lime and carbon’ 0 ‘ sl) fiSif a piece of one of them be slowly burnt or cal° int V a ci®’ j|expel the whole, or nearly the whole, of its earn ^ aloses about 44 per cent, of its weight ; and w 9 vV° iquantity of water is added to the calcined matte ’fier c ]„ifgives out heat, and falls into a finely-dividedslacked lime. I he bulk of the powder is abou