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WALKERSPACH, in Geography, a river of Wur- 

 temberg, which runs into the Rems. 



WALKERTON, a town of Virginia, on the Matta- 

 pony ; 30 miles N.E. of Richmond. 



WALKING-FiKE. See Ignis Fatuus. 



WALKOOG, in Geography, a town of Holland; 10 

 miles N. of Alcmaer. 



WALKUFFA, in Botany, a tree which grows in the 

 Kolla, or hotteft part of Abyflinia. This does not flower 

 immediately after the rains, like the other Abyffinian trees, 

 that is, between the beginning of September and the Epi- 

 phany, but towards the middle of January it appears firft 

 covered with flowers. Although beautiful, it has no fmell, 

 and is found to be deftruftive to bees, fo that it is rooted 

 up in thofe countries that pay their revenue in honey. In 

 its appearance it refembles the Englifli Kentifh cherry-tree : 

 the wood immediately under the bark is white, but under 

 that a brownifli-yellow, fomewhat like cedar. Although 

 the- wood is heavy, it fwims in water, contrary to the opi- 

 nion of the natives. Mr. Bruce has given a botanical de- 

 fcription of this tree in the Appendix to his Travels. 



WALL, in ArchitcSuTe, Sec. a work of ftone, brick, or 

 the like, making the principal part of a building ; as 

 ferving both to enclofe it, and to fupport the roof, floors, 



ice. 



Walls, though built very thick and ftrong, and their 

 foundations laid deep, yet, if carried on (Iraight in a line, 

 are apt to lean, or fall ; and fuch as are built crooked, 

 though tliin and weak, are much more lafting. A wall 

 raifed over a river, on arches of pillars, fl;ands as firm as 

 others, whofe foundation is entire. 



Hence, it appears, that a wall built much thinner than 

 ufual, by only having at every twenty-feet diflance an angle 

 fet out about two feet, or more, in proportion to the height 

 of the wall ; or bv having, at the like diftance, a column, 

 or pilafter, erefted along with it, fix or eight inches on each 

 fide, over and above the thicknefs of the reft of the wall, 

 will be much ftronger than if five times the quantity of ma- 

 terialB were ufed in a ftraight wall. 



Walls are diftinguiflied into divers kinds, from the matter 

 of which they confift ; zs pla/IereJ or miid-'walli, brick-iualls, 

 Jione-vjalls, jlinl, or boulder-ivalls, and boarder-iualh. In 

 all which thefe general rules are to be regarded : 



1. That they be built exaftly perpendicular to the ground- 

 work. 



2. That the maffieft and heavieft of materials be the 

 loweft ; as being fitter to bear, than be borne. 



3. That the walls, as they rife, diminifli proportionally in 

 thicknefs, for eafe both of weight and expence. 



4. That certain courfes, or ledges, of more ftrengththan 

 the reft, be interlaid, like bones, to ftrengthen the whole 

 fabric. 



Mud and plaftered walls are chiefly ufed in ordinary 

 timber-buildings. Thefe walls, being quartered and lathed 

 between the timber, or fometimes lathed over all, are plaf- 

 tered over again with white mortar. 



In the conftruAing of brick-walls, which are the moft 

 important and ufual of any kind, it is neceflary to take par- 

 ticular care in laying and managing the materials ; that in 

 fummer they be laid as wet, and in winter as dry as poITible, 

 in order that they may be made to bind the better with the 

 mortar ; that in fummer, too, they be covered over as faft as 

 they are laid, in the view of guarding and preventing the 

 mortar and other matters from drying too quickly. That 

 in winter alfo, they be covered well, to proteft them from 

 heavy rain, fnow, and froft, which are all enemies to, and 

 greatly dellruftive of mortar ; that they be laid joint on 



joint, in the middle of the walls, as feldom as-may be ; lb 

 that good bond be made there as well as on the outfides. 

 Care is likewife to be taken that the angles be firmly bound, 

 as they may be confidered as the nerves and finews of ttie 

 whole fabric. In order to which, in working up fuch walls, 

 it is not advifable to raife any of them above eight feet in 

 height, before the the next adjoining ones be brought up to 

 them ; fo that a good bond may be made as the work pro- 

 ceeds. It may be noticed that a wall of this kind, a brick 

 and a half thick, with the joint, will be in breadth fourteen 

 inches, or very near it ; and in which one hundred and fifty, 

 or one hundred and fixty bricks will lay a yard fquare, mea- 

 fured on the face of the wall ; and that to the fquare of ten 

 feet, feventeen or eighteen hundred bricks are ufually 

 allowed. 



In building a houfe in the city of London, the walls are 

 to be of fuch thicknefles as are enjoined by aft of parliament. 

 See Building, and PARTY-waZ/j-. 



In the forming of ftone-walls, the fame fort of care and 

 attention is requifite in protefting and preferving them from 

 the injurious effefts of external caufes of the above kinds, 

 ai well as in that of building them in a folid and feoure 

 manner. The foundations are alfo to be well looked to. 

 The two fides or faces are to be evenly carried up, and the 

 fillings to be put well and fufficiently in the middle parts be- 

 tween them, proper long ftones being occafionally placed 

 acrofs, to bind the two faces fecurely together, and prevent 

 their feparating. Thefe attentions are equally neceflary in 

 the ftone-walls of buildings, as in thofe of the better fort of 

 ftone-walls for other ufes and purpofes. 



In the raifing of double walls in this way, as defences in 

 fields and grounds, which is fometimes done, the faces may 

 be bound in, where proper ftones as throughs cannot be had, 

 by thin layers or ftrips of the ftones, laid in mortar, at about 

 every fourteen inches in height, as they rile, the mortar 

 being in fuch cafes kept foft, fo as that it may lay firm hold 

 of the ftones. And with the fimilar intention of keeping 

 them upright, and preventing their feparation, they may be 

 carried up with a confiderable inclination inward, towards 

 each other, tapering upward as they rife, in the proportion 

 of about one inch, on each fide, to every foot or foot and 

 a half of rife or height. 



In raifing fingle field-walls, which is not uncommon in 

 fome high fituations, and where large ftones are met with in 

 plenty upon the furface of the land, two benefits are attain- 

 ed, in fome cafes, by running them up in as open a manner 

 as the nature of the materials will permit, fo as to form good 

 work. Such open-work walls are lefs liable to be thrown 

 down by the winds in fuch expofed fituations, than thofe of 

 the clofe kind ; which is an inconvenience to which fingle 

 walls are expofed in fuch cafes ; as by means of part of the 

 blall palling throilgh them, its force is confiderably dimi- 

 niflied. And the wild mountain-breeds of flieep are lefs apt 

 to fcale walls fo conftrufted, than they are thofe which are 

 formed in a clofer manner, and liave a more folid appear- 

 ance. This is particularly the cafe if they belaid with fmall 

 ftones loofely on the tops. 



It is faid that ftone-walls of the field fort, which are apt 

 to ftiatter with froft s, if laid only a foot deep in the middle 

 with mortar, or even road-lf uff made into it, are held well 

 together, and become durable. 



Flint, or boulder-walls, are faid to be much ufed, in fome 

 parts of the counties of Suflex and Kent, for fence-walls in 

 furrounding court-yards, gardens, and other fuch places. 

 In performing the work of building them, a right and left- 

 handed man fuits well, as they have the hod of mortar 

 poured down upon the work, which they part between 

 12 them, 



