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303

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F tlii s rans P are,!C 7 to that singular stone called oculus mundi."'ill i, e ,lUn<Jl ', the weight of air, under proper management,capable of making several sorts of glues penetrate"'Hi ; ,|j laris ; and not only this, but baked earth, wood,° c <:asi 0n l ' ler bodies porous enough to admit water on this

* s °ft ^ Paris, diluted with water into the consistence of["Slant op . n P aste > quickly sets or grows firm, and, at the” it» ««»:-- i --- bulk increased; for Mr. Boylefilled with the fluid mixture,

b.

fon^j setting, has its bulk""d closei’ t " at a glass vessel,

"lOSgJ “ gtuoo vcaoci, Jiiicu tvuu uic uuiu miAtuic

a ri J "topped, bursts while the mixture sets, and some'

ought the cracks.

S:

Tltj s T'antity of water issues thro

( tr| i st a tg^. ans ' on °f the plaster, in passing from a soft to a6>C(:(! llent ’ 18 one °f its valuable properties, rendering it an^I'er eart^ 1 ^ 6 - 1 ' ^ or cavities in sundry works, where

Rifely ‘y mixtures would shrink and leave vacuities, orft j s e Parate from the adjoining parts.

["glit j^Ptohable, also, that this expansion of the plasterl0 >is it r aae to contribute to the elegance of the impres-t r 1 r| i;ut fcI . eU | es f r om medals, &c., by properly confining the"tes of fi’ 1 lat * ts expansion may force it into the minutestoff 1Ce ' e fo u >'e ; the expansion of the matter doing thelt L Ca vb;„ as . t * ie pressure by which the wax is forced into

aSer 0 Vp a - Sea1-

-this s„i 1 ,r aris promotes the fusion of forged iron.

used for taking casts and'be a" 8 , 1 . 10111 figures, busts, medals, &c., as it is adapted

'Oil

t ^ssiftft ^^stance is commonly

0 theT\ from % u

ov ®ai n g use of making both casts and moulds for

u >«m.

gp? 1 ?’ ^hich 1 * 0 a P laster of a coarser sort than the plaster ofLl \, 1S 30rae tiines used in this country for floors in

"^b-ston J0l,ses > and for corn-granaries : it is made of ane > taken

tl,

>e ,

■dde oF‘\. talten ou ' °f quarries, which are generally at. ^“‘11, much like the stone of which Dutch terras"tone is burnt like lime, becomes white

by

iTS&tS 18 _,___

■q? e . : ' v ben ’ Y^ 6 ! 1 m * xe| f with water, does not ferment likei V| ,t the q u CO i > la beat into a fine powder ; and, when■lf r a Pplied ntlt ^ a b out a bushel is put into a tub, and< >tir *d ...

lita e lin S> as

"'dl s t w >!) ! e,i to it till it becomes liquid ; in this state it isthat, a re<1 with a stick, and used immediately ; for, in less?.°tlii n ~ < l Ua rter 0 f an hour, it becomes hard and good forit will not bear being mixed a second time, like

Fl <X>rs, such floors as are constituted of plaster,l' e n y , ,^'om such lime as possesses a strong binding pro-

%

j»._ — ««io t*o a. winding piu -

a Ford; n ^ are highly useful in cottages and farm-houses,

e i,,: , lilUc h security against fire. In constructingJ ists are lam bi._ _i —__ j — -~

eta.

th,

' v bicf 8 s °rt S of aie ^ a ‘ d * n tl ,e usual manner, and on them isis f t * the pi strong reed, found in Huntingdonshire , uponOtfyT-applied; but in order to save it, theres N ® c rpvift. a . 1 ’ n coat of common lime laid on first, to fillCm , . out

“t i 1 ' 1 a "

V1C «S and inequalities. On this the plaster is thenWith' 2' t0 the thickness of about two inches, being lam,, l be hq lUuc 'i expedition as possible. The plaster is sor^^Pens, 8 m dle midland districts, at 6<i. the bushel ., an

. „ ie laying it on, if burnt and prepared,

««, a Z d i but if to be burnt and prepared by

and! as much more. These floors are sald t0 , . mayta ade?' ea P - "Where reeds cannot be procur ,^ of t!) ; sl° n atu 8e < but they come much higher. q^ ut .

^ahltp Uc ^' ’ n us® in Nottinghamshire , as we

NeJ i : t "bore the upper floors of the farm-housesNhu,.,. k ' ,rid3 of floors should

"'1,(1, OtlRgr -

s "‘S small houses, both ofr'e, 8 “eing cheap, readily laid,

be more attended to inof the cottage and otherand at the same time

PLASTERER, a workman to whom the decorative partof architecture owes a considerable portion of its effect, andwhose art is required in every department of building. Inordinary edifices, he lays the ceilings, and covers the walls-with a smooth coat, to render them sightly, and prevent theobtrusion of air through any crevices left by the bricklayerand carpenter, or occasioned by settliug. In buildings ofgreater importance, in addition to this service, he also fur-nishes mouldings, ornamental as well as plain, and covers theexterior walls with stucco, imitative of stone.

The tools of a plasterer consist of a spade, or shovel, ofthe usual-description ; a rake, with two or three prongs, bentdownwards from the line of the handle, for mixing the hairand mortar together; trowels of two kinds, and various sizes ;stopping and picking-out tools ; rules called straight-edges ;and wood models.

Plasterers’ trowels are more neatly made than the tools ofthe same name used by other artificers; they are of twosorts, viz., the laying and smoothing tool, which consists of aflat piece of hardened iron, about ten inches in length, andtwo inches and a half wide, very thin, and ground to a semi-circular shape at one end, but left square at the other : onthe back of the plate, near the square end, is riveted a smalliron rod, with two legs, one of which is fixed to the plate ;and, to the other, a round wooden handle is adapted : withthis tool, all the first coats-of plastering are laid on, as arealso the last, or the setting, as it is technically denominated.The other kind of trowels, which are made of three or foursizes, are for gauging the fine stuff and plaster used informing cornices, mouldings, &c. The longest size of theseis about seven inches in length on the plate, which is ofpolished steel, and two inches and three-quarters broad atthe heel, diverging gradually to a point ; to the heel, orbroad end, a handle is adapted, commonly of mahogany, witha deep brass ferule. The smaller trowels are fitted up in asimilar manner, only they gradually vary in size downwardsto the length of two or three inches.

TLe stopping and picking-out tools are of polished steel, ofvarious sizes, though most generally about seven or eightinches in length, and half an inch in breadth, flattened atbotli ends, and ground away to somewhat of a round. Thesetools are used in modelling and finishing mitres and returnsto cornices, as likewise in filling up and perfecting the orna-ments at their joinings.

The straight-edges are used for keeping the work in aneven or perpendicular line ; and the models, or moulds, arefor running plain mouldings, cornices, 8tc. Of these last,the plasterer requires a great number, as very little of hisfinishing can be completed without them. With a goodmould, an adept in his profession may execute most exquisitemouldings, possessing a sharpness and breadtli unequalled byany other method now practised.

Good workmen keep their tools very clean ; after beingused, they are wiped free from the plaster that cleaves tothem, before they are put away, and they are daily polishedby the hawk-boys.

Plasterers have technical divisions of their work, by which

I

its quality is designated, and from which its value is ascer-tained ; as, lathing ; laying ; priching-up; lathing , laying,and set; lathing, floating, and set; screed; set or putty; \

rendering and set, or rendering, floated, and set; trowelledstucco, &c., each of which will be found fully described in jthe next article. See Plastering. j

Plasterers’ work is measured and valued by persons known ’in the trade as measurers, though popularly denominatedsurveyors. All common plastering is measured by the squareyard of nine feet; this includes the partitions, nails, and

i