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ceilings of rooms, inside and exterior stuccoing, &c. Cor-nices are measured by the foot superficial, their numbersbeing girt to obtain their width; while their length is takenj at that of the cornice. Running measures consist of heads,j quirks, arrises, and small mouldings. Ornamental cornicesj are frequently valued by the foot run.

! As the labour on plasterer’s work is frequently a greaterconsideration than the materials used, it is necessary for themaster to be attentive to the noting down the time occupiedby his men in executing their several pieces of plastering ;otherwise he will be unable to put an adequate value on hiswork.

PLASTERING, the art of covering the walls and ceilingsof a house, or other edifice, with a composition, of whichthe ground-work is lime and hair-mortar, finished with acoating of finer materials. It is of various kinds ; as whitelime and hair mortar on bare walls ; the same on laths, as inj partitioning and plain ceiling ; renewing the insides of walls,

I or double-partition walls; rough-casting on heart-laths ;plastering on brick-work, with finishing-mortar, in imitationof stone-work, and the like upon heart-laths ; modelling andcasting ornamental and plain mouldings ; and making andpolishing the scagliola for columns of wood or brick andtheir antte.

In all the operations of plastering, lime forms an extensivearticle, as it pervades the whole ; and for its nature, pro-perties, and preparation, the reader is referred to the wordLime ; suffice it here to remark, that most of the lime usedin London is prepared from chalk, and is brought thitherfrom Purfleet, in Kent; but for stuccoing, and other workrequiring strength and permanency, that which is made atDorking, in Surrey , has a decided pre-eminence.

Next to lime, the plasterer depends much on what iscalled plaster of Paris (see that article) ; for this aloneenables him to give the required form and finish to all thesuperior parts of his business. With this he makes hisornaments and cornices ; and he also* mixes it with the limefor filling up the concluding coat to the walls and ceilings ofrooms. The name of this composition is derived from thecircumstance of its abounding in the hills of Montmartre , inthe environs of the French capital ; but what is chiefly usedin London is prepared from a sulphate of lime dug inDerbyshire.

Cements used by plasterers for inside work are of two orthree kinds ; the first is called lime and hair, or coarse stuff,

' and is prepared as common mortar, only with the addition ofj hair from the tan-yards being mixed with it. The mortar is

I first mixed with the requisite quantity of sand, and then the

hair is worked in by the labourer with the rake.

Next to this is fine stuff, consisting of pure lime slakedwith a small quantity of water, and then, without any extra-neous addition, supersaturated with water, and put into atub in a half-fluid state, where it remains till the water isevaporated. In particular cases, a small portion of hair isj sometimes worked into this fine stuff) before it is laid on.

For inside walls, this fine stuff is mixed with very finewashed sand, in the proportion of one part sand to threeparts of fine-stuff, and then it obtains the name of troweled,or bastard stucco, with which all walls intended to bepainted are finished. Gauge-stuff consists of three-fifths offine-stuff and one-fifth , of plaster of Paris, mixed togetheri with water, in small quantities at a time, to render it moreready to set, or fix itself. This cement is mostly used informing cornices and mouldings run with a wooden model.When great expedition is requisite, plasterers gauge all their| mortars with plaster of Paris, which enables them to proceed: with their work, because it sets as soon as laid on.

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Next to the materials, the technical divisions of t> ,e Pterers’ work claim attention, and are as follow , th e

1. Lathing: this operation consists in nailing lntbs^ -nir®ceiling or partition. If the laths be of oak, they will jewrought-iron nails ; but if of deal, cast-iron nail 9 - (te lused. Those mostly used in London are of fir, inl 'j ja th 9from the Baltic and America , in pieces called staves fl ,jthare made in'three-foot and four-foot lengths; an ’ Jntb'

respect to their thickness and strength, are either sing 1 ’ „(ii- - - ° - ■ -e 9t

and-half, or double. The single are the thin 11 gfl e'cheapest ; those called lath-and-half are supposed W rP t« ,icethird thicker than the single ; and the double laths * ,j u s®their thickness. - - -- - - - - ,n

In lathing ceilings, the plasterer sho h 9

both the lengths alluded to ; and, in nailing them ^cbshould so dispose them that the joints may be ot

broken as possible, that they may have the strong e ( ^ the/tie, and thereby strengthen the plastering withare to be covered. The thinnest laths are used in Pand the strongest for ceilings. See Lath. r( j e r, l *' e

Having nailed the laths in their appropriate ng

next business is to cover them with the piaster, ^which, the most simple and common operation is tim [jin 9

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2. Laying : this consists in spreading a single c0 ^ ue r'

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and hair all over a ceiling, or partition ; carefully

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to keep it even and smooth in every direction. ■^* 11cheapest kind of plastering. gT 99

3. Pricking-up is performed in the same ma nn <. eC tk' rlforegoing, but it is only a preliminary to a more p # jj o ff \of work. After the plaster is laid on, it is crosse cO' 1with the end of a lath, to give it a key, or tie, t°

that is to be laid upon it. g e r b e,n *

4. Lathing, laying, and set, is when the work, v/b e ^

lathed, is covered with one coat of lime and hair, ° v ;that is sufficiently dry, a thin and smooth coat is 3 P p tl y^it, consisting of lime only, or, as the workmen ca wb 1 ^

or set. This coat is spread with the smoothing-*^ h* a

the workman uses with his right hand, while J n ^ r j 9 tles- ^he is furnished with a large flat brush of hog 9 g,. a \v 9 n dhe lays on the putty, or set, with the trowel, e gVef it, 9brush, dipped in water, backwards and forwar •

thus produces a surface tolerably even for e ^ ea ? e foreg® 1 .^

5. Lathing, floating, and set, differs from ' ge t,

in having the first coat pricked up to receive ‘ 0 pei' ilt '” g ’is here called the floating. In performing th> 9 . a ig|it- ethe plasterer is provided with a substantia jnu 9t ^, e

frequently from ten to twelve feet in length, w ^ gate dhandled by two workmen. All the parts to f t h e S 9 ,then tried by a plumb-line, to ascertain ) v ' e . [)C y a pP e v iperfectly flat and level; and wherever any de c 0 f lim e .the hollow is filled up with a trowel-full, or , n:l0 | ie n tb eS jhair only ; this is termed filling-out; to beliminanes are settled, the screeds are begun ^ ^ a bo ut s ’ “

I1IIIIU1 HjO tut/ b»»v/ OVf 1/01*0 “• v - t j|, JJl/W

6. A screed signifies a style of lime and ’fanvfi"8

ic distance oi auuut Linee ui iuui ^ ( ^ ^

vertical direction all round the partitions an ” up . , 9 |jWhen they are all formed, the intervals a> ^ a re ^ gtllime and hair, called by the workman stuff t _ e dg e 19 , p erwith the face of the screeds. The stra ,'| c | 1 a ll th e ^worked horizontally over the screeds, by w 1 ' n,er 'j 0 n ' 3fluous stuff, projecting beyond themremoved, and a plain surface is pioduced. . ji<rg ° s fa 1,1

termed floating, and may be applied to t g e scf,. nl , up

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termeu noating, ana may ue - . t jje a >*r

partitions or upright walls, by first an^ ^ pfll u s ' t0

the direction of tlve breadth of the apar ^ oare is rthe intervals as above described. As g re