JAP
55
JOI
I
J,
f Lifting Jack, in mechanics, a portable machine
0 j. raising great weights through a small space. It consistsat) , a r a°k and pinion inclosed within a strong wooden case,g ,rhe power is applied by means of a winch or handleis f Upon *ke axis of the pinion ; the upper end of the racka . orme d into two horns, to take the better hold of thelat ° ,, to elevated ; and from the end two prongs projectare ra y through a longitudinal groove in the case, whichthe L ' Se< ^ u P on occasions when there is not room to introduceov "* aC k beneath the load. To prevent the labourers beingrpowered, there is a racket wheel and pall on the axis ofhe Pinion.
Arch, an arch of only one brick in thickness.
K in the Box, a large wooden solid screw, turning in
g j '°°' v one, which forms the upper part of a wooden box,o a Ped lik e the frustum of a pyramid; it is used by meansana 7 ei ' 3 ’ Passing through holes in it, as a press in packing,j 0r other purposes.
, CK Plane, a plane about 18 inches in length, used for
tak
a Xe.
ln g off the rough of the saw, or the irregularities of the
tl ' an .d planing off any inequalities, to prepare the stuff forjtrying plane.
fiv, i ° K Palter, a short rafter, such as those which are*gto the hips.
the Ptbs, in a groin, or in a polygonal domic ceiling, arer| bs that are fixed upon the hips,length ^' IMBEK > an y timber that is interrupted in its whole
sotn
m . , _ coarse-grained wood brought from India ,
IA 'I* 163 us ed in cabinet-work and turnery.tl le . “tl>S (French ) the sides of an aperture, which connectJaT° S *^ es P le w all.
a Pert' lB the two vertical linings of a door-way or
Ja ^ "bicli connect the two walls.of a It Posts, such as are sometimes introduced on the sidet'cul. .? 01 ’ ' n tn'der to fix the jamb linings. They are par-It 1 ^ Bse< ^ when the partition is of wood.th e j 0 ' av *ng been noticed by Mr. T. N. Parker how rapidlyto ^ «nds of door-posts decayed where they were exposedis tr .’ ’ ll e contrived a cast-iron socket for them, whichiin,. od V use( l in Shropshire , and might be generallywith advantage. These sockets are cast by thetost 0 i "bale company; they weigh only 71bs. the pair, and. Jaiibo,, 2 ^ 1 per pound.
buil dinrr | SES , In stone walls, such as are employed innat e a,’ 3 t le s * ( les of an aperture, in doing which, every alter-' v all s ° Ue ou gbt to be inserted the whole thickness of the
for th^^'^J’ a machine used in Hindostan for raising waterJAia P , U , r l’ ose irrigating lands.
‘he t^NlNG, the art of pain
Ul'l -me ui l <JI painting and varnishing, after
Luli es nn T er Practised by the natives of Japan , in the Eastbeautify- ^ is employed for the purpose of preserving and"'ell aa n ® v arious articles, usually of wood and metal, asPrepared*p lper ’ leather, and cloth, when they are properlyfind j a or the purpose. Those articles we most commonlyboxes aie pieces of household furniture, cabinet-work,
I!* 0 * artili 1 i in< , la > !. ra y 8 > screens, &c., and, very generally,aia teri a i a C e , 3 . ma( l e of any of the above-mentioned or similar> which it may be desired to preserve from moisture.
This it is admirably adapted to effect, from its dryingvery hard, and being impervious to water at all moderatetemperatures, even to boiling in some cases; but it may beemployed on any dry substance that is sufficiently inflexibleto prevent the japan from being cracked or forced off.
JERKIN HEAD, the end of a roof that is not hippeddown to the level of the opposite adjoining walls ; the gablebeing carried higher than the level of the said walls.
JET D’EAU, (French ) a fountain, or ornamented jet,throwing up a stream of water to some height in the air.See Fountain.
JETTEE, Jetty, or Jutty, (French ) the border madearound the stilts under a pier, consisting of piles and planks,stones filling up the interstices, to secure the whole foun-dation.
Also the projecting portion of a building, such as the over-hanging story of ancient timber houses.
JIB-DOOR, a door so constructed as to have the samecontinuity of surface with that of the partition in which itstands. The use of a jib-door is to preserve the symmetryof an apartment, where only one door is wanted, nearer toone end of the partition than the other. Instead of a jib-door, a real door and a false one may be used. Where jib-doors are used, it is obvious that they must be concealed asmuch as possible.
JOGGLE, the joint of two bodies, so constructed as toprevent them from sliding past each other, by the applicationof a force in a direction perpendicular to the two pressuresby which they are held together. The struts of a roof arejoggled into the truss-posts and into the rafters ; when con-fined by mortise and tenon, the pressure which keeps themtogether is that of the rafter and the re-action of the truss-post. The same is also applied to the step and platformstones of a geometrical stair.
Joggle Piece, the truss-post in a roof, when formed toreceive a brace or strut, with a joggle.
JOINER, the workman who joins wood for the finishingof buildings.
JOINERY, in civil architecture, the art of framing orjoining wood together, for internal and external finishingsof houses ; thus the coverings and linings of rough walls, orthe coverings of rough timbers, and the construction ofdoors, windows, and stairs, are joiners’ work.
Joinery requires much more accurate and nice workman-ship than carpentry; the latter consists only of roughtimbers, used in supporting the various parts of an edifice :joinery is therefore used by way of decoration, and beingalways near to the eye, and consequently liable to inspection,requires that the joints should be fitted together with theutmost care, and the surfaces made smooth.
The wood used is called stuff, and is previously formed bythe pit-saw into rectangular prisms, which are denominatedbattens, boards, or planks, according to their breadths.Battens run from two to seven inches wide ; boards fromseven to nine inches wide ; and planks from nine inches toany greater breadth that can be cut out of a piece of wood.
The operations of joinery consist of forming surfaces ofvarious kinds, also of grooving, rebating, and moulding, andof mortising and tenoning ; and lastly, of joining two orseveral pieces together, so as to form a frame or solid mass.