1000000030

S·

of foulh larilude ; oeing about

700

miles long from

eafl to IVen, and one huoJred broad.

jAVELIN, in anliquily, a Con of Cpear, five feel and

half long; lhe fhaft of \Vhich \Vas of wood, IVilh a

lIee! point.

Every Coldier, in the Roman armies, had Ceven of

Ihefe; which were very lighl and fIender.

JAUNDICE, in medicine. SeeMEDlcINE.

].'\W, in analomy. See ANAToMY, p. 159,

J.".

WER, a city of Silefia, capital of lhe duchy of JalV–

er, firualed in 16° 12' E. long, and

S' N. Ial.

JAZY,

a cily of European Turky, capilal of Moldavia,

fitUaled on theriver Pruth, in E. long. 28°

40"

N.lal.

47°

IBER[S, in bOlaay, a genus of the tetradynamia fili–

culofa claf!. The corclla is irregular,-the tlVO out–

mor! petals Iieing larger!; and the pod is emarginaled,

and cont1ins many feeds. There are tlVelve fpecies,

only one of which,

viz.

Ihe medicaulis or rock·crelfe,

is a nalive of Britain.

lBEX,

io zoology. See

CAPu.

IB[S, in ornilhology. 8ee TANTALUS.

ICE, in phyfiology, a Colid, lrafparent, andbrínle body,

formed oHome fluid, partieularIy water, by means of

cold. See FROST and FREEZING.

Theyounger Lemery obCerves, that ice ís only are–

er!ablifhment of the pans of water in their natural

lIate; tRat the mere abCence of 6re is Cufficient to ac–

eouot for this re-er!ablifhment; and that the fluidity

of water isa real fufion, like that of metals expoCed to

the 6re; differing ooly io this, that a greater quantity

of fire is oecelfary to the ooethan the other. Gallileo

was' the firft that obCerved ice tO be lighter than the wa–

ter which compoCed it: aod hence it happeos, that ice

floats upoo water, its Cpeei6e gravity being to that of

water as eight to nioe. This rarefallion of ice is owing

to the air-bubbles produeed in the IVater by freezing;

and beiog eorrfiderably large in proponion tO the water

frozen, render the body fo much Cpeei6cally lighter:

and theCe air-oubbles growiog large, acquire a great

expaofive power, fo as to burr! the containing velfels,

though ever

fIrong.

Iet' HousE, a buildiog contrived to preCerve ice for the

oCe of a family in the Cummer-CeaCoo.

Ice-houCes are more generaHy uCed in warm couotries

than with us; particularIy in ltaly, ...here the meaner!

perCon who renlS ahouCe, has his vault or cellar for ice. ,

As to the fituation, it ought tO be placed upon a dry

fpot of ground; becauCe where-ever there is

momu.re

the ice wiII melt : therefore in aH flrong lands whreh

retaio the wet, 100 much pains caonot be taken 10 make

drains all round

th~m.

The place fhould alCo be ele–

vated, and as mucn expoCed to lhe Cun and air as pof–

fible.

As to the figure ofthe building, that may beaccord–

iog

the faney of the owoer; but a circular form is

mon proper for Ihe well in which the iceis to be.preCer–

ved, which fhould be of a fize and deplh proporuonable

to the quantilY to be kept; for it is proper to

ha~e

)¡rge eoough to cootaio ice for tWO years conCumptlon,

VOL.

Il.

No.61.

tha~ if,~

llIild \'Jinter fllOuld happen, in whiel. litl le

or no ree ISto oe bad, there may ue a Hock

Cupply

theIVant. Al the boltom of the well, Iherc fIwuld ue

~pace

of aGout IWO fcet decp, left 10

rec~i"e

any

mOlflure that maydrainfrom the ice; over this Cpace

fhould be placed • flrong wooden

gr.lc,

and from

thence a Cmall drain fhould oc

I.id

under grounrl, to

carry off the we!. The fides of lhe well fIlOuld be

ouilt with'brick Or

non~,

at leall tl'lO bricks thick' fo,

the lhicker it is, the

leCs

danger there will be

the

well being affeéted by any external cauCe. 'When the

lVell is brought up wilhin three feet of the furface,

there fhould be another outer·arehor wall be!'un whieh

fhould be carried up to the heighl of thetO? of'the in–

tended areh of the well; and ir lhere be • fecond areh

turned over this wall, il wiU add to thegoodneCs of ¡he

houfe: the roofmur! be high enough above theinner areh

admit ofa

door.~vay

to getout Ihe ice. If the building

to be covered Wllh fIates or IIles, reeds fhould be laid

conGde~ably t~lick

under them, to keep out Ihe Cun

aod eXlernal alr; and if theCe reeds are laid the thick–

nefs of Gx or eight inehes, and plafIcred over IVilh lime

and hair, there will be no danger of lhe heat gettin¡:

through them. The external wall may be built in

what form the proprietor pleafes; and as theCe ice–

houfes are placed in gardens, they are Cometimes

contrived as to have an handfome aIcove·Ceat in front,

with a fmall door behind it, througli whieh a perfon

mignt enter to take out theice; and a large door on

the other fide, fronling the north, wilh a porch

wide enough for a CmaIl cart to back, in order to

fhool down the ice near the mouth of the well, which

need not be more thao llVO feet diameter, and a flone

fo cootrived as to fhut it up io the e¡¡aéter! manner:

all the vacant fpace aboye and between this and the

large door fhould be filled up wilh barley-fIraw. The

buildioZ tbus finifhed, fIlOuld have lime to dry before

the ice is put into it.

It is tO be ooCerved, that "J0n the wooden grate, at

the bottom of the well, there fhould be laid fome

fOlall faggots; and if upon th& a layer of reed! is

placed Cmooth for the ice to lie upon, il wiU be belter

than IIraw, which is commonly uCed. As to the

ehoice of the ice, the tliinoer itis, the eafier it may be

broken to powder; for the Cmaller it is broken, the

better it ",ill unite when put into the well. lo putting

it in, care mufl be laken to ram it as

c\of~

as poOible;

2nd alfo to allow a vacaney of two inches, all round,

next the 6de of the WfU, tO gil'e palfage to any moi–

lIure occafioned by the melting of Come of the ice.

Wheo the ice is put ioto the \Vell, ifa linle falt-petre

be mixed with it at every ten inches or a foot io thick–

ocCs, it wiII cauCe it to unite more clofely ioto a Colid

mafs.

ICHNEUMON, in zoology. SeeVIVEUA.

ICHNEuMoN is alCo the name of agenu! ofnies, of the

hymeooplera order.

haS

tongue; the antennz:

have above thirty joints; the abdomen, in moll of the

fpecies, is petiolated; and it has a fling in the tail

incIoCed in a double-valved eylindrieallheath. There

8 Z