Mrs. (Jane Haldimand) Marcet.

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OeUUttes. Stdts formed by the combination of any base with gallic acid.

Galvanism. A new science which offers a variety of phenomena, resulting
from diflferent conductors of electricity placed ^in different circumstances
of contact; particularly the nerves of the animal body.

Gas. Ail solid substances when converted into permanently elastic fluids by
caloric, are called gases.

Gaseous. Having the nature and properties of sas. .

Gasometer^ A name given to a variety of utensils and apparatus contrived to
measure, collect, preserve, or mix the different gases. An apparatus of this
kind is also used for the purpose of administering pneumatic medicines.
Gelatine. A chemical term for animal jelly. It exists particularly in the ten-
dons and the skin of animals.

Whiten. A vegetable substance somewhat similar to animal eelatine. It is
the gluten of wheat flour which gives it the prope.-iy of^ making good
bread, and adhesive paste. Other grain contains a much less quantity of
this nutritious substance.
<rrain. The smallest weight made use of by chemical writers. Twenty grains
snake a scruple: 3 scruples a drachm ; 8 drachms, or 480 grains make an
ounce ; 12 ounces, or 5760 grains, a pound troy. The avoirdupois ^ound
contains 7000 grains.

Granulation. The operation of pouring a melled metal into water, in order
to divide it into small particles for chemical purposes. Tin is thus granu-
lated by. the dyers before it is dissolved in the proper acid.
"Gravity f specific. This differs from absolute gravity in as much as it is the
weight of a given measure of any solid or fluid body, compared with the
same measure of distilled water. It is generally expressed by decimals.
'Gums. Mucilaginous exudations from certain trees. Gum consists of lime,
carbon, oxygen, hydrogen, and nitrogen, with a little phosphoric acid.

Heat^ matter of. See Caloric.

Jlermetically. A term applied to the closing of the orifice of a glass tuT)e, «o
as to render it air-tight. Hermes, or Mercury, was formerly supposed to
have been the inventor of Chemistry ; hence a tube which was closed for
chemical purposes, was said to be Hermetically or chemically sealed. It
is usually done by melting the end of the tube by means of a blowpipe.

Hydrogen. A simple substance ; one of the constituent parts of water.

gas. Solid hydrogen united with a large portion of caloric. It is

•the lightest of all the known gases. Hence it is used to inflate ballooasi
It was formerly callec| inflammable air.

Hydro-Carbonates Combinations of carbon with hydrogen are described by
this term. Hydro-carbonute gas is procured from moistened charcoal by-

Bydrogenized mlphyrets. Certain bases combined with siflphurcttcd liydp©-

Hydro-Oxidet. MeUllio oxides combined vith^gfyj,yGoOQle

or cacMiejL hbrms.

Mfydrometeff^. fostniments for aeeertainisg the ipeeiflv gravity of spirilOttf

lioaors or other fltrids.
JBy^ometert. Instnimeuts for aseertaioing the degree of meiBtot^ in at-

mospherie air.
Hyfcroxyffenixed. A terra afpplied to subttancet which are combined with

the largc^ possible qiiafiti^ oif oxygen. We have muriatio acid, oxygoDi-

zed muriatic acid, and hyperoxygenized muriatic acid. The latter can

be exhibited only in combination.

I. *

J^/iamnaiion. A pheViomenon which takes place on mixing certain sub-
stances. The mixture of oil of turpentine with strong nitrous acid is an
instance of this peculiar chemical enect

Infuuon, A,8imple operation to procure the salts, juices, and other Tirtoes
of vegetables by means of water.

Intermediates. A term made use of when speaking of chemical aflSoity. Oil ,
for example, has no affinity for water, unless it be previously combined
with an alkali , it then becomes soap, and the alkali is said to be the tn^er-
mcdinm which occasions the union.

K. ' .

JOaH, A genus of marine plants which is burnt to procure minerkl alkal i
by afterwards lixiviating the ashes.


Jjoboratory, A room fitted up with apparatus for the performance of chem-
ical operations.

Jj€iciate8, Salts formed by the combination of any base with lactic acid.

Ixikeft. Certain colours made by combining the colouring matter of cochineal
or of certain vegetables, with pure aluniine, on with oxide of tin, zinc, &c,

Xofnp, Argand'i. A kind of lamp much used for chemical experiments. It
is made on the principle of a wind furnace, and thus produces a great de-
gree of light and heat without smoked

.Zieni. A glass, convex #i both sides, for concentrating the rays of the tan.
It is employed by chemists in fusing rcfractorjr snbstances which eaniMt
be operated on by an ordinary degree of heat.

Xtevigation. The grinding down of hard substances to an impalpable pow-
der on a stone with a Muller, or in a mill adapted to the purpose.

UUharge. An oxide of lead which appears in a state of vitrification. It is
formed in Uie process dT separating silver from lead.

Lixiviation, The solution of an alkali or a salt in water, or in some other
fluid, in order to form a lixivium.

Lixivium. A fluid impregnated with an alkaM or with a salt.

Lute, A composition foreclosing. the junctures of chemical vessels to pre-
vent the escape of gas or vapoiir>in distillation.


Mitcer^on. The steeping of a 'Sdlid body in a fluid, in order to soften it,

without iropregnating'the fluid.
Malates. Salts formed by the oombination'of any base with malic icid.
MaUeability. That property of mctats which gives them the capacity of

being extended and flattened by hammering. It is probably occasioned

by latent caloric.
Mauicot, A name ^ven to the yeilov oxide of lead, as minium is api)lte«1

10 the rsif oxide.
Matratt. Another name for a bolt-head.
Mnutnmm, The'floid in which a »ofiJ body is dissolved. Thus water is a

menstruum for salts, gums. Sec. and spirit of wine for resins.
Metallic Oxide9. Metals combined with oxygen. By this process they are

generally reduced lo a pulverulent form ; are changed fi-om combustible to

incombustible substances ; and receive the p»i»erty of beinir soluble in
. acids.
Mnerai, Any natural substance of a metallic, eartljy, or saline nature

•whether siooiile or compound, is deemed a- mineral:

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•MineraUxen, Those sobstanees which are oombined .vilh metabin Uieir
ores ; such are sulphur, arsenic, oxygen, cai'bonic aeid, ke.

Mneralogv. The science of fossils and roioerals. %

Mineral Watera. Waters which hoUl ^me meul, earth, or salt, in adla-
iioo. They are frequently termed Medicinal Waters.

Molybdiate: Salts formed by the combination of any base with the moiyb-

Mordants. Substances which have a chemical affinity for particular col-
ours; they are employed by dversas a bond to unite the colour with the
cloth intended to be dyed. Alum is of this cImss.

JduciUi^e. A glutinous matter obtained from vegetables, transparent and
^steless, soluble in water, but not in spidt of wine. It chiefly consists of

, xarbon and hydrogen, with a little oxygen.

•MunlteB. Salts fornieil by the combination of any base with the mucous acid.

Muffle. A semi-cylRidrical utensil, resembling the tilt of a boat, made of
baked clay ; its use is that of a cover to cupels in the assay furnace, to
. prevent the charcoal from falling upon the metal, or whatever is the sub*
ject of experiment

•Mwiates. Salts formed by the combination of any base with muriatic acid.

. * N.

Matron. One of the names for mineral alkali, or soda.

Jfeutralize. When two or more substances mutually di^ise each other's

properties, they are said to neutralize one another.
^utraX Salt. A substance formed h\ the union of an acid with an alkali,
- an earth, or a metallic oxide, in such proportions as to saturate both the

base and the i cid.
^trates. Salts formed by the combination of any base with nitric acid.
*JVitro^^en. A simple substance, by the French chemists called azote. It

enters into a variety of compounds, and forms more than three .parts in

four of atmospheric air. O.

Akhrea. Various combinations of the earths with uplde, or carbonate of iron.
■Ores. Metallic earths, which frequently contaiiTseveral extraneous mat*

ters ; such as sulphur, ai*senic, &c, ^
Oxaiatee. Salts formed by the combination of any base with oxalic acUl.
'Oxide. Any substan6e'combined with oxygen, in a proportion not sufficient

to produce acidity.
Oxidize. To combine ox};gen with a body without producing acidi^r.
-Oxidizement The operation by which any substance is combined with oi-

ygen, in a degree not sufficient to produce acidity.
^<kcygen. A simple subsunce composing the gi^eatest part of water, and

part of atmospheric air.

ffa». Oxygen coivvortetl to a ^;a8cous state liy calorie. It is also

called vital air. It forms nearly one tour^h of atmospheric air.
Oxtfg-enixe. I'o acidify a subsunce by oxygen. Synonymous with ozjgen<»

ate ; but the former is the better term. 1

Oxy^rdzemenU The production of acidity by Oxygen.

"* • -*

P^Hcle. A thin skin which forms on the surfiice of salineaolntioDS and oth-
er liquors, when boiled down to a certain strength.
JPhloffiaton. An old chemical name for an imaginary sobatanee, supposed to

be a combination of fire with some other matter, and a constftuentpart of

all inflammable bodies, and of many other substances.
/nosphates.- Salu formed by the oombinatkm of any base withphMphorie

^Phosphites. Suits formed by the combination of any base with phosphorQas

Phosphurets. Substances formed by an onion^with phosphorus. Thos we

have pliosphuret of lime, phosphuretted hydrogen, &c.
Plumbago. Carburet of iron, or the iblatklead-oX wmmeret.
Pneumatic. Any thing relatrnj^ to t*ie airs and gasses.
trjygh. A vessel filled in part with water or mercury, for the pw^


pose-of •colteetmg gases, to that tliey may be readily remoTed from Me
vessel lo another.

Precipitate, An) matter which, having been dissolved in a fluid, falls to
the bottom of the vessel, on the addition of some other substance capable
of producing a decomposition of the compound, in consequenceof^its at-
traction either for the menstruum or for the matter which was before
held in solution.

Precipitation That chemical process by which bodies dissolved, mixed,
or suspended in a fluid, are separated from that fluid, and made 4s gravi-
tate to the bottom of the vessel.

PrusHaies, Salts formed by the cdmbination of any base with prussic acid.

Putrefaction. The last fermentative process of nature, by which organized
bo<lies are decompesed so as lo separate their principles, for the purpose
of reuniting them by future attractions, in the production of new compo-

Pyrites, An abundant mineral fo«md on the English coasts, and elsewhere.
Some ai'e sulphnrets of iron, and othera sulphurets of copper, with a por-
taoa»of alumine and «ilex. The former are worked for the sake of the suU
phur, and the lattet* for sulphur and copper. They are also called Mar-
casites and Fire-stone.

■ - ■- martial. That species of pyrites whie^^ntains iron for its 1>a8is.
See a full account of these minerals in Henckll*« Pyritologia.

Pyrometer. An instrument invented by Mr. Wedgwood for ascertaining
the degrees of heat in fumacee andintense fires. See Philosophical -tran-
sactions, «rol. Jxii. and Ixiv. and Chemical Caiecb.

Pyrophori. Ck>mpound substances whieh heat of themselves, and tak^ fire oa
the admission of atmospheric air. See an account of a variety of experi-
ments with these compositions in Wiegleb^s Chemistry, quarto, p. Q^lQ^-kc.


Qttartz. A name given to a variety of silieeous earths, mixed with a small
portion of lime or alumine. Mr. Kirwan confines the term to the purer
kind of silex. Ruck cr^'stal and the amethyst are species of quartz.


Jiadhala. A chemical term for the Elements of bodies ; which see.

— — cofhpotmd. When the base of an acid is composed of two or more
substances, it is said that the acid is formed of a compound radical. THe
iulphurio acid is formed with a simple radical ; but the vegetable acids,
^hich haire radicals oon\posed of hydrogen -and carbon, are said to be aeidt
with compound radicals.

Reagents. ' Substance^whicli are added to mineral waters or other liquids
as tests to discover their nature and composition.

Meeeiv&rs. Globular ^lass vessels adapted to retorts for the purpose of pre-
serving and condensing the volatile matter raised in distillation.

FtecHficaiionfis nothing more'than the re-distillingaliquid to render It more
pure, or more concentrated, by abstraetine a part Of it only.

Reduction . The restoration of metallic oxides to their original state of me-
tals ; which is usually effected "by means ot charcoail and fluxes.

Refining. The process of separating the peifeet melals from other metallit
stJbAknces by what is called oupdiation.

ReJrigea*atoiry. A contrivance of any kind, swhidi, by containing cold water,
answers .the purpose of icondensing the ?ri^our or gas that arises'm distil-
lation. X worm-tub is a refrigeratory.

Reguhts. In its chemical acceptation, signifies a pure laetallie substance,
treed from all extraneous matters.

Reptilsion. A principle whereby the particles of bodies are prevented from
coming in actual contact. It is thought to be owing to caloric, which has
been called the repulsive power.

Resins. Vegetable juices concreted by evaporation either spontaneously or
by fire. Their character is solubility in alcohol, and not in water. It seems
that they owe their solidity chiefly to their union with oxygen.

Metort. A vessel in the shape of a pear, with its neck beat £>wnwards, vat


4*d in dMnatkm ; (he extretnitj of whick neek filt idto thit flf anotber

bottle called a receiver.
Jioek-crysttU: Cryttalliaed silez. S«

Saecholate9. Salts formed by the combination of anj bate with atecbolae*

tie acid.

SaUfiable batet. All the metals, alkali<>8, and earths, which are aapable of

eombining with acids, and forming salts, are called salifiable bases.
Saline. Partaking of the nroperties of salt
StUit, neutral A 'class or substances formed hy (he combination to satora*'

tion of an acid with an alkali, an earth, or other salifiable base.
.1 triple. Sal:s formed by the combination of an acid with two bases or

•Iradicals. The tartrate of soda and potass (Roehelle salt) is an insUnce

of.thiskind of comli^ination.
Saponaceout. A term applied to any substance which is of the nature or

-appearance of soap.
Saitwration. The act of Impregnating alBoid with another substance, till no

more can be received or imbibed. A fluid which hoMs as much of any

^aobsUnce as it can dissolve, is said to be saturated with that substance.

A solid maT in the same way be saturated with a fluid.
Sehatee. 9alts forced by the combination'Of any base with sebacic aaid.
S^ndMetaL A name »nerly given to those metals, which, if exposed to

the fire, are neither malteable, ductile, ilor fixed. It is a term not naed

br modem chemists.
SiUeeem Eatthe. A term used to describe a variety of natunil subatanees

which are composed chiefiy of silex; as quarti,ilint, sand, kc.
SSmpie Subttancee. Synonymous with Ekmenit / which see.
SmelHng'. The operation of fusing ores fbr the purpose of separating the

metals they contain, fVom the sulphur and arsenic with whioh they are

mineralized, and also from other heterogeneourmatter.
'-Mutton, The perfect union of a solid sufaatance with a fluid. Salu disaolr.^

ed in water are proper examples of s^ution.
Spare. A name formerlygiven to various crystallized stones;, such as the

fluor spar, the adamantine spar, &e. These natural substances are now

distinguished by names ^hich denote the nature of each.
SudacUtee, Certain coooi«tio|is of calcaifeons earth found suspended like id*

eles in caverns. They are formed liy the ooxing of water through the

ereviees, charged with this kind of earth.
Steatites. A kind of stone composed of silex, iron, and magnesia. Also

called French chslk, Spanish chalk, and soap-rock.
Sub'SaUe. Salts with *4ess acid than itf'sufficient to neutralize their radicals.
^uberatee. Salts formed by the combination of any base with the suberieaeid.
Sublimation. A process whereby certain volatile substances are raised by

heat, and again condensed by cold into a solid form. Flowers of sdtphar

are made in this way. The soQt of our common fires is a familiar In*

stance of this process.
Succinatee Salts formed br&e contbination of any base with the succinic aeid
Sulphates. Salts formed by the combination of any base with th^ sulphuric

Sulphites. Saltsformed byHhe combination of any base with the sulphurous

Suljthurestinil Sulphurets. Combbation of alkalies, or metals with sulphur.
Sulphuretted. A substance is said to be sulphuretted when It is combined

with sulphur. Thus we may say sulphuretted hydrogen, &c.
Super^Satts. Salts with an excess of acid, as the su]^itartrate of potass.
Synthesis. When a body is examined by dividing it into its component parts,

it is called analysis ; but when we attempt to prove the nature of a sub>

stance by the union of its principles, the operation is called synthesis.


Tartrates, Salts formed by the combination of any base with the acid of tartar
Temperature. The absolute quantity of free calorie*which is attached iMUij
body occasions the dagrec of temperature of that body^ GoOqIc


Tut, Thnt part of a cupel which ia impregnated with litharge in the opera-

- tion of refining lead. It is also the name of whatever is employed in cnexD-
ical experiments to detect the several ingredients of any composition.

Test-Papers. Papers impregnated with certain chemical re-agents ; such as
litmus, turmeric, radish, &c. They are used to dip into fluids to ascertain
by a change of colours the presence of acids and alkalies.

Tkermometer. An instrument to show the relative heat of bodies. Fahren-
heit's thermometer is that chiefly used in England. Other thermometers
are used in different parts of Europe.

Tinctures. Solutions ofsubstances in spiritous menstrua.

Trituration. A chemical operation whereby substances are united by fric-
tion. Amalgams are made by this method.

Tubulated. Retorts which have a hole at the top for inserting the materials
to be operated upon without taking them out of the sand heat, are called
tubulated retortB.

Tungstates. Salts formed by the combination of any base with tungstic acid.

Vacuum. A space unoccupied by matter. The term is generally applied to
the exhaustion of atmospheric air by chemical or philosophical means.

Vapour. This term is usea by chemists to denote ^uch exhalations only as
can be condensed and rendered liquid aeain at the ordinary atmospheric
tertiperature, in opposition to those which 3Lrr* permanently elastic.

Vital Air. Oxygen gas. The umpyrial or, fire-air of Scheele, and the dephlo-
gisticated air of Priestly.

Vitrification. When certain mixtures of solid substances, such as stlez and
alkali, are* exposed to an intense beat, so as to be fused, and become glass
they are then said to he vkrified, or to have undergone vitrification. '

Vitriols. A class ofsubstances, either earthy or metallic, which are combi-
ned with the vitriolic acid. Thus there is vitriol of lime, vitriol of iron,
vitriol of copper, Slc. These salts are now called Sulphates, because th«
acid which forms them is called sulphuric acid.

Vitriolated , Tartar. The old name for sulphate of potass.

Volatife Alkali. Another name for ammonia.

Volaiile Salts. The commercial name for carbonate of ammonia.

Volatility. A property of some bodies which dis(>oses them to assume tbft
gaseous state. This property seems to be owing to their afllniiy for caloric.

Volume. A term made use of by modern chemists to express the space occu-
pied by gaseous or other bodies, t


Union, chemical. When a mere mixture of two or more substances is mada^
Ihey are said to be mechanically united ; but when each or either sub-
Stance forms a component part of the product, tlie substances have form-
ed a chemical union.


Water. The most common of all fluids, composed of 85 parts of oxygen,
and 15 pf hydrogen.

— — mineral. Waters which are impregnated with mineral and other sab-
stances are known by this appellation. These minerals are generally held
in solution by carbopic, sulphuric, or muriatic acid.

Way^ dry. A term used by chemical writers when treating of analysis or de-
composition. By decomposing in the dry way, is meant, by the agency of

Way^ humid. A.term used in the same manner as the foregoing, but expres-
sive of decomposition in a fluid state, or by means of vvater, and chemical
reagents, or tests.

Welding Heat. That degree of heat in which two pieces of iron or of plati-
na may be united by hammering.

Wolfram. An oth of tungsten containing also manganese and iron.

Worm Tub. A clyemical vessel with a pewter worm fixed in the inside, and
in .the iutermeiiiate ^ace filled with water. Its use is to cool liquors da-

, xii^ distilUtion.

Digitized byV^OOQlC

384 BXPskinn&Nts.

Wmi^'^9 apparatus. A contrivance rbj- distilling the mineral acids and other
gaseous substances with little loss ; being a train of receivers with safety-
pipeSf and connected together by tubes.


Z(^re. An oxide of cobalt, mixed with a portion of silicioBS matter. It is
^nported in this state from Saxony.

Zero. The point from which the scale of a thermometer is graduated. Thus
Celsius's and Reaumur's thermometers have their zero at the /reexing
point, while the thermometer of Fahrenheit has its zero at that point at
which it stands when immersed in a mixture of snow and common salt.


In making up the following list of experitnents, 1 have been care-
ful in general to select such as can be mnde with safety to the jonng
student ; where this is not the case the caution is mentioned. Most
of them require but very simple apparatus. Where any ex peri-
ineot illustrates the text, a reference is made to the page. Some
of them are original, others are borrowed. I bare not, hofrever,
deemed it necessary to cite authors.

1. To show that heat is not absorbed, but reflected by polished
metallic surfaces, hold a common new tin pan before the fire. The
pan will remain cold. See p. 41.

2. To show Ihe power of a black surface to absorb caloric,
smoke or paint a black spot of the size of a dollar on the bottom of
a tin pan, and hold it towards the fire. On touching this .spot, it
will be found hot, while the parts around it remain cold. See p.

3. To make the upper part of a vessel of water boil, while there
is a cake of ice at the bottom. Into a glass tube put ivater enough
to occupy two inches. Freeze this, soas not to burst the tube, with
a freezing mixture, or by exposure to cold in winter. Then fill the
tube nearly full of water, and wind a flannel cloth several times
around the part containing the ice, so that the heat of the band will
not melt it. Then hold the tube in an oblique direction over a
lamp, so as Ao heat the water an inch or two above the ice. The
water will soon begin to boil, and by raisins' the tube a yttle at a
time, it will boil almost to the surface of tne ice, without melting^
it. See p- 62.

4. To show that some of the metals conduct caloric better than
others, procure wires of the same size and length, of gold, silver,
copper, iron, zinc, tin. Sic, The wires may be 12 or 14 inches long.
Coat one end of each with bees wax. and put the other ends into a
vessel of hot water. The wax will meH first on the metal which ii
the best conductor, and the comparative conducting powers are cal-
culated by the difference of time between the melting of the wax
on each. See p. 51.

5. The conducting powers of difiereot substances in re^^ard toca-
Jorie, may be much more sensibly elucidated, by touching in cold
weafther, a metal-with one hand, and a piece of cork, wood, or cloth
with the other. Here the «ensatton of coM, to the band which
Ipudies the metjU, is owing io the power which alkmetah bftve of

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Bxrx^msNTs. 335

coodttctini^ offbeat, more rapidly than any other class of substan-
ces. See p. 49.

^» To show that evaporation carries off caloric, moisten the bulb
of a tbernioineter tube with eiher^ by means of a hair pencil. The.
mercury immediately begins to fall, and if the process be continu-
ed, may be brought down to the freezing point, even in warm

Online LibraryMrs. (Jane Haldimand) MarcetConversations on chemistry .. → online text (page 41 of 43)