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colour blue, though it occurs also white I t is peculiar to the primitive monntains, and grey ; some specimens are entirely where it occurs imbedded in talc slate, blue, others are only spotted, striped, or and mica slate, accompanied with grenafamed with it. Externally and internally tite. It is found in many parts of Europe. its lustre is shining aud splendent, and com. It is reckoned the link which connects talc pletely pearly. It occurs in wedge-shaped with actynolite and trenolite. concretions, which are often very promis. KYLLINGIA, in botany, a genus of the cuous, and then pass into large and coarse Triandria Monogynia class and order. Nagrained distinct concretions. It feels grea- tural order of Gramina. Cyperoideæ, Jus. sy; is easily frangible, and the specific gra- sieu. Essential character: ament ovate or vity is from 3.5 to 3.6. It is infusible be- oblong, imbricate; flowers with a bivalve fore the blow-pipe, and is found to con- calyx and corolla. There are seven spesist of

cies, natives of the East and West Indies. Silica ............

29. 2 Alumina ........................ 55. O Lime .............

2.25 · Magnesia ........................

2.0 Oxide of iron ................ . 6.65 Water and loss ............... 4. 9

100.00

T'Or 1, the eleventh letter and eighth moist, by drawing over it a kind of rake, us consonant of our alphabet. It is a with thongs fixed to it, from which it is semi-vowel, formed in the voice by inter afterwards scraped. When it is very good cepting the breath between the tip of the it is black, soft, and has a fragrant odour tongue and the fore-part of the palate, with and a bitterish taste. Water dissolves about. the mouth open.

a twelfth part of it, and the matter taken up There is something of aspiration in its possesses gummy properties. When dissound, and therefore the Welsh usually dou- tilled with water, a small quantity of vola. ble it, or add an h to it; as in llan, or lhan, tile oil arises. Alcohol may also be impreg. a temple.

nated with a taste and odour of labdanum. In English words of ope syllable, it is LABATIA, in botany, a genus of the usually doubled at the end ; as in all, wall, Tetrandria Monogynia class and order. mill, &c. but in words of more syllables Natural order of Guajacanæ, Jussieu. Esthan one, it is only single at the end; as in ' sential character: calyx four-leaved, ipfefortel, proportional, &c. It may be placed rior; corolla subcampanulate, four-cleft, after most of the consonants, as in blue, with two minute segments in the division of clear, flame, &c. but before none of them. the corolla ; capsule four-celled; seeds soliAs a numeral letter, L denotes 50; and tary. There are two species, viz. L. sessiliwith a dash over it, thus, L, 50,000. flora, which is a native of Hispaniola ; and L.

LA, in music, the syllable by which guianensis is a tree exceeding forty feet in Guido denotes the last sound of each hexa. height, and three in diameter; the bark is of chord : if it begins in C, it answers to our a russet colour; the wood is hard and white; A; if in G, to E; and if in F, to D. the largest leaves are eight inches in length,

LABDANUM, or LADANUM, is a resin and three in width; flowers axillary, or on obtained from the surface of the crystus the branches in pairs or threes, each on its creticus, a shrub which grows in Syria and pedicel; corolla greenish. It is called by the Grecian islands. It is collected while the natives of Guiapa, pourama pouteri,

LABEL, in heraldry, a fillet usually combination of substances, in the whole no placed in the middle along the chief of the larger than a pepper-corn before the blow. coat, without touching its extremities. Its pipe, the effects take place with rapidity, breadth ought to be a ninth part of the and many of them, such as the escape of chief. It is adorned with pendants; and gas by effervescence, the changes of colour, when there are above three of these, the and transparency by differences in the heat number must be specified in blazoning. applied, the manner of acquiring the solid This is a kind of addition to the arms of a state, &c. which cannot be seen in the fur. second brother, to distinguish him from the nace, are in the course of a few seconds first, and is esteemed the most honourable ' remarked and ascertained. The saving of of all differences.

time is also an object of leading importance. LABEL, in law, a narrow slip of parch. The same considerations are likewise appli-, ment hanging from a deed, writ, or other cable to processes of fusion, or other appliwriting, in order to hold the appending cations of heat in a small vessel, snch as a seal.

tobacco-pipe, placed in a common fire, LABEL of a circumferentor, a long thin urged by the bellows if necessary. Hamid brass ruler, with a sight at one end, and a operations may also be very advantageously centre hole at the other ; chiefly used with a conducted by single drops of liquid, and tangent line, to take altitudes.

small particles of solid bodies laid upon a LABIAL letters, those pronounced chiefly glass plate, or in the metallic spoon, and by means of the lips. See LETTER.

the lamp for distillations, and other works LABIATED flowers, monopetalous flow. even upon a scale of some magnitude, has ers, consisting of a narrow tube, with a long been a favourite instrument with che. wide mouth, divided into two or more lips. mists. These will come under our notice as See BOTANY

we proceed. LABORATORY. A laboratory pro. Under our article CHEMISTRY we have perly fitted up with apparatus, is essentially given a concise sketch or enumeration of necessary to a chemist whose objects lead the practical treatment of bodies, which him to make researches, experiments, and leads us to point out the instruments in this processes, upon all the different scales of place. operation. That great interest which the For the mechanical division of bodies it important science of chemistry has excited is requisite the chemist should have the in all ranks of men, within the last thirty usual instruments for cutting, breaking. years, has rendered it easy to procure very rasping, filing, or shaving. One or more complete sets of apparatus ; which at least mortars for pounding ; the best are made of in the metropolis may be collected in a hard pottery. A stone and muller for a short time, by those who like Boyle, Ca- levigating. A pair of rollers for laminating vendish, Lavoisier, and other great men, metals. A forge for many, or most of the are in possession of ample means. But on purposes in which the blast heat of a small the other hand, it is proper to remark, that fire is required; and various other tools and many of our greatest discoverers, such as implements, not peculiar to chemistry. Scheele, Priestley, Berthollet, Wollaston, Messrs. Aikin, in their Chemical Dicti. Dalton, Crawford, and a numerous set of onary, give the following list of implements eminent men, have from choice, or from mo- and materials; which, upon deliberato exa. tives of prudence, made use of very simple, mination, we highly approve : cheap, and small sized apparatus. It is up- A gazometer, with the connecting tubes, doubtedly true that many operations can blow pipe, &c. , only be performed upon a scale of consi- A bladder, or silk bag, with stop cock, derable magnitude, and that many facts of fitting the above. great value display themselves upon the A pneumatic water trough. extensive theatre of nature or in large ma- A copper still with worm tub, the still nufactories, which are either not seen, or fitting into the top of the Black's furnace, require uncommon discernment to per- A blow-pipe, with spoon, &c. ceive them in the contracted space, and Lamps--an Argand, and others of com. during the short time employed in the per mon construction, for oil and alcohol. formance of a philosophical experiment. An apparatus for drying precipitates by But it is no less true that experiments upon steam. a small scale do likewise possess their exclu- Scales and weights... sive advantages. During the fusion and Large and small iron stands for retorts, &c.

Sieves.

..Mortars one of hard steel, one of bell- Ditto rods, for stirring corrosive Ouids.

metal, and one or two of Wedgwood Several stone-ware jars, with tin covers, ware.

for holding salts, &c. A silver crucible and spatula.

Also the following sundries : A platina crucible and spatula.

Wira different sizes and kinds, diz. A jointed iron tube for conveying gases. iron, copper, brass, silver, and platina. The following articles in glass :

Gold, silver, and brass leaf-linfoil.

Wooden tripod stands for receivers, &c. Retorts of different sizes, plain and stop

Fire tongs-various shapes. pered, and long necked for gases.

Steel spatula and pallet knives. Receivers to fit the above, plain and

Iron ladles. stoppered, with or without an adopter.

Diamond for scratching glass. Plain jars for gases, different sizes.

Files—at, three-cornered, and rat-tailed. Lipped jars for mixtures, precipitates, &c.

Hammers. A graduated eudiometer jar.

A vice and anvil. Bell receivers, two or three sizes.

Pincers. Proof bottles.

Shears and scissars. Capsules, or small evaporating caps.

A magnet. Water glasses (such as are used at table) which are very convenient for gentle eva

Filtering paper. porations.

Corks. Florence flasks.

Bladders--spirit varnish-sponge-low Matrasses - two or three very small,

-linen-flannel. and others of common size, round and flat

Windsorand common brickstiles-sand bottomed.

Lutes of various kinds. Funnels-ribbed, and one plain with a

For more extensive and delicate revery long neck for charging retorts. Wine glasses_common or lipped

searches it is also necessary to have Watch glasses, for evaporating minute

aporating minute A mercurial pneumatic trough. quantities at a very gentle heat.

A mercurial gazometer. Common decanters.

A burning lens of considerable power. • A bottle for specific gravity of fluids.

An electrical apparatus. · Phials of all sizes, plain and with ground A Galvanic apparatus. stoppers.

A detonating jar. Plain glass tube of various thickness and A glass or silver alembic. bore, out of which may easily be made, The fuel to be employed has been already Syphon tubes,

mentioned under that article, and a supply Bent tubes for gases,

should be kept pear at hand, broken down Capillary tubes, for dropping liquids, ready for use.

and various other useful articles. With regard to the different substances A gas-saturating apparatus.

or re-agents to be kept, the chemist will, A Woulfe's apparatus.

of course, wish to have a specimen of all A tube of safety, separate.

the simple or individual substances, such as A barometer.

the acids, earths, metals, &c. but the simThermometers-common, and with the ple and compound substances which are of bulb naked, to dip into liqnors.

general use, ought also to stand on the

shelyes. The following in earthen ware.

For many purposes the ordinary degree Crucibles-Hessian, common, and black of purity in which these substances are lead, of different sizes and shapes, with obtained by the common processes are stands and covers.

sufficient; so, for example, the small quanRetorts.

tity of potash in common sulphuric acid, Retort stands.

and of iron in common muriatic acid, selCapels.

dom interferes with any of the uses to Wedgwood evaporating dishes-a set. which those re-agents are applied; but it is White basons, with lips, different sizes. also necessary frequently to have them in Common white cups and saucers.

the utmost purity when employed as tests Tabes-straight and bent.

for delicate purposes. The chemist will Porcelain spoons.

therefore find it of advantage to reserve 4

Mercury.

separate set of a few of the most necessary Plaster of Paris. - Te-agents in their utmost purity, and if only White marble.

employed when absolutely required, a very, Bone-ash. moderate quantity will suffice. In the sub- Fluor Spar. : joined list we have distinguished by the Potash, pure. S. word pure thuse substances which require

- common caustic. S. particular pains to be obtained absolutely Pearl-ash. D. and S.. pure. Mixtures of each of the stronger Salt of Tartar. D. and S. acids and water in two or three different Super-carbonate of Potash. D. and known proportions shonld also be kept. Carbonate of Soda. D. and S. · N. B. The letter D implies that the dry

fully dried, substance should be kept, and S, that it .Ammonia, pure... should be in solution.

Carbonate of Ammonia. D. and 8. Sulphuric acid, pure.

.. . Super-carbonate of ditto. D. - common.

Lime, Nitric acid, pure and boiled.

Lime-water. common and boiled,

Barytic-water. - fuming.

Strontian-water. Muriatic acid, pure.

Carbonate of Magnesia - cominon.

Hydro-sulphureted water.
: Oxymuriatic acid. This should be kept Hydro-sulphuret of Soda. S.
in the dark.

Ammonia. S.
Phosphoric acid, pure, from phosphorus S. Sulphuret of Potash. D.
Acetic acid.

White Arsenic. D. and S. • Distilled vinegar.

Manganese, black oxide of. - constrated by frost. Oxalic acid. S.

red oxide of. Tartareous acid. S.

Nitrate of Mercury. S. Sulphate of Potash. D. and S..

Corrosive muriate of ditto. D. and S. - Soda. D. and S.

Zinc, in sticks and granulated. - Barytes. D.

Tin. - Alumina. S.

Muriate of Tin. -- Strontian. D.

Lead. Alam. D. and S.

Minium and Litharge.
Nitrate of Potash. D. and S.

Nitrate of Lead. S.
Ammonia. D.

Acetite of ditto. S.
Barytes. S. ,

Iron, filings, turnings, wire.
- Strontian. S.

Sulphnret of Iron for sulphuretted bydroMuriate of Soda. D. and S.

gen gas. - Ammonia. D. and S.

Sulphate of Iron. D. and S. - Strontian. S.

- saturated with nitronis

Barytes. S. A
Lime. D. and S.

Muriate of Iron.
Alumina. S.

Copper, sheet, wire. in • Oxymuriate of Potash. D.

Nitrate of Copper: D. and S. Phosphate of Soda. D. and S.

in Silver, leaf and wire. Ammonia. D.

Nitrate of Silver. S.
Acetite of Barytes. S.

Sulphate of ditto, S.
Alumina. S.

Acetite of ditto. S.
Oxalate of Ammonia. S.!

Gold-leaf. Cream of Tartar. D.

Nitro-muriate of Gold. :: Crude Tartar. D.

- Platina. Tincture of Galls.

Sulphur. Borax. D. and S.

Phosphorus. - vitrified.

Alcohol, concentrated and common. Fluate of Ammonia. S..*".

Sulpburic ether. Succinate of Ammonia. 8.

Litmus Tincture. · Prussiate of Potash, pure and dry. This: Turmeric. shonld be kept in the dark. noi.

Brazil wood. Prussiate of Lime. S... ,'. ; . Gall-out,

gas.

PI

Catechu,

neck. Generally speaking, this is not a Isinglass.

very useful instrument. In large distillaOlive oil.

tions an alembic or still is used, but the Lipseed-oil, drying.

condensation is effected by a spiral pipe, Oil of Turpentine..

called the worm, which passes through a Black flux.

tub of cold water. In the use of the alemDistilled water, in great plenty.

bic, fig. 2, the beak is inserted into a reThe most convenient arrangement for a

ceiver. When the volatile product of a laboratory where space is not wanted, body exposed

body exposed to be dried, or to undergo seems to be that of two rooms, and a slied evaporation by heat, is not required to be or apartment which can be thrown open to preserved, the process is performed in an communicate with the air. The first may contain the books of register, of practical

The application of heat to vessels is made reference, together with the more delicate either by naked fire, or by the intervention philosophical and chemical instruments, of some heated substance, which is then products, and preparations. The second called a bath. Chemical baths are made of may be provided with the work-bench, sand, or of melted lead, or the fusible metal, hammers, anvil, vice, and other tools, and or of brine, and very frequently of water. the different furnaces; and the shed may The evaporable liquids form a bath which be devoted to experiments of danger, such cannot be heated beyond their respective as arise from explosions, noxious vapours, boiling points; and the other baths, the and the breaking of vessels. It will be most common of which is that of sand, are most convenient that these should be upon chiefly valuable for giving a regular heat the ground floor, to secure the advantage without sudden changes, of a ready supply of water or fuel, and This last purpose is effected likewise other articles of heavy consumption. The with glass vessels, by coating them with a first of which articles may be largely want- lute, ed, in case of accidental combustion, as wellA very great number of furnaces have as on common occasions. But it is likewise been constructed for chemical and manunecessary that the place should be dry, in facturing purposes, for which we must neorder that labels may be preserved, and cessarily refer to the extensive works ap. other inconveniences avoided. This is the propriated to these objects, The operative principal general argument, in favour of a chemist may have occasion for them of dif. laboratory above the ground floor.

ferent sizes and figures. A great deal may · It would carry as too far beyond the li-, be done with the common German stove, mits of our work if we were to give draw. and with small furnaces made out of blackings and descriptions of the great variety of lead pots, But, in general, the philosophivessels, furnaces, and apparatus, which cal chemist will be well accommodaled have been contrived for general and parti. with one good furnace, convertible to dif. cular purposes of chemistry; and many of ferent uses; and out of many such we the culinary and domestic vessels may also select that of Dr, Black, for its simplicity be applied in experimental chemistry. We and efficacy, as described in his lectures. shall therefore confine ourselves to a few P late-iron is by far the best material for of the most simple and useful.

the ontside of an experimental furnace: but, In Plate Laboratory, fig. 1, represents as its metal communicates heat very fast, this a retort, a, and receiver, b. These ves. must be cut off by a proper lute lining. sels are used for distillation. The sub. The Doctor so far succeeded in this respect, ject is pat into the belly of the retort, a, that his furnace, though only two inches and exposed to heat, and the volatile pro- thick in the middle, will vot scorch paper ducts pass over into the receiver, b, which applied to its outside, when it is melting may be kept cool by the application of wet iron within. He adopted the simplest reccloths, or by immersion in cold water, or tilineal shapes, because workmen find great otherwise, if needful. The place of judc. difficulty in executing curved and uncom. tion is secured either by fitting the necks mon forms; and not one of a score of them together by grinding, or by means of a luie, will do it with accuracy. Indeed, those which see farther on. At ¢, in the receiver, bighly praised forms seemed to him of very is a neck closed by a stopper, Receivers or little importance in most cases. retorts, with this additional neck, are said The body, or fire-place, is the only part to be tubulated. Fig. 2, is an alcmbic, of of this furnace that requires description; which a is the body, b the bead, and c the the ash pit, with its door and registers and

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