Cooley's Cyclopaedia of Practical Receipts Volume I Part 150

When the aqueous solution of citric acid obtained, as already described, is concentrated by boiling in an open evaporating pan, the acid is not only liable to suffer partial decomposition by its long exposure to the air, but it not unfrequently acquires a brown colour from the carbonisation those portions of the liquid undergo which are in contact with the bottom of the pan, which being heated by high-pressure steam frequently reaches a temperature exceeding 200 F. This latter result is brought about in consequence of the slight movement in the dense acid liquor in the pan. To remedy the loss and inconvenience arising from the employment of the open evaporating pan, some years back Mr Pontifex devised an apparatus which effects the evaporation of acid liquor _in vacuo_ (and therefore out of contact with air), and at a temperature never exceeding 130 F. Moreover, in Mr Pontifex's boiler the time necessary for the concentration of the citric-acid liquor is diminished to about an eighth, and as the strong ebullition keeps the liquid in constant motion its charring is entirely prevented.

Mr Row says that lemon juice may be purified to a great extent by diluting it with water until it contains about 12 oz. of acid to the gallon, and then filtering from the flocculent precipitate of mucilage thus thrown down. The citrate of lime obtained from juice so treated is comparatively pure.

Good lemon juice yields about 6-1/2% of crystallised lemon acid; 2 galls.

yield fully 1 lb. of crystals. See LEMON JUICE, LIME JUICE. &c.

=CIT'RON.= The fruit of the citron tree (_Citrus medica_) is acidulous, antiseptic, and antis...o...b..tic; it excites the appet.i.te, and stops vomiting; and, like lemon juice, has been greatly extolled in chronic rheumatism, gout, and scurvy. Mixed with cordials, it is used as an antidote to the manchineel poison.

=Citron, Oil of.= See OIL.

=Citron Peel.= This is prepared in the same way as candied orange and lemon peel, which it for the most part resembles.

=Citron.= _Syn._ LEM'ON COLOUR. The term applied to a pale and delicate shade of yellow. See YELLOW DYES, &c.

=CIT'RONELLE.= See LIQUEURS and OILS (Lemon-gra.s.s).

=CITRUS.= A genus of plants belonging to the natural order _Aurantiaceae_, the species of which yields useful fruits. From _Citrus Aurantium_, and its varieties, all the various descriptions of sweet oranges are obtained.

The species _C. Bigaradia_ or _vulgaris_ yields the bitter or Seville orange; _C. Limonum_ and its varieties, yield the lemons; _C. Limetta_ is the source of the lime; _C. medica_ of the citron; _C. Dec.u.mana_ of the shaddock; _C. paradisi_ of the forbidden fruit; _C. Pampelmos_ of the Pampelmoose; and _C. j.a.ponica_ of the k.u.mquat.

=Citrus Bergamia.= (Ind. Ph.) _Syn._ THE LIME TREE. _Habitat._ Commonly cultivated in India and other tropical countries.--_Officinal part._ The fruit (lime) closely resembles the lemon, but is smaller, with a smoother, thinner rind, and of somewhat less fragrant odour. Its juice (lime juice) has the same pungent acid taste, and contains the same ingredients as lemon juice, though in somewhat different proportions, that of the citric acid being larger and that of the mucilage less in quant.i.ty. Much of the article imported into England under the name of lemon juice is obtained from the lime.--_Properties and Uses._ Very similar to those of the lemon, the juice being equally refrigerant and antis...o...b..tic; indeed, it is preferred by many tropical pract.i.tioners.

The fresh juice of the lime is procurable in almost every portion of the tropics, and is considered more effectual than preserved lemon juice.

Lime juice may be advantageously employed in the manufacture of citric acid, the proportion of this acid being larger than in lemon juice.

=CIV'ET.= _Syn._ CIVET'TA ZYBETH'UM, L. A perfume obtained from the civet cat (_Viverra civella_, Linn.), a fierce, carnivorous quadruped, somewhat resembling a fox, found in China and the East and West Indies. The civet is secreted in a sort of pouch between the a.n.u.s and the s.e.xual organs.

"Several of these animals have been brought into Holland, and afford a considerable branch of commerce, especially at Amsterdam. The civet is squeezed out in summer every other day, in winter twice a week; the quant.i.ty procured at once is from 2 scruples to 1 drachm or more."

Civet is frequently adulterated with spermaceti and b.u.t.ter, and a similar substance to civet, but of a darker colour, obtained from the polecat.

When pure it has an odour intermediate between that of musk and ambergris, but less refined; a pale-yellow colour; an acrid taste; and the consistence of honey. It is used in perfumery.

=CLAIRET.= See LIQUEUR.

=CLAR'ET RAGS.= _Syn._ TOURNESOL EN DRAPEAU, Fr.; BEZET'TA CRU'LEA, L. 1.

Pieces of clean linen coloured with Auvergne--or ground archil.

2. Pieces of linen dipped into the juice of mulberries, blood-red grapes, lees of red wine, &c. Used to colour jellies, confectionery, the rind of cheeses, &c.

=CLARIFICATION.= The act of clearing or making bright; commonly applied to the process of 'clearing' or 'fining' the liquids by chemical means, instead of by filtration. The substances used for this purpose are popularly known as 'clarifiers' or 'finings.'

The substances employed in the clarification of liquids operate by either mechanically embracing the feculous matter, and subsiding with it to the bottom of the vessel, or by inducing such a change in its nature or bulk that it subsides by its own density, in each case leaving the liquor transparent. Alb.u.men, gelatin, the acids, certain salts, blood, lime, plaster of Paris, alum, heat, alcohol, &c., serve in many cases for this purpose. The first is used, under the form of white of egg, for the clarification of syrups, as it combines with the liquid when cold, but on the application of heat rapidly coagulates and rises to the surface, carrying the impurities with it, forming a sc.u.m which is easily removed with a skimmer. It is also much used for fining wines and liqueurs, particularly the red wines and more limpid cordials. Gelatin, under the form of isingla.s.s, dissolved in water or weak vinegar, is used to fine white wines, beer, cider, and similar liquors that contain a sufficient quant.i.ty of either spirit or astringency (tannin), to induce its precipitation. Sulphuric acid is frequently added to weak liquors for a similar purpose, either alone or after the addition of white of egg or gelatin, both of which it rapidly throws down in an insoluble form. A pernicious practice exists among some unprincipled manufacturers of using certain salts of lead and potash to clear their liquors; especially those that are expected to sparkle in the gla.s.s, as 'cordial gin,' &c. For this purpose a little sugar of lead, dissolved in water, is first mixed up with the fluid, and afterwards a little more than half its weight of sulphate of pota.s.sa, also dissolved in water, is added, and the liquor is again 'roused' up. By standing, the sulphate of lead, formed by this mixture, subsides, and leaves the liquor clear. Bullock's blood is used in the same way as isingla.s.s or white of eggs, for fining red wines, beer, and porter.

Lime, alum, alcohol, acids, and heat, act by curdling or coagulating the feculencies, and thus, by increasing their density, induce their subsidence. Plaster of Paris acts, partly like the above, and partly like alb.u.men, or gelatin, by developing and forcing down the suspended matter.

Sand is often sifted over liquors (especially cordials and syrups), for the simple purpose of acting by its gravity, but appears to be quite useless, as it sinks too rapidly. The juices of plants are clarified by heat, which coagulates the alb.u.men they contain. Marl or clay is frequently used to clear cider and perry. A strip of isingla.s.s is generally employed to clarify coffee. See WINE, BREWING, CORDIALS, COFFEE, FININGS, INFUSION, &c.

=CLAY.= Clay is formed from the disintegration of felspathic rocks, by the combined action of air and water. Its plasticity, when moist, and its capability of being made hard by heat, are properties which render it available for many useful purposes. The purest kind of clay is kaolin, or China clay, which consists almost entirely of silicate of aluminum. It is found in China; but a precisely similar substance is obtained from deposits in Cornwall and some parts of France. Pipe-clay, a white clay nearly free from iron, is found in large quant.i.ty in the island of Purbeck. Potter's clay is found in many parts of Britain; that of Devonshire and Dorsetshire is much valued. Brick clay contains varying proportions of iron; hence the different colours of the bricks used in different countries. See ALUMINUM, FULLER'S EARTH, OCHRE, &c.

=CLEAN'ING.= In domestic economy the best way to clean a house is to keep it clean by a daily attention to small things, and not allow it to get into such a state of dirtiness and disorder as to require great and periodical cleanings. Some mistresses, and also some servants, seem to have an idea that a house should undergo regular cleanings, or great washing and scrubbing matches, once every three or six months, on which occasions the house is turned almost inside out, and made most uncomfortable. All this is bad economy, and indicates general slovenliness of habits. (Chambers.) For hints upon cleaning, see CARPETS, CLOTHES, &c.

=CLEAN'LINESS.= See ABLUTION, BATHING, and SICKNESS.

=CLIPPING= (HORSES). Some horses should be worked in autumn in cloths, or with their coats on, as, on account of the extra sweating thus caused, they will be in better condition for the hunting season. Such horses should be clipped or shaved. The horse's coat should be fully set before it is clipped. Those horses which sweat much in autumn should be singed.

Singeing cannot be begun too early. The fresh growth must be removed every week. Singeing may be best accomplished by means of gas.

=CLOTHES.= Economy and cleanliness require due attention to be paid to every article of clothing, but more especially to those which are the most exposed to dirt and the weather. The following remarks, having reference chiefly to woollen articles, may prove useful to the reader:--If very dusty, hang them on a horse or line, and gently beat them with a cane; then lay them on a clean board or table and well brush them, first with a stiff brush, to remove the spots of mud and the coa.r.s.est of the dirt, and next with a softer one, to remove the dust and to lay the nap properly. If clothes are wet and spotted with dirt, dry them before brushing them, and then rub out spots with the hands. The hard brush should be used as little as possible, and then with a light hand, as it will, if roughly and constantly employed, soon render the cloth threadbare. Spots of tallow-grease on the clothes may be taken off with the nail, or, if that cannot be done, have a hot iron with some thick brown paper, lay the paper on the part where the grease is, then put the iron upon the spot; if the grease comes through the paper put on another piece, till it ceases to soil it. Moths may be prevented attacking clothes by putting a few cloves or allspice into the box or closet with them. See b.a.l.l.s, CLOTHES, and SCOURING, &c.

=CLO"THING.= In our changeable climate great care should be taken to clothe the body effectually; for when the skin is chilled the blood is determined in increased and injurious quant.i.ty to the internal organs, causing colds and inflammations. The ordinary materials for clothing are cotton, linen, woollen, and silk. Cotton is generally employed for undergarments, for which its softness and warmth render it well adapted.

Linen is not nearly so warm, but it keeps its colour better; it is more expensive, and although it wears much longer, it is not so economical as cotton. Woollen garments are, in cold and variable climates, almost essential to comfort; the warmth obtained by wearing flannel next the body is very beneficial, and the slight stimulating effect arising from its roughness tends to keep the skin in healthy action.

The practice of dressing infants in long clothes is a very objectionable one, for besides being injurious to health it cramps the action of the legs, the feet, and the toes, and by so doing prevents their proper and healthy development.

An infant should be so clothed as to combine sufficient warmth with perfect freedom of the limbs; hence his garments should be loose instead of tight, more particularly round his waist.

In the selection of winter clothes for children, if for in-door wear, choice should be made of a dark woollen frock, and of stockings in preference to socks. The stockings should be of merino, and made to draw above the knees and fastened to the dress with a loop and tape instead of garters, which are very objectionable.

A child's out-of-door attire in winter should additionally comprise a warm and properly-lined coat, made of cloth or some woollen fabric. It should b.u.t.ton close to the chin and cover his neck. Mr Chava.s.se says, for this latter purpose a woollen neckerchief or scarf is preferable to furs. It is very important that the child's feet and legs should be kept warm, but not too warm. In infancy and childhood--in summer as well as winter--the wearing of flannel next the skin is more necessary, and beneficial even, than when practised by adults.

=CLOVE.= _Syn._ CARYOPH'YLLUM (B. P.), L. The flower-buds of the _Ciryophyllus aromaticus_ (Linn.), or clove tree collected before they open, dried, and smoked. Cloves are aromatic, stimulant, carminative, and stomachic; and, according to some, possess febrifuge properties. They are chiefly used as an adjuvant in compound medicines. A few cloves kept in a closet or box prevent moths or mould attacking furs, woollens, &c.

It is a common practice to adulterate this spice in the same manner as cinchona bark. Cloves from which the oil has been distilled are dried and rubbed between the hands, previously moistened with a little sweet oil, to brighten their colour, after which they are mixed up with fresh spice for sale.

=Cloves, Mother of.= The unripe fruit of the clove tree; they are frequently imported preserved (preserved mother of cloves), and are reputed stomachic and antispasmodic.

=Cloves, Oil of.= _Syn._ O'LEUM CARYOPH'YLLI (B. P.), L. This possesses similar virtues to the unexpanded flower-buds, and is esteemed as a remedy for the tooth-ache. Used to flavour liqueurs and confectionery. Sp. gr.

1055-1060.

M. Jacquemin recommends the following as a very delicate test for the presence of carbolic acid when used as an adulterant for oil of cloves.

One drop of the suspected oil is mixed with a small trace of solution of aniline by means of a gla.s.s rod, and then shaken with 5 or 6 c. c. of distilled water. By the addition of a few drops of sodium hypochlorite to the mixture the characteristic blue coloration due to carbolic acid will be developed in a few minutes, whereas with the pure oil nothing but the purplish-violet colour of aniline will be perceived. Stirring or shaking must be avoided after the addition of the hypochlorite.

=CLYS'TERS.= See ENEMA.

=COAL.= The varieties of this valuable substance may be conveniently described under the three heads ANTHRACITE, LIGNITE, and PIT-COAL (which _see_). See also FUEL.

=COAL-TAR.= Coal-tar, one of the products of the destructive distillation of the coal employed in the manufacture of gas, is a very complex substance, consisting of various hydrocarbons, acids, and bases, together with certain resinoid and empyreumatic substances. The princ.i.p.al hydrocarbons yielded by coal-tar on distillation are: benzol, toluol, propyl, naphthalin, and anthracin; of these the first three are fluids, and the last two solids; the most important acids are: carbolic, cresylic, phlorylic, and nosolic; the chief bases are: aniline, chinoline, and lepidine. The quant.i.ty as well as the quality of the tar obtained from the distillation of coals varies considerably with the kind of coal used, as well as with the temperature at which the distillation is carried on, the yield of tar being smaller at very high temperatures than when lower ones are employed. Coal-tar, from its antiseptic properties (due chiefly to the carbolic acid it contains), is painted on wood to preserve the latter from decay when exposed to wind and weather. Mixed with coal-dust, saw-dust, and peat-dust, it forms a useful artificial fuel, and when incorporated with pebbles makes an excellent artificial asphalt for pavements. The chief value of coal-tar, however, consists in its being the source of those brilliant dye-stuffs, the coal-tar colours. These, together with the naphtha obtained from its distillation, have converted coal-tar from a worthless and unwelcome waste product of gas manufacture--for the removal of which from their premises the gas makers were formerly only too glad to pay--into a very considerable and important branch of profit and revenue.

The different const.i.tuents of the tar are separated from each other by distillation, the various products so obtained being further purified by various processes.

See TAR COLOURS, NAPHTHA, BENZOL, ANTHRACENE, &c.

=CO'BALT.= Co. _Syn._ REG'ULUS OF COBALT; COBALT'TUM, L. A metal discovered by Brandt, in 1733. It generally occurs in the same ore as nickel, and the separation of the two metals is a task requiring great patience and expertness. Speiss cobalt and cobalt glance are the ores from which the metal is commonly extracted.

_Prep._ 1. Dissolve oxide of cobalt in hydrochloric acid, and pa.s.s sulphuretted hydrogen gas through the solution, until all the a.r.s.enic is thrown down; filter, and boil with a little nitric acid, then add carbonate of pota.s.sium, in excess, and digest the precipitate in a solution of oxalic acid, to remove any oxide of iron; wash and dry the residuum (oxalate of cobalt), and expose it to great heat, in a covered crucible lined with charcoal; the product is pure metallic cobalt.

2. Mix equal parts of oxide of cobalt or roasted Cornish cobalt ore, and soft soap, and expose them to a violent heat in a covered crucible.

3. Pa.s.s hydrogen gas over oxide of cobalt strongly heated in a porcelain tube.

_Prop., Use, &c._ Cobalt is a white, brittle metal; unchanged in the air; feebly acted on by dilute hydrochloric and sulphuric acids; has a high melting-point, and is strongly magnetic; sp. gr. 85. It is seldom employed in the metallic state, from the great difficulty of reducing its ores, but its oxide (black oxide) is largely employed in the arts. It forms salts with the acids, which are interesting from the remarkable changes of colour which they exhibit. See INK, SMALTS, ZAFFRE, and _below_.

_Char., Tests._ Solutions of the salts of cobalt are known as follows:--1.