Chapter LIII: Part 2 (14)

DESICCATION or DRYING. In this way every article of food, both animal and vegetable, may be preserved without the application of salt or other foreign matter. The proper method is to expose the substances, cut into slices or small fragments, in the sun, or in a current of warm dry air, the temperature of which should be under 140° Fahr. Articles so treated, when immersed for a short time in cold water, to allow the albumen and organic fibres to swell, and then boiled in the same water, are nearly as nutritious as fresh meat cooked in the same manner. If a higher degree of heat than 140° be employed for animal substances, they become hard and insipid. Owing to the practical difficulties in the way of applying the above process to fresh meats, it is usually employed in conjunction with either salting or smoking, and, frequently, with both of them.

EXCLUSION OF ATMOSPHERIC AIR. This is effected by the method of preserving in sugar, potting in oil, and, more particularly, by some of the patented methods noticed below. Fresh meat may be preserved for some months in that state, by keeping it in water perfectly deprived of air. In practice some iron filings and sulphur may be placed at the bottom of the vessel, over which must be set the meat; over the whole is gently poured recently boiled water, and the vessel is at once closed, so as to exclude the external air.

IMMERSION IN ANTISEPTIC LIQUIDS. One of the commonest and most effective liquids employed for this purpose is alcohol of 60 to 70%, to which a little camphor, ammonia, sal ammoniac, or common salt, is occasionally added. A cheaper and equally efficient plan is to employ a weak spirit holding a little creasote in solution. A weak solution of sulphurous acid may be substituted for alcohol. Weak solutions of alum, or carbolic acid, with or without the addition of a few grains of corrosive sublimate, or of arsenious acid, are also highly antiseptic. These are chiefly employed for anatomical specimens, &c. A solution containing only 1/600th part of nitrate of silver is likewise very effective; but, from this salt being poisonous, it cannot be employed for preserving articles of food. Butchers’ meat is occasionally pickled in vinegar. By immersing it for 1 hour in water holding 1/400th part of creasote in solution, it may be preserved unchanged for some time even during summer.

INJECTION OF ANTISEPTIC LIQUIDS into the veins or arteries of the recently killed animal. It is found that the sooner this is done after the slaughter of the animal the more effective it becomes, as the absorbent power of the vessels rapidly decrease by age. See GANNAL’S PROCESS (_below_).

JERKING is a method of preserving flesh sometimes adopted in hot climates. It consists in cutting the lean parts of the meat into thin slices, and exposing these to the sunshine until quite dry and brittle, when they are bruised in a mortar, and pressed into pots.

PICKLING IN VINEGAR. In this method the substances, rendered as dry as possible by exposure to the air, are placed in glass or stoneware jars (not salt-glazed), or wooden vessels, when strong vinegar, either cold or boiling hot, is poured over them, and the vessel at once closely corked or otherwise covered up, and preserved in a cool situation. Meat is occasionally thus treated; vegetables frequently so. See PICKLE.

POTTING IN OIL. In this case salad or olive oil is substituted for vinegar (see _above_), and is always used cold.

SALTING acts chiefly by abstracting water from the albuminous portions of the meat, by which its disposition to change is lessened.

SMOKING. This process, which, as well as the last, is referred to further on, acts both by the abstraction of moisture and the antiseptic properties of certain substances (creasote, &c.) contained in wood smoke. Fresh meat and fish are occasionally smoked; but, in general, substances intended to be thus treated are first salted.

In Donkin and Gamble’s patent process the substances, previously parboiled, are placed in small tin cylinders, which are then filled up with rich soup; the lids are next soldered on quite air-tight, and a small hole is afterwards made in the centre; the cylinders are then placed in a bath of strong brine, or a strong solution of chloride of calcium, which is at once heated to the boiling point, to nearly complete the cooking process; after which the small hole in the lid is hermetically sealed by covering it with solder while the vessel still remains boiling hot; the tins are, lastly, again submitted to heat in the heated bath, the duration of which is proportioned to the quantity and character of their contents, the ‘dressing’ of which is to be perfected by this operation. The ends of the tins, on cooling, assume a concave form, from the pressure of the atmosphere, without which they cannot be air-tight, and the process has been unsuccessful. To determine this, the patentees expose the canisters, prepared as before, for at least a month in an apartment heated to about 100° Fahr.; when, if the process has failed, putrefaction commences, and the ends of the cases, instead of remaining concave, bulge or become convex. This is called the ‘test.’ By this process, which was invented by M. Appert in France about the year 1808, fish, flesh, poultry, and vegetables may be preserved for years in any climate.

Goldner’s process differs somewhat from the preceding, in the employment of a higher degree of heat, more hastily applied, and not prolonged or repeated after the tins are soldered up.

Gannal’s process, having for its object the preservation of butchers’ meat in the fresh state, depends on the peculiarly absorbent property of the flesh of recently killed animals, above referred to. This process consists in injecting a solution of sulphate of alumina, or, better, of chloride of aluminium, of the sp. gr. 1·070 to 1·085 (10° to 12° Baumé), into the carotid artery, by means of a syphon, as soon as the blood ceases to flow from the slaughtered animal; both extremities of the jugular vein being previously tied. 9 to 12 quarts of the solution are sufficient for an ox, and a proportionate quantity for smaller animals. A less quantity is also required in winter than summer. When the animal has been well bled, and the injection skilfully performed, it is scarcely perceptible that the animal has undergone any preparation. The injected animal is cut up in the usual way; and when intended to be eaten within 2 or 3 weeks merely requires to be hung up in a dry, airy situation free from flies; but if it is to be kept for a longer period, it is directed to be washed with a mixed solution of common salt and chloride of aluminium at 10° Baumé, and then simply dried and packed in clean air-tight barrels, and kept in a cool, dry place. If the air cannot be perfectly excluded, it should be packed in dry salt, not for the purpose of preserving it, but to prevent the vegetation of bissus, as, without this precaution, the meat becomes musty from exposure and the action of moisture. Meat preserved by this process may be kept for several years, and merely requires soaking for 24 hours in water, for the purpose of swelling its pores, to give it the appearance and taste of fresh meat, fit for either roasting or boiling. For hot climates a somewhat stronger solution, or a larger quantity of the usual one, may be injected. The use of the strong solutions ordered in some recent works, however, deprives the flesh of a portion of its apparent freshness, and makes it more nearly approach in flavour to that which has been slightly salted in the ordinary manner.

In addition to the above it may be added that both flesh and fish may be preserved by dipping them into, or brushing them over with, pyroligneous acid, and then drying them. This gives them a smoky flavour; but if pure acetic acid (Ph. L.) be used, no taste will be imparted. These fluids may be applied by means of a clean painter’s brush, or even a stiff feather. A table-spoonful is sufficient to brush over a large surface. Fish and flesh so prepared will bear a voyage to the East Indies and back, uninjured.

Fish may also be preserved in a dry state, and perfectly fresh, by means of sugar alone. Fresh fish may be thus kept for some days, so as to be as good when boiled as if just caught. If dried and kept free from mouldiness, there seems no limit to their preservation; and they are much more nutritious in this way than when salted. This process is particularly valuable in making what is called ‘kippered salmon,’ and the fish preserved in this manner are far superior in quality and flavour to those which are salted or smoked. A few tablespoonfuls of brown sugar are sufficient for a salmon of five or six pounds’ weight; and if salt be desired, a teaspoonful or two may be added. Saltpetre may be used instead of salt, if it be wished to make the kipper hard.

The well-known property possessed by ether, alcohol, pyroxylic spirit, chloroform, and certain other hydrocarbons, of averting putrefaction, has been thus applied by M. Robin:——He encloses the meat or other substances to be preserved in a glass case, along with a sponge or a capsule containing the preservative liquid, which latter is continually evolved in a vaporous condition, and exercises the preservative agency. In this way the vapours of hydrocyanic acid are found to be very efficacious. Camphor is thus employed in the MUMMY CASES in the British Museum.

It has been asserted by Mr George Hamilton that in an atmosphere of binoxide of nitrogen, in the dark, flesh preserves its natural colour and freshness for about five months; and eats well provided it be boiled in open vessels, to expel nitrous fumes. See CANDYING, EGG, FISH, FRUIT, MILK, PICKLES, POTTING, PRESERVES, SALTING, SMOKING, STUFFING, VEGETABLE SUBSTANCES, &c.

=PUT′TY.= This name is given to the following preparations (when used alone. ‘Glazier’s putty’ is generally indicated):——

=Putty, Glazier’s.= From whiting made into a stiff paste with drying oil. It is used to fix panes of glass in sashes, to fill holes and cracks in wood before painting it, &c.

=Putty, Plasterer’s.= A fine cement used by plasterers, made of lime only. It differs from ‘FINE STUFF’ in the absence of hair.

=Putty, Polisher’s.= _Syn._ PUTTY POWDER, CALCINE; CINERES STANNI, STANNI OXYDUM CRUDUM, L. A crude peroxide of tin, obtained by exposing metallic tin in a reverberatory furnace, and raking off the dross as it forms; this is afterwards calcined until it becomes whitish, and is then reduced to powder. Another method is to melt tin with rather more than an equal weight of lead, and then to rapidly raise the heat so as to render the mixed metal red hot, when the tin will be immediately flung out in the state of ‘putty’ or ‘peroxide.’ The products of both these processes are very hard, and are used for polishing glass and japan work, and to colour opaque white enamel. See TIN.

=Putty, To Soften.= Take 1 lb. of American pearlash and 3 lbs. of quick-lime. After slaking the lime in water add the pearlash, and let the mixture be made of a consistence about the same as that of paint. When required for use apply it to both sides of the glass, and let it remain in contact with the putty for twelve hours; after which the putty will have become so softened that the glass may be removed from the frame without any difficulty.

=PUZZOLA′NA.= PUOZZOLANA, or, more correctly, PUZZUOLANA, is a volcanic ash found at Puzzuoli, near Naples. When mixed with lime it forms an excellent hydraulic cement. A good FACTITIOUS PUZZOLANA may be made by heating a mixture of 3 bushels of clay and 1 bushel of fresh-slaked lime for some hours to redness. (M. Bruyere.) See CEMENT and MORTAR.

=PYRI′TES.= A term applied to several native metallic sulphides. IRON PYRITES is the best known of these.

=PY′RO-.= The term is applied to several acids that are obtained by the action of heat on other substances; as, PYROGALLIC ACID, PYROLIGNEOUS A., &c.

=PYROACE′TIC SPIRIT.= See SPIRIT (Pyroacetic).

=PYROGAL′LIC ACID.= HC_{6}H_{5}O_{3}. _Syn._ ACIDUM PYROGALLICUM, L. _Prep._ 1. From either gallic or tannic acid, heated in a retort by means of an oil bath, and steadily maintained at a temperature of about 420° Fahr. as long as crystals are formed in the neck of the retort, or in the receiver, both of which should be kept well cooled. Pure. If a much higher heat is employed, the product consists chiefly of metagallic acid.

2. From Aleppo galls, in very coarse powder, heated in a dish covered with thin filtering paper pasted to its edge, and connected with a well-cooled receiver. Dr Ure says that the so-called Chinese galls furnish, by dry distillation, a “very concentrated solution of pyrogallic acid, which, evaporated on the water bath, yields of brown crystalline pyrogallic acid nearly 15% of the weight of the galls.”

3. (Dr Stenhouse.) By sublimation from the dry aqueous extract of nut-galls, in a Mohr’s apparatus, in the same way that benzoic acid is obtained from benzoin resin, observing the precautions referred to in No. 1 (_above_). Nearly pure. The product is fully 10% of the weight of extract operated on.

_Prop._ Light crystals, which, when perfectly pure, are quite white; freely soluble in water, but the solution cannot be evaporated without turning black and suffering decomposition; it strikes a rich blackish-blue colour with the protosalts of iron, and reduces those of the sesquioxide to the state of protoxide; when heated to 480° Fahr., it is converted into METAGALLIC ACID and water.

_Uses, &c._ Pure pyrogallic acid is now very extensively employed in photography. A solution of the crude acid mixed with a little spirit is used to dye the hair, to which it imparts a fine brown colour, but has the disadvantage of also staining the skin when applied to it.

=PY′ROGEN ACIDS.= Those generated by heat.

=PYRO′LA.= See WINTER GREEN.

=PYROLIG′NEOUS ACID.= _Syn._ VINEGAR OF WOOD†, SPIRIT OF W.†, SMOKING LIQUOR†, ESSENCE OF SMOKE†; ACIDUM PYROLIGNOSUM, L. Impure acetic acid, obtained by the destructive distillation of wood in close vessels. It comes over along with tar creasote, and other liquid and gaseous matters. In this state it contains much empyreumatic matter in solution; but by separation from the tar, saturation with slaked lime or chalk, defecation, and evaporation, an impure acetate of pyrolignate of lime is obtained, which, after being gently heated, to destroy part of its empyreumatic matter, without injuring its acetic acid, is again dissolved and defecated, and then precipitated by a solution of sulphate of soda, when a solution of acetate of soda and a precipitate of sulphate of lime are formed by double decomposition. The solution is next evaporated to dryness, the dry mass (pyrolignite of soda) dissolved in water, and the new solution filtered and recrystallised. The crystals of acetate of soda, obtained by the last process, yield nearly pure acetic acid by distillation along with sulphuric acid. See ACETIC ACID and VINEGAR.

=PYROLIG′NEOUS SPIRIT.= See SPIRIT (Pyroxilic).

=PYROM′ETER.= An instrument to measure high degrees of heat. WEDGWOOD’S PYROMETER, the one best known, depends on the property which clay possesses of contracting when strongly heated. PROF DANIEL’S PYROMETER consists, essentially, of a small rod or bar of platinum, which acts in a precisely opposite manner to the preceding, viz., by its expansion.

=PYROPH′ORUS.= _Syn._ LUFT-ZUNDER, Ger. Any substance that inflames spontaneously when exposed to the air.

_Prep._ 1. Neutral chromate of lead, 6 parts; sulphur, 1 part; triturate them with water, q. s. to form a paste, and make this into pellets; dry these perfectly by a gentle heat, then heat them in a closed tube until the sulphur is all driven off; lastly, transfer them to a stoppered phial.

2. (HOMBERG’S PYROPHORUS.) From alum and brown sugar, equal parts; stir the mixture in an iron ladle over the fire until dry, then put it into an earthen or coated glass phial, and keep it at a red heat so long as the flame is emitted; it must then be carefully stopped up and cooled.

3. (Dr Hare.) Lampblack, 3 parts; burnt alum, 4 parts; carbonate of potassa, 8 parts; as the last.

4. (Gay Lussac.) From sulphate of potassa, 9 parts; calcined lampblack, 5 parts; as No. 2.

5. Alum, 3 parts; wheat flour, 1 part; as No. 2.

6. (LEAD PYROPHORUS——Göbel.) Heat tartrate of lead to redness in a glass tube, and then hermetically seal it. See TARTRATE OF LEAD.

_Obs._ When the above are properly prepared, a little of the powder rapidly becomes very hot, and inflames on exposure to the air. The accession of the combustion is promoted by moisture, as a damp atmosphere or the breath. With the exception of the first and sixth, “they owe their combustibility to the presence of sulphide of potassium.” (Gay Lussac.)

=PYROPHOSPHOR′IC ACID.= See DIBASIC PHOSPHORIC ACID (Phosphorus).

=PYRO′SIS.= _Syn._ BLACK WATER, WATER BRASH, WATER QUALM. An affection of the stomach, attended by a sensation of heat and the eructation of a thin, sour liquid, often in considerable quantity, especially in the morning.

The following pill will be found of service in this affection:——Powdered opium, 1/8th gr.; subnitrate of bismuth, 5 gr.; extract of gentian, sufficient to make into 2 pills. To be taken two or three times a day, before meals.

The solution of bismuth and citrate of ammonia (Liquor Bismuthi et Ammoniæ Citratis, B. P.), in doses of 1/2 dr. to 1 dr., taken as above, is another medicine which may be had recourse to, should the above fail to give relief.

=PYBOTARTAR′IC ACID.= H_{2}C_{5}H_{6}O_{4}. Obtained by the destructive distillation of tartaric acid. See TARTARIC ACID.

=PYROTECH′NY.= The art of making fireworks. The three principal materials employed in this art are charcoal, nitre, and sulphur, along with filings of iron, steel, copper, or zinc, or with resin, camphor, lycopodium, or other substances, to impart colour, or to modify the effect or the duration of the combustion. Gunpowder is used “either in grain, half crushed, or finely ground, for different purposes. The longer the iron filings are, the brighter red and white spots they give; those being preferred which are made with a coarse file, and quite free from rust. Steel filings and cast-iron borings contain carbon, and afford a more brilliant fire, with wavy radiations. Copper filings give a greenish tint to flame; those of zinc, a fine blue colour; the sulphide of antimony gives a less greenish blue than zinc, but with much smoke; amber affords a yellow fire, as well as colophony (resin) and common salt; but the last must be very dry. Lampblack produces a very red colour with gunpowder, and a pink one with nitre in excess; it serves for making golden showers.” When this substance is lightly mixed with gunpowder and put into cases, it throws out small stars resembling the rowel of a spur; this composition has hence been called ‘spur fire.’ “The yellow sand, or glistening mica, communicates to fire-works golden radiations. Verdigris imparts a pale green; sulphate of copper and sal ammoniac gives a palm-tree green. Camphor yields a very white flame and aromatic fumes, which masks the bad smell of other substances. Benzoin and storax are also used, on account of their agreeable odour. Lycopodium burns with a rose colour and a magnificent flame; but it is principally employed in theatres to represent lightning, or to charge the torch of a Fury.” (Ure.) See FIRES (Coloured), FLAME COLOURS, GUNPOWDER, STARS, ROCKETS, &c.

The following substances are in requisition by the Pyrotechnist:——

ZINC. This metal is employed in the form of fine powder, which is obtained as follows:——The metal, scarcely melted, is poured into a hot mortar, where it is reduced to powder, being kept during the operation at a temperature of 401° F. It is then sifted to remove any particles which may have escaped contact with the pestle.

COPPER. This metal may be obtained in a state of minute division by precipitating it from a solution of sulphate of copper by means of iron, the precaution being taken of using a large quantity of iron. The precipitate, after being well washed, is dried between folds of blotting paper, and kept in well stoppered bottles.

IRON-SAND. A quantity of sulphur is melted in a crucible over a slow fire, and when it is quite fluid, iron filings are thrown in while the whole is being stirred. The crucible is removed from the fire, and the contents are rapidly stirred until cold. The material is then rolled on a board till it is broken up as fine as corned powder, after which the sulphur is sifted out.

SODA POWDER. This powder is prepared with the same precaution as ordinary gunpowder, the proportions which answer best being:

Nitrate of soda 630 parts.
Sulphur 125 ”
Charcoal 125 ”
————
880 parts.

As the nitrate of soda is hygrometric, this powder must be preserved in closed vessels from the moisture of the air.

LEAD POWDER. This mixture is also prepared like gunpowder, and the constituents are used in the following proportions:

Nitrate of lead 12 parts.
Nitrate of potash 2 ”
Charcoal 3 ”
——
17 parts.

In the manufacture of this mixture on a large scale considerable care is necessary, since the mixture of nitrate of lead and charcoal is very liable to ignite by friction.

PREPARED BLOOD. 450 to 500 grammes of zinc is dissolved in 1340 grammes of hydrochloric acid 22° B., largely diluted with water, and filtered. This solution is again diluted with its own volume of water, and mixed with fresh blood. The whole is well stirred from time to time for 48 hours, and the clear liquor is siphoned off from the precipitate. The precipitate is well washed with water, dried, and reduced to powder, in which state it may be kept for any length of time.

TOUCH PAPER. This paper is prepared by immersing purple or blue paper in a solution of nitrate of potash in spirits of wine or vinegar, and carefully drying it.

When the touch paper is used with small articles, a piece is tied round the orifice with thread, leaving sufficient paper to form a small tube at the end. This tube is filled with gunpowder, and the paper twisted over it, when all is ready for firing.

Touch paper for capping every description of fireworks, such as squibs, crackers, Roman candles, &c., is prepared in the following manner:——Dissolve 2 oz. of the best saltpetre in 1 quart of warm water, and take care that the water is very clean.

After the mixture has stood for half an hour, pour off 1-1/2 pint into a white basin, then cut your sheets of dark blue double-crown paper in half. The weight of the paper should be 12 or 14 lbs. per ream.

Place the paper on a slab sufficiently large to give you room to use a small piece of sponge, with which you use the liquor to wet your paper. Cover each half sheet with the liquor as quickly as possible, on one side only, and immediately this is done place it on a line, the wet side on outwards, and when nearly dry, if you have a great number of sheets, place them together as evenly as possible under a press for one hour, then lay them out to dry, after which they will be quite smooth and ready for use.

In pasting this paper on the work, take care that the paste does not touch that part which is to burn. To use this paper correctly, cut it in strips sufficiently long to go twice round the mouth of the case, or even more if requisite. When you paste on the strips, leave a little above the mouth of the case not pasted; in small cases a little meal powder is put into the mouth, and then the paper is twisted to a point. In larger cases damp priming is used, and when dry, the capping process is proceeded with.

CRACKERS. The following mixtures are used for ordinary crackers:——

Meal powder parts 5 15 6 8 16
Fine charcoal ” 1 4 —— 2 17
Coarse charcoal ” —— —— 6 —— ——
Sulphur ” —— —— 2 —— 1
Saltpetre ” —— —— 16 1 7

Composition for crackers with Chinese fire——

Meal powder parts 9 6 16
Saltpetre ” 6 8 ——
Sulphur ” 1 2 3
Charcoal ” 1-1/2 1-1/2 2
Fine iron ” 5 —— 7
Sand ” —— 5 ——

Composition for crackers with brilliant fire——

Meal powder parts 8 8 36 18 32
Sulphur ” 1 1-1/2 1 1 3
Iron filings ” 2 2-1/2 —— —— ——
Litharge ” —— —— —— 2 ——
Steel filings ” —— —— 8 3 12

The paper generally used for cartridge is that known as ‘elephant’ or cartridge, the latter being the more frequently employed.

Cartridge paper is employed in the preparation of crackers, which vary from 12 to 15 inches, and 3-1/2 inches diameter. One edge of the paper is folded down about 3/4-inch in breadth, then the double edge is turned down about 1/4-inch, and the single edge is bent back over the double fold so as to form a channel 1/4-inch wide. This is filled with meal powder, which is then to be covered by the folds on each side, when the whole is to be pressed very smooth and close, by passing it over the edge of a flat ruler. The part containing the powder is to be gradually folded into the remainder of the paper, each fold being carefully pressed down. The cracker is then doubled backwards and forwards into as many folds of about 2-1/4 inches as the paper will allow.

The whole is pressed together by means of a wooden vice, a piece of twine is passed twice round the middle across the folds, and the joinings are secured by causing the twine to take a turn round the middle at every turn. One of the ends of the folds may be doubled short under, which will produce an extra report, but the other must project a little beyond the rest, for the priming and capping with the touch paper. When these crackers are fired they give a report at every turn of the paper.

The crackers may also be made of two single cards, rolled over each other and covered with paper coated with paste. The crackers are partially filled with the composition by means of a tin funnel. Ordinary powder is then introduced, and the remaining space is filled with a little sawdust.

REVOLVING CRACKERS. These crackers are charged at each end with clay to a depth of two lines, and filled with a composition without gunpowder. The clay prevents the fire streaming out at the ends, and it escapes through two holes placed opposite each other. The two holes are united at the same time by connecting them by means of a quick-match, and a rotatory motion is thus communicated to the cylinder.

ENGLISH PIN WHEELS. Pin, or Catherine wheels are of very simple construction. A long wire about 3/16th of an inch in diameter is the former; on this wire are formed the pipes, which being filled with composition, are afterwards wound round a small circle of wood so as to form a helix or spiral line. The cases are generally made of double-crown paper (yellow wove), and cut into strips to give the greatest length, and of width sufficient to roll about four times round the wire, and pasted at the edge so as to bite firmly at the end of the last turn. When a number of pipes are made and perfectly dry, they are filled with composition. These cases are not driven for filling, but are filled by means of a tin funnel with a tube 3/4 of an inch long, made to pass easily into the mouth of the case, which is gradually filled by lifting a wire up and down in this tube, the diameter of the charging wire being half that of the tube. The dry composition being placed in the funnel, the moment an action of the wire takes place the composition begins to fall into the case, which the charging wire compresses by continuous motion until you have filled the pipe to within 3/4 of an inch of the top. The pipe is then removed, and the mouth neatly twisted, which will be the point for lighting.

When a number of pipes are ready, place them on a damp floor, or in any damp situation, until they become very pliant, but by no means wet; then commence winding them round a circle of wood whose substance must be equal to the thickness of the diameter of the pipe; and when wound, secure the end with sealing-wax, to prevent its springing open; after winding the required quantity let them dry. Now cut some strips of crimson or purple paper 3/16th of an inch wide, and in length twice the diameter of the wheel; then paste all over thoroughly. Take a strip and paste it across the wheel diametrically, rub it down, then turn the wheel over, and place the ends down to correspond with the opposite side; when dry, the wheel will be ready for firing.

They may be fired on a large pin or held in the hand, but it is preferable to drive the pin into the end of a stick, which will prevent any accident, should a section of the wheel burst.

SQUIBS. These are either filled with grained powder, or with a mixture consisting of:——Gunpowder, 8 parts; charcoal, 1 part; sulphur, 1 part. The cases, which are about 6 inches long, are made by rolling strips of stout cartridge paper three times round a roller, and pasting the last fold. They are then firmly tied down near the bottom, and the end is either dipped into hot pitch or covered with sealing-wax. The cases are filled by putting a thimble full of the powder in, and ramming it tightly down with a roller, this operation being continued until the case is filled. It is then capped with touch paper.

SERPENTS (MARROON SQUIBS). A suitable case being ready, it is filled two thirds up with a powder consisting of:——Saltpetre, 16 parts; sulphur, 8 parts; fine gunpowder, 4 parts; antimony, 1 part. This, after being rammed down into the case tolerably tightly, the remainder of the space is filled with grained or corned powder.

SPARKS. These fireworks differs from stars in size, being very small and made without cases. The English method of preparing them is as follows:——A mixture of

Fine gunpowder 1 part
Powdered saltpetre 3 parts
Powdered camphor 4 ”

is placed in a mortar, and some weak gum-water in which a little gum tragacanth has been dissolved, is poured over it, and the whole worked up into a thin paste. Some lint, prepared by boiling it in vinegar or saltpetre, and afterwards dried and unravelled, is placed in the composition so as to absorb the whole. This is then poured into balls about the size of a pea, dried and sprinkled with fine gunpowder.

In Germany the following compositions are used:

---------------+——+——+——+——+——+——+——+——+——+——+——+——+——+——+
| 1| 2| 3| 4| 5| 6| 7| 8| 9|10|11|12|13|14|
+——+——+——+——+——+——+——+——+——+——+——+——+——+——+
Chlorate of | | | | | | | | | | | | | | |
potash parts |24|40|12|20|——|——|——|40|21|21|14|20|96|40|
Chlorate of | | | | | | | | | | | | | | |
potash and | | | | | | | | | | | | | | |
copper ” |——|——|——|——|——|——|——|——|23|23|——|——|——|——|
Chlorate of | | | | | | | | | | | | | | |
baryta ” |——|——|——|——|18|——|——|——|——|——|——|——|——|——|
Nitrate of | | | | | | | | | | | | | | |
potash ” |——|——|——|——|——|12|26|——|——|——|——|——|——|——|
Nitrate of | | | | | | | | | | | | | | |
lead ” |24|——|——|——|——|——|——|——|——|——|——|——|——|——|
Nitrate of | | | | | | | | | | | | | | |
baryta ” |——|——|——|40|——|——|——|——|——|——|——|——|——|——|
Calomel ” |——|——|——|13| 7|——|——|28|12|12| 4| 8|18|——|
Sulphide of | | | | | | | | | | | | | | |
copper ” |——|——|——|——|——|——|——|28|——|12|6 | 4|——|——|
Sulphate of | | | | | | | | | | | | | | |
strontia ” |——|——|——|——|——|——|——|——|——|——|——|20|72|37|
Oxalate of | | | | | | | | | | | | | | |
soda ” |——|16|10|——|——|——|——|——|——|——|——|——|——|——|
Chalk ” |——|——|——|——|——|——|——|——|——|——| 5|——|——|——|
Powdered | | | | | | | | | | | | | | |
zinc ” |——|——|——|——|——|14|28|——|——|——|——|——|——|——|
Powdered | | | | | | | | | | | | | | |
charcoal ” |——|——|——|——|——| 5|11|——|——|——|——|——|——|——|
Sulphur ” |12|——| 1|13|——|——|——|——|——|——| 6| 3|——|——|
Gum lac ” |1 | 8|——| 1| 3|——|——|——|——|——|——| 2|18| 8|
Soap ” |——| 3| 1|——|——|——|——| 3| 3| 3|——|——|——|——|
Starch ” |——|——|——|——|——|——|——|10|——|——|——|——|——|——|
Sugar ” |——|——|——|——|——|——|——|——| 4| 4|——|——|——|——|
Pine soot ” |——|——|——|——|——|——|——|——|——|——|——|——| 1|——|
---------------+——+——+——+——+——+——+——+——+——+——+——+——+——+——+

The above mixtures are intended to give coloured sparks, according to the numbers.

No. 1 gives a bluish-white colour.
” 2 and 3 give yellow.
” 4 gives green.
” 5 gives green.
” 6, 7, 8, 9 and 10 give blue.
” 11 and 12 give violet.
” 13 gives red.
” 14 gives purple.

The materials are mixed with a small quantity of a solution of starch, so as to form a thick paste, which is forced through a perforated plate, the holes in which are twice as large as it is intended the sparks should be on drying. The small pieces fall on a pasteboard, to which the workman gives a rapid horizontal motion to round the grains. They are then dried, and those which are perfectly round are selected and separated by sieves of different meshes to collect those of the same size together.

CHINESE FIRE.

_Red Chinese or Gerbe Fire._

Calibre of the case. Saltpetre. Sulphur. Charcoal. Iron Sand.
1st order.

12 to 16 lbs. 1 lb. 3 oz. 4 oz. 7 oz.
16 to 22 ” 1 ” 3 ” 5 ” 7 ” 8 drms.
22 to 36 ” 1 ” 4 ” 6 ” 8 ”

_White Chinese Fire._

Calibre. Saltpetre. Bruised Powder. Charcoal. Iron Sand.
3rd order.

12 to 16 lbs. 1 lb. 12 oz. 7 oz. 8 drms. 11 oz.
16 to 22 ” 1 ” 11 ” 8 ” 11 ” 8 drms.
22 to 36 ” 1 ” 11 ” 8 ” 8 ” 12 ”

The iron sand is moistened with a little spirits of wine, and then mixed with the charcoal and saltpetre, which have been previously incorporated in another mortar.

SIMPLE STARS OR FIREBALLS. These are generally used in combination with other arrangements, &c., and the composition of which they are made, consists of——saltpetre, 16 parts; sulphur, 8 parts; fine gunpowder, 3 parts.

These materials are mixed with gum and as little spirits of wine as will suffice to make a very stiff paste. This paste is cut up into small squares, which are rolled up into balls on a board covered with gunpowder.

The gunpowder, which adheres, serves for the purpose of firing them. When perfectly dry, they are ready for use.

GERBES. These fireworks display themselves as luminous jets of fire somewhat resembling a water spout. Previously to putting in the brilliant composition, put two scoops of first firing or preparatory fire, for which the following will suit, in cases not larger than 1/4 lb. size:——16 oz. meal powder, 6 oz. saltpetre, 3 oz. sulphur, 3 oz. fine coal. It is important to see that the interior of the cases are quite smooth and free from wrinkles.

GOLD RAIN. The larger rockets are filled with this material, which consists of small squares made in the same way as the simple stars. It is composed as follows:——

Ordinary. Chinese. Composition for
immediate use.

Saltpetre parts 16 4 Saltpetre parts 4
Sulphur ” 8 2 Sulphur ” 2
Fine charcoal ” 2 4 Fine small coals ” 1
Pine soot ” 2 —— Fine gunpowder ” 8
Meal powder ” 4 16 Coarse cast iron ” 4

A portion of the cotton is softened in linseed oil and the materials prepared in a mortar with water.

ROMAN CANDLES. These are made somewhat like gerbes and filled with the same materials, the only difference being that _stars_ are placed between the different layers of substances. The materials must not be too tightly rammed down or the stars will be destroyed.

SIMPLE STARS OR FIREBALLS. Take of saltpetre 16 parts, sulphur 8 parts, fine gunpowder 3 parts; mix them with gum and only just enough spirits of wine to make a very stiff paste. Cut this up into small squares, and roll into balls covered with gunpowder. When properly dry they are ready for use.

MARROONS. These are small cubical boxes filled with an explosive composition which explodes suddenly, making a loud report. They are generally used in combination with other fireworks. The boxes are made of pasteboard, the corners being made tight by pasting paper over them, but leaving the top open until they are filled. They are filled with coarse gunpowder, when the top is closed with strong paper well cemented, and the whole box is wrapped round two or three times with lind cord dipped in strong glue. A hole is made in one of the corners, into which a quick-match is introduced, and the marroon is ready for action.

The reader who may be desirous of further information on the subject of Pyrotechny, cannot do better than consult the article on the subject in ‘Knapp’s Chemical Technology,’ edited by Messrs. Richardson and Watts.[124]

[Footnote 124: Vol. 1, part 4, No. 1. Ballière & Co.]

To this work we are indebted for much of the material contained in the present papers. See COLOURED FIRES.

=PYROXYL′IC SPIRIT.= See SPIRIT (Pyroxylic).

=PYROX′YLIN.= _Syn._ FULMINATING COTTON, GUN-COTTON. A highly inflammable and explosive compound, discovered by Schönbein. It is obtained by the action of nitric acid on cotton (cellulin, C_{6}H_{10}O_{5}), in the presence of sulphuric acid.

By varying the strength of the nitric acid three kinds of gun-cotton may be obtained, called respectively mononitro-cellulin [C_{6}H_{9}(NO_{2})O_{5}], dinitro-cellulin [C_{6}H_{8}(NO_{2})_{2}O_{5}], and trinitro-cellulin [C_{6}H_{7}(NO_{2})_{3}O_{5}]. The first is but slightly explosive; the second is not sufficiently explosive to be used as a substitute for gunpowder, but is best adapted for the preparation of collodion; the third is highly explosive, and is the variety employed in mining and military operations, &c.

_Prep._ 1. (B. P., DINITRO-CELLULIN.) Cotton-wool, 1; sulphuric acid, 5; nitric acid, 5; mix the acids, immerse the cotton, and stir with a glass rod for three minutes, or until it is thoroughly wetted, then remove it, and thoroughly wash out the acid, so that the washings cease to produce a precipitate with chloride of barium. Drain on filtering paper, and dry in a water bath. Used in the preparation of COLLODION.

2. Concentrated nitric acid (sp. gr. 1·500) and concentrated sulphuric acid (sp. gr. 1·845) are mixed together in about equal measures; when the mixture has become cold it is poured into a glass or wedgwood-ware mortar or basin, and clean, dry carded cotton, in as loose a state as practicable, is immersed in it for 4 or 5 minutes, the action of the liquid being promoted by incessant stirring with a glass rod; the acid is next poured off, and the cotton, after being squeezed as dry as possible, by means of the glass stirrer, or between two plates of glass, is thrown into a large quantity of clean soft water, and again squeezed to free it from superfluous moisture; it is then washed in a stream of pure water until it becomes perfectly free from acid, and is, lastly, carefully dried by the heat of hot water or steam, at a temperature not higher than about 180° Fahr. 3. (Schönbein.) Nitric acid (1·45 to 1·50), 1 part; sulphuric acid (1·85), 3 parts (both by volume); proceed as above, but, after the cotton has been squeezed from the acid, allow it to remain in a covered vessel for an hour before washing it, and after washing it, dip it into a solution of carbonate of potassa, 1 oz., in pure water, 1 gall., then squeeze, and partially dry it; next dip it into a weak solution of nitre, and dry it in a room heated by hot air or steam to about 150° Fahr. (See Patent Specif.)

4. (Von Lenk.) The cotton, having been thoroughly cleansed and dried, is steeped, as above, in a mixture of nitric and sulphuric acids (the strongest obtainable in commerce), squeezed as dry as possible, and immersed in a fresh mixture of strong acids, being allowed to remain in this second mixture 48 hours. It is then washed in a stream of water for several weeks, and finally treated with a solution of silicate of potassa (soluble glass). This is the celebrated Austrian gun-cotton which was reported on so favorably by a committee of the British Association in 1863. The treatment with silicate of potassa is adopted merely for the purpose of retarding the combustion.

5. (‘Bulletin de St Pétersbourg,’)——_a._ Take of powdered nitre, 20 parts; sulphuric acid (1·830 to 1·835), 31 parts; dissolve in a glass vessel, and, whilst the solution is still warm (122° Fahr.), add of dry carded cotton 1 part, and employ agitation until this last is well saturated; then cover over the vessel with a plate of glass, and let it stand, for 24 hours, at a temperature of about 86° Fahr.; next well wash the cotton, as above, first with cold and afterwards with boiling water, and dry it carefully at a very low temperature.

_b._ From sulphuric acid (containing 3 equiv. of water), 13 parts; nitric acid (monohydrated), 12 parts; carded cotton, 1 part; the immersion being limited to one hour at a temperature of from 104° to 122° Fahr. (See ‘Pharm. Journ.,’ vol. xiii, No. 2.)

_Prop., &c._ Pyroxylin explodes, with a very sudden flash, and the development of very little heat, without either smoke or residue, at a temperature of about 300° Fahr. (No. 3 at 277° Fahr.). Several modifications of pyroxylin are known, varying considerably in composition, though they all contain the elements of hyponitric acid, and are all explosive. Some are insoluble in a mixture of ether and alcohol, whilst others are readily dissolved, forming the glutinous solution which is used in surgery under the name of ‘collodion,’ and which is also extensively used in photography. The best gun-cotton (Von Lenk’s) is of no use whatever for making collodion. The pyroxylin prepared by the formula 5, _a_ (_above_), is soluble in a mixture of 7 parts of ether and 1 part of alcohol; whilst the product of 5, _b_, if prepared by 2 hours’ digestion instead of 1, is said to be even soluble in absolute alcohol.

_Obs._ General von Lenk has overcome all the difficulties which have hitherto prevented gun-cotton being used in place of gunpowder. By spinning the gun-cotton into thread or yarn, and weaving this into webs, he has succeeded in making cartridges which will produce the exact amount of force required. The time needed for the complete ignition of the cartridge can be diminished or increased at pleasure by varying the mechanical arrangement of the spun threads. Each gun and each kind of projectile requires a certain density of cartridge. In general, it is found that the proportion of 11 lbs. of gun-cotton occupying 1 cubic foot of space produces a greater force than gunpowder of which from 50 to 60 lbs. occupies the same space, and a force of the nature required for ordinary artillery. See COLLODION and XYLOIDIN; consult also Abel’s researches in the ‘Transactions of the Royal Society.’

=QUACK MED′ICINES.= See PATENT MEDICINES, OINTMENT, PILLS, &c.

=QUAIL.= The _Coturnix vulgaris_, a gallinaceous bird, allied to the partridge, but of smaller size. Its flesh is highly esteemed by epicures. It is imported from Turkey, preserved in oil; and from Italy, potted with clarified butter.

=QUARANTINE.= The old laws of Quarantine, as the French derivation of the word indicates, compelled a vessel coming from the shores of a country liable to, or ravaged by, an infectious disease, such as plague, to those of a region free from contagion, to undergo forty days’ isolation before it was unladen, or its passengers were allowed to land at the healthy port.

In Europe these ancient enactments against the importation of infection are still more or less vexatiously enforced in Spain, Portugal, Greece and Turkey; and in a modified form at Malta and some of the French and Italian ports. In the Mediterranean ports, ships coming from countries which lie in the southern or eastern shores of that sea are usually subjected to a quarantine of from six to fifteen days, during which period the passengers are confined in a sort of barrack called a ‘lazaretto,’ the merchandise, letters, &c., of the vessel being in the meantime frequently fumigated, or otherwise disinfected.

The inconveniences to commerce and the necessary intercourse between nations attending the too rigorous carrying out of quarantine have, within the last twelve years, led to a series of sanitary international conferences between the European Governments, with the object of divising some methods which, without weakening the safeguards to the public health, should as much as possible reduce the inconveniences attending the enforcement of quarantine to a minimum. At the last of these conferences, which was held at Vienna in 1873, the members were almost unanimous in advising the abolition of quarantine on European rivers.

Until within the last twenty years the old quarantine laws were pretty strictly enforced in this country. Since this time, however, they have been considerably relaxed, or, we should rather say, superseded by the following ordinances, which, upon the authority of an order in council of July 31st, 1871, can be enforced in the case of suspected vessels.

This ordinance declares that it is lawful for a sanitary authority, having reason to believe that any ship arriving in its district comes from a place infected with cholera, to visit and examine the ship before it enters the port.

Art. 3 provides that the master of a cholera-infected ship, or one that has even been exposed to the infection of cholera, is to moor, anchor, or place her in such a position as from time to time the sanitary authority shall direct.

Art. 4 provides that no person shall land from any such ship until after the examination.

Art. 5 provides for the proper examination of all persons on board by a legally-qualified practitioner, and permits those not suffering from cholera to land immediately.

Another order in council, dated August 3rd, 1874, empowers any custom-house officer, or other person having authority from the Commissioners or Board of Customs, at any time before the Nuisance Authority shall visit and examine the ship, to detain the ship.

“No person shall, after such detention, land from the ship, and the officer shall forthwith give notice of the detention, and of the cause thereof, to the proper nuisance (local) authority; and the detention shall cease as soon as the nuisance authority shall visit and examine the ship, or at the expiration of twelve hours after notice shall have been given to such nuisance authority.”

Another order in council, dated August 5th, 1871, directs that the master of a vessel, in which cholera has existed, shall not be allowed to bring his vessel into port until he has destroyed the infected clothes and bedding.

Local Government Boards are also invested with considerable executive powers, by which they are enabled to enforce quarantine during the prevalence of any contagious disease in other countries. The main Act, however, relating to quarantine, is the 6th of Geo. IV., c. 78; and all vessels having on board any person or persons affected with a dangerous or infections disorder, are to be deemed as coming within its provisions (see ‘Public Health Act,’ Schedule v., part 3). There is a land, as well as a sea quarantine. Thus, for instance, in some countries, more particularly those of Eastern Europe, the former is still in force on the frontiers of contiguous States, to the great impediment of commerce and inconvenience of travellers.

The late outbreak of plague in Astrakan has led to its being established and very strictly carried out on the borders of Russia, Austria, Hungary, and Germany.

Hecker, writing on the probable origin of quarantine, remarks:——“The fortieth day, according to the most ancient notions, has always been regarded as the last of ardent diseases, and the limit of separation between these and those which are chronic. It was the custom to subject lying-in women for forty days to a more exact superintendence.

There was a good deal also said in medical works of forty days’ epochs in the formation of the fœtus, not to mention that the alchemists always expected more durable revolutions in forty days, which period they called the philosophical month. This period being generally held to prevail in natural processes, it appeared reasonable to assume and reasonably to establish it; as that required for the development of latent principles of contagion, since public regulations cannot dispense with decisions of this kind, even though they should not be wholly justified by the nature of the case. Great stress has also been laid on theological and legal grounds, which were certainly of greater weight in the fifteenth century than in modern times; such as the forty days’ duration of the flood; the forty days’ sojourn of Moses on Mount Sinai; our Saviour’s fast for the same length of time in the wilderness; lastly, what is called the Saxon term, which lasts for forty days.

=QUAR′TAN.= Occurring every fourth day.

=QUARTA′TION.= The practice, among assayers, of alloying 1 part of gold with 3 parts of silver, before submitting it to the operation of ‘parting,’ in order that its particles may be too far separated to protect the copper, lead, palladium, silver, or other metals, with which it is contaminated, from the solvent action of the nitric or sulphuric acid, as the case may be. See ASSAYING.

=QUARTZ.= Pure native silica. It is an essential constituent of granite and many other rocks. Its crystalline, transparent varieties, are known as rock crystal. See GLASS, POWDER, &c.

=QUASS.= _Syn._ POSCA VENALIS, L. _Prep._ Mix rye-flour and warm water together, and keep the mixture by the fireside until it has turned sour. Used as vinegar in Russia.

=QUAS′SIA.= _Syn._ QUASSIA (Ph. L., E., & D.; QUASSIA LIGNUM, QUASSIA WOOD, B. P.). The “wood of _Picræna_ (_Picrasma_) _excelsa_, Lindl.” (B. P., Ph. L.), or _Jamaica quassia_; and also of the “_Quassia amara_, Linn.” (Ph. E.), or _Surinam quassia_. The latter is the original quassia, but it is no longer imported. Quassia is characterised by its intense bitterness. It is reputed tonic and stomachic, assisting digestion, and giving tone and vigour to the system. Its name was given to it by Linnæus, in honour of a negro slave who had long employed it as a remedy for the malignant endemic fevers of Surinam. When sliced, it forms the ‘quassia chips’ of the shops. It is generally taken in the form of infusion. This last, sweetened with sugar, forms a safe and effective poison for flies.——_Dose_ (in powder), 10 to 20 gr.

ROASTED QUASSIA, reduced to powder, is largely employed, instead of hops, to embitter porter; and the unroasted powder is used for the same purpose in the adulteration of the bitter varieties of ale.

=QUAS′SIN.= _Syn._ QUASSITE, QUASSINA. A peculiar bitter principle, obtained by precipitating decoction of quassia with milk of lime, evaporating the filtrate, dissolving the residue in alcohol, treating with animal charcoal, again evaporating, dissolving in water, and crystallising. 8 lbs. of quassia chips yield 1 drachm.

=QUEEN’S BLUE.= Thumb blue. See BLUE.

=QUEEN’S MET′AL.= A species of pewter used for teapots, &c., made by fusing under charcoal a mixture of tin, 9 parts, and antimony, bismuth, and lead, of each 1 part; or, tin, 100 parts; antimony, 8 parts; copper, 4 parts; bismuth, 1 part. See BRITANNIA METAL and PEWTER.

=QUEEN’S YEL′LOW.= Subsulphate of mercury.

=QUERCITRIN.= The bark of the _Quercus tinctoria_ yields a neutral substance, to which the above name has been given. Quercitrin may be prepared as follows by the process of Rochleder:——The bark is boiled with water, the decoction is left to cool, and the impure quercitrin which separates is collected, then rubbed to a pulp with alcohol of 35° B., heated over the water bath, collected on linen, and pressed, whereby the principal impurities are removed. The residue is dissolved in a larger quantity of boiling alcohol, the solution is filtered hot, and water is added to it until it becomes turbid, so that the greater part of the quercitrin separates before the liquid is cold. It is then collected, pressed, and purified by a repetition of the same treatment.

Another process, by Zwenger and Dronke, is this:——The bark, in small pieces, is exhausted with boiling alcohol, the alcohol is distilled off, and the residue, while still warm, is mixed with a little acetic acid, and then with neutral acetate of lead; the filtrate, freed from lead by sulphuric acid, is evaporated, and the quercitrin which crystallises is purified by repeated crystallisation from alcohol.