Part 4
_Fish poisoning._ It is a not unfrequent occurrence to find fish when eaten giving rise to a species of poisoning of a more or less violent form, such as a sense of weight at the stomach, accompanied with nausea, vertigo, headache, heat about the head and eyes, pains in the stomach, thirst, and often an eruption of the skin resembling nettle-rash. These symptoms may be sometimes due to the nature of the fish itself; sometimes to its being in a state unfit to be taken as food, as, for instance, when it is in a stale or decomposing condition; and occasionally to the peculiarity of constitution of those who partake of it, even if in a perfectly fresh condition. Whenever any of the symptoms above described follow from eating fish, an emetic of mustard and water (a teaspoonful of mustard in half a pint of water) should be administered. If subsequently a rash should appear, it would be well to take a dose of brisk purgative medicine, and, if necessary, a few doses of carbonate of soda 3 or 4 times during the day.
_Poisonous Mushrooms._ The same treatment should be followed as for fish. With some people the edible mushroom acts as a poison.
_Sinks._ See that these be securely trapped, and in the event of any unpleasant smell from them, pour down some disinfectant, such as chloride of lime, carbolic acid, or Condy's fluid. The foul emanations from a sink ought to be regarded as of a most dangerous and pestilential nature.
=Accidents to Children.= Many, if not most, of the casualties to which children are exposed are given above, together with the best course to be pursued in the event of their being overtaken by any of them. There are, however, a few forms of disaster which seem more especially peculiar to children. Of these we may select--
_Swallowing a piece of broken glass._ In this case avoid giving purgatives, but give solid farinaceous food, so as to envelope the glass and enable it to pass through the bowels without causing injury by coming in contact with them.
_Swallowing a coin._ Give a dose or two of castor oil, and examine the stools until the coin is perceived.
_A small coin sticking in the windpipe._ Seize the child by the legs, letting his head hang downwards, then administer several brisk blows on the back with the palm of the hand, when very frequently the coin will be coughed out of the mouth and on to the floor. If this plan do not succeed, send immediately for medical aid.
=ACCLI'MATE=, or =ACCLI'MATISE=. In _botany_ and _zoology_, to inure a plant or animal to a climate to which it is not indigenous. When so inured it is said to be ACCLIMATED. In _medicine_, to habituate the body to a foreign climate, so that it may not be peculiarly liable to its endemic diseases; or to become so habituated. Thus, a person who has resided several years at New Orleans without an attack of yellow fever, or having had an attack has satisfactorily recovered, is said to be ACCLI'MATISED.
=ACCOM'PANIMENTS.= In _cookery_ and _housekeeping_, see TRIMMINGS.
=ACCUMULA'TION.= [Eng., Fr.] _Syn._ ACCUMULA'TIO, L. In _medicine_, a term applied when the effects of the first dose of any substance still continue when the second is administered (accumulation of action); or when several doses of insoluble substances remain inactive in the system until their energy is developed by chemical influence (accumulation of doses). See MEDICINES, POISONS, &c.
=ACEPH'ALANS.= _Syn._ ACEPH'ALA, CUV. In _malacology_, a class of aquatic mollusca, having no apparent head, but a mouth between the folds of their mantle. Several of them, as the oyster, cockle, mussel, scallop, &c., are consumed for food.
=ACERB'ITY.= _Syn._ ACERB'ITAS, L.; ACERBITÉ, Fr.; HERBIGKEIT, Ger. In _chemistry_, &c., sourness, with bitterness and astringency, or harshness. See CIDER, FRUIT, WINE, &c.
=ACERBO'S ANTI-RHEUMATIC AND ANTI-CATARRH OIL.= For various horse diseases. Gum euphorbium, 10 parts; absolute alcohol, 10 parts; olive oil, 80 parts. Digest in a warm-water bath for 24 hours, then boil until all the spirit has evaporated, and, when cold, strain through cotton. (Hager.)
=ACER'IDES.= Plasters that do not contain wax.
=ACES'CENT.= _Syns._ ACES'CENS, L.; ACESCENT, AIGRELET, Fr.; SÄURLICH, Ger. In _chemistry_, &c., growing sour; slightly tart or acid; having a tendency to sourness, or to run into the acetic fermentation, as _wine_, _beer_, _malt-wort_, &c. Hence, ACES'CENCE or ACES'CENCY (_acescen'tia_, L.; _acescense_, _aigreur_, Fr.; _säurlichkeit_, Ger.), the tendency to become slightly acid, or the quality of being so. See ACETIFICATION, MALT-LIQUORS, WINE, WORT, &c.
=ACETA''RIOUS= (-t[=a]re'-e-[)u]s). Used for salads (as plants); relating to salads (which see).
=AC'ETATE= ([)a]s'-). _Syn._ ACE'TAS, L.; ACETATE, Fr.; ESSIGSÄURE SALZE, Ger. In _chemistry_, a salt consisting of C_{2}H_{3}O_{2} (sometimes called the acid-radical of the acetates) with hydrogen, a metal, or a compound basic radical; _e.g._,
Hydrogen acetate (acetic acid) HC_{2}H_{3}O_{2} Potassium acetate KC_{2}H_{3}O_{2} Lead (plumbic) acetate Pb(C_{2}H_{3}O_{2})_{2} Ammonium acetate NH_{4}C_{2}H_{3}O_{2} Salts of acetic acid (HC_{2}H_{3}O_{2}) with the alkaloids are likewise termed acetates; _e.g._, Morphia acetate C_{17}H_{19}NO_{3} . C_{2}H_{4}O_{2}
_Prep._ That of the commercial acetates, and of many others, is noticed under the respective metals. In general, they may all be formed by direct solution of the carbonate, hydrate or oxide of the metal whose acetate it is desired to form, in dilute acetic acid; or from a solution of an acetate and of another salt of the metal, by double decomposition. In either case, the resulting solution must be carefully evaporated by a gentle heat, and, where possible, crystallised.
_Prop., &c._ All the neutral acetates, except those of molybdenum and tungsten, are more or less soluble in water, several so much so as to be uncrystallizable; many dissolve in alcohol; they suffer decomposition at a dull red heat, and by distillation, at that temperature, yield acetone and water, or acetone and acetic acid, and leave a carbonaceous residuum; at a full red-heat, those of potassium, sodium, barium, strontium, calcium, and magnesium, are converted into carbonates, whilst the other metallic acetates leave behind the pure metal, or its oxide. The aqueous solutions of the alkaline acetates soon turn mouldy and suffer decomposition. No more of them should, therefore, be dissolved at once than is required for immediate use.
_Char., tests, &c._ The acetates are known--1. By evolving fumes of acetic acid, recognisable by its peculiar and characteristic odour, on the addition of strong sulphuric acid:--2. By evolving the vapour of acetic ether (known by its peculiar and agreeable odour) when heated with a mixture of about equal parts of concentrated sulphuric acid and alcohol.
=AC'ETATED= ([)a]s'-). In _chemistry_ and _pharmacy_, combined or impregnated with acetic acid or vinegar.
=ACE'TIC.= _Syn._ ACE'TICUS, L.; ACÉTIQUE, Fr. Of or relating to vinegar; made with acetic acid, as perfumes, &c. (See _below_.)
=ACETIC ACID.= HC_{2}H_{3}O_{2}. _Syn._ PYROLIG'NEOUS ACID (_pure_); ACID OF VINEGAR; ACIDUM ACE'TICUM, L.; ACIDE ACETIQUE, Fr.; ACIDO ACETICO, It.; ESSIGSÄURE, Ger.; AZYNZUUR, Dut.; EISEL, Sax. When free from water it crystallises on cooling, and is distinguished as--ACETIC HYDRATE, HY'DRATED ACETIC ACID, MONOHY'DRATED A. A., GLA'CIAL A. A., MONOHYDRATED A. A., ACE'TUM GLACIA'LE, ACIDUM ACE'TICUM G., L., &c. the sour principle of vinegar.
_Var._ Commercial acetic acid is found under the form of the pure acid of the chemist and pharmaceutist (glacial and dilute), and of vinegar, of which there are several varieties, which are noticed under their respective heads.
_Sources._ Fermented liquors; the vinegars of commerce; alcoholic liquors; wood, from which it is obtained, as pyroligneous acid, by distillation; the commercial acetates of soda, potassa, lime, lead, copper, &c. The pure acetic acid of the chemist and of commerce is almost wholly obtained from the acetates, either by the action of a strong acid, which seizes on the base, setting the acid free; or, by dry distillation, in which the high degree of heat employed separates the acetic acid from the base in the form of vapour. It is also obtained by the oxidation of alcohol.
_Prep._ The following are the principal processes at present adopted to obtain pure acetic acid:--
1. From the _Acetates_ in the moist way:--
_a._ From ACETATE OF SODA:--
1. Commercial acetate of soda (_i.e._, the 'pure acetate' of the pyroligneous acid works), in crystals, is put into the body of a stout copper still, and a deep cavity being made in the centre of the mass, about 35% of sulphuric acid of a sp. gr. of not less than 1·84 is poured in; the walls of the cavity are then thrown in upon the acid, and the whole briskly agitated, for a very short time, with a large wooden spatula; the head of the still is next luted on, and the distillation conducted at a gentle heat, the receiver being changed as soon as the distillate begins to acquire a slight empyreumatic odour. The product, when the process is well managed, is an almost colourless acid of the sp. gr. of fully 1·05, containing about 40% of glacial acid, or between 34% and 35% of anhydrous acid. Any trace of colour or empyreuma is removed by agitation with some well-washed and recently ignited vegetable charcoal, or with a very small quantity of recently ignited purified animal charcoal, and subsequently passing it through a prepared calico bag-filter; or by allowing it to stand, for about a fortnight, in barrels containing some beech-wood chips; after which it is ready for sale, either as the ordinary acetic acid or pure pyroligneous acid of commerce, or (on dilution, &c.) as vinegar.
2. The acid of sp. gr. 1·05 (obtained as above) is distilled with fused chloride of calcium, the distillate being run into a refrigerator; the crystals that form are drained at a temperature below 40° or 45° Fahr., and after removal to a warmer temperature, where they liquefy, and agitation with a little peroxide of lead, are submitted to a second distillation, as before; and this is repeated until the whole of the acid crystallises at 51° Fahr. The product is the glacial acetic acid of commerce.
_Obs._ The above are the processes usually adopted, on the large scale, in this country.
3. (M. Mollerat's process--without distillation.) Pure commercial acetate of soda, in coarse powder, is placed in a hard glazed stoneware or glass pan or receiver set in a cool situation, and 35% or 36% of concentrated sulphuric acid, of the sp. gr. 1·843, added, in such a manner that the acid may flow under the powder, and little heat be generated by the operation; the whole is then allowed to remain in contact (covered) for some hours, when crystalline grains of sulphate of soda are found covering the bottom and sides of the vessel, and hydrated acetic acid, partly liquid and partly in crystals, the upper portion. The temperature being now slightly raised to a point just sufficient to cause the liquefaction of the crystals of acetic acid (_i.e._, to from 62° to 65° Fahr.), the fluid is poured off, and a very small quantity of pure acetate of lime added to it gradually, until it ceases to yield any trace of free sulphuric acid on evaporation. After sufficient repose it is carefully decanted for use. An excellent commercial strong acetic acid is thus obtained, without distillation, owing to the insolubility of sulphate of soda in acetic acid; and from which glacial acid may be procured by refrigeration. If, however, the process be badly managed, or the proportions of the ingredients be not carefully observed, the product will be contaminated with either a little sulphuric acid or saline matter. It is also important to the success of this process that it be performed in a cool apartment, and in well-cooled vessels. Perfectly pure acetic acid may easily be obtained by rectification from this acid. The above plan of superseding a troublesome distillation is one of the greatest improvements yet introduced into the manufacture of acetic acid.
4. (Liebig's process.) Pure acetate of soda, thoroughly dried and finely powdered, 3 parts, is placed in a capacious retort, and pure concentrated sulphuric acid, 9·7 parts, poured over it through the tubulature. One eighth of the acetic acid passes over by the heat developed by the reaction of the ingredients. The heat of a sand bath is next applied and continued until the contents of the retort become quite liquid. The distillate, carefully rectified, yields two parts of pure acid, containing only 20 per cent. of water. On exposing the latter portion which comes over in a closed vessel to a temperature below 40° Fahr., crystals of hydrated acetic acid are deposited. The weaker, or liquid portion, being poured off, the crystals are again melted and re-crystallised by cooling. The crystals of the last operation, separated from the liquid, and carefully drained in a cool and closed vessel, are perfectly pure hydrated acetic acid.
_Obs._ The above is an excellent process for obtaining a chemically pure acid. The excess of sulphuric acid left from the process may be recovered by distillation; or the whole residuum may be employed in a second distillation with fresh acetate.
Although a retort is recommended by Liebig for the distillation, and is usually adopted, on the small scale, for the purpose, a flask closed by a cork perforated by two tubes, as exhibited by the _engr._, will be found more convenient and safe; as the product is then less likely to be contaminated by the 'spirting' of the ingredients over the brim of the vessel. The heat of a diffused gas-flame may also be often advantageously substituted for a sand bath.
_b._ From ACETATE OF POTASH:--
1. Acetate of potash (fused and powdered) is placed in a still, or other suitable vessel, and 50% of the strongest sulphuric acid ('oil of vitriol' of fully 1·84 sp. gr.) being added, the mixture is distilled to dryness, as before. The product is 50 to 51% of the weight of the acetate employed, with a sp. gr. of about 1·0735 to 1·074, containing about 66% of anhydrous acetic acid, or nearly 80% of ordinary glacial acid. By rectification from a little dried acetate of lead a perfectly pure acid of almost any strength may be obtained. The ingredients are nearly in equiv. proportions.
_c._ From ACETATE OF LEAD:--
1. (Ure.) Take of dried acetate of lead, 4 parts; strongest oil of vitriol, 1 part. Distil slowly to dryness. Nearly equal to the last.
2. (Liebig.) Acetate of lead, 3 parts; sulphuric acid, 8 parts; as before.
3. (Dollfuss' Concentrated Acetic Acid.) Take of dried acetate of lead, 12 oz.; sulphuric acid, 6 oz.; distil 7 ounces.
_d._ From ACETATE OF LIME:--
1. (Christl.) Raw acetate or pyrolignate of lime (prepared by Völckel's process), 100 parts, is mixed with hydrochloric acid (20° Baumé, or sp. gr. 1·1515), 120 parts; and after 12 hours, distilled in a copper vessel, with a gradually applied heat. The product is 100 parts or lbs. of acetic acid of 8° Baumé (sp. gr. 1·0556), containing about 47% of hydrated acid, only slightly coloured and empyreumatic, fit for various manufacturing purposes. The advantage of this process is the low price of hydrochloric acid, and the product not being contaminated with sulphuric or sulphurous acid.
_Obs._ It will be found that pyrolignate of lime generally contains 60% to 70% of neutral acetate; but should it contain either more or less, a proportionate quantity must be employed. When the proper proportions are used the distillate gives only a scarcely perceptible turbid cloud when tested with nitrate of silver. If the hydrochloric acid used has the sp. gr. 1·16, a less quantity being employed, the product will have the sp. gr. of 1·058 to 1·061, and will then contain from 48 to 51% of the monohydrate, or 41 or 42% of anhydrous acetic acid. The resin sometimes found floating on the mixed ingredients should be carefully removed, by skimming, before distillation.
As acid of the above strength is rarely required, and as the distillation is more easily conducted when the ingredients are less concentrated, a little water may be conveniently added either before or towards the end of the distillation. Hence the following proportions have been recommended:--
2. (Völckel.) Acetate of lime (as last), 100 parts; hydrochloric acid (sp. gr. 1·16), 90 to 95 parts; water, 25 parts; mix, and proceed as before. Prod. 96 to 98 parts of an excellent acid, well adapted to trading purposes, having a sp. gr. about 1·050, and containing nearly 40% of hydrated acetic acid. It has been correctly remarked, that the acetic acid produced with hydrochloric acid is always of better quality than that produced with sulphuric acid; being not only less coloured, but also entirely free from sulphurous acid. The distillation uniformly proceeds with ease and regularity, and the whole of the acetic acid passes over between 212° and 248° Fahr.; by which the danger of contamination with other products, resulting from a high degree of heat, is obviated.
3. An Acetic acid sufficiently strong and pure for many ordinary purposes may be obtained without distillation, by pouring strong sulphuric acid, 60 parts, diluted with water, 5 parts, on well-dried acetate of lime, 100 parts; digesting, with occasional agitation in a close vessel, decanting the clear liquid, and straining the remainder.
II. _From_ the _Acetates_ by _dry distillation_ with a _sulphate_:--
_a._ From ACETATE OF LEAD:--
1. Acetate of lead (dried), 5 parts; and sulphate of iron (gently calcined), 2 parts; are separately powdered; and after thorough mixture, carefully distilled, by the heat of a sand bath, into a well-cooled receiver. An economical process for a strong acid, under certain circumstances; but one now seldom adopted.
2. (Bardollier's Strong Acetous acid.) Dried acetate of lead, 10 oz.; calcined green vitriol, 12 oz.; as the last.
_b._ From the ACETATES OF COPPER:--By substituting acetate or diacetate of copper, in equiv. proportions, or better with excess of the sulphate. Seldom used.
_c._ From ACETATE OF POTASH, as the last.
III. From the _Acetates per se_:--
_a._ From ACETATE OF COPPER:--AROMATIC V.[dagger]; SPIRIT OF VERDIGRIS[dagger]; SPIRITUS VEN'ERIS[dagger], L.; ESPRIT DE VENUS, Fr.; ACIDUM ACE'TICUM, (Ph. L. 1787.) _Process._ Carefully dry crystallised verdigris (diacetate of copper) by a very gentle heat, and introduce it into a large stoneware retort (see _engr._), the bottom of which has been previously coated with a mixture of clay and horse-dung, to render it more capable of standing the fire. Next place it in a suitable furnace, and connect it, by an adapter, with 3 or 4 double tubulated globes, the last of which must be furnished with a vertical tubulature, to which a double Welter's safety-tube should be adapted; the other end being immersed in a basin half-filled with distilled vinegar or water, while the funnel portion communicates with the atmosphere. Then place each globe in a basin of water, kept cool by a stream constantly passing through it; and cover the upper portion with cloths kept continually wet with cold water. After 15 or 20 hours, fire may be applied, and must be so regulated that the drops follow each other with considerable rapidity from the end of the adapter, whilst the bubbles of air cause no inconvenience at the other end of the apparatus. If otherwise, the fire must be damped a little. The operation should be continued, and the fire gradually increased, until vapour ceases to come over, known by the globes gradually cooling, notwithstanding the heat of the furnace. The operation being concluded, the whole may be allowed to cool, and the acid collected preparatory to rectification. This may be effected in a similarly arranged apparatus, except that it must be wholly of glass; and the retort should not be much more than half-filled. The operation must now be very carefully conducted, and discontinued before barely the whole of the acid has distilled over; as the last portion is apt to injure the flavour and colour of the rest. The first portions which come over are very weak, and should be kept separate, until the sp. gr. reaches to about 1·372, when the receiver should be changed, and the product collected in separate portions, as noticed below.
_Obs._ Good diacetate of copper yields, by careful management, at a temperature of 400° to 560° Fahr., fully one half its weight of a greenish-coloured acid, of the sp. gr. of about 1·061, containing above 50% of hydrated acetic acid, or 43% of anhydrous acid. 20 lbs. of the ordinary acetate yields 9-3/4 lbs. of this rough acid, leaving a residuum of about 6-1/2 lbs. of metallic copper mixed with a little charcoal, in the retort; the remainder (nearly 2/10ths of the acid in the acetate) being decomposed by the heat, and lost. This 9-3/4 lbs. of crude acid yields by rectification, and dividing the products, 1/2 lb. of acid of the sp. gr. 1·023; 3 lbs. of the sp. gr. 1·042; and 6 lbs. of the sp. gr. 1·065; exclusive of a little acetone which comes over with it. In the first distillation, the strongest acid is found in the third receiver, and the weakest in the first. The acid obtained in this way is always accompanied with a little fragrant pyro-acetic spirit; which renders it preferable for aromatic vinegar and perfumery. It dissolves camphor, resins, and essential oils with facility. This is one of the oldest methods of obtaining glacial acetic acid, and the product is still preferred for some purposes. It is the RADICAL VINEGAR of the alchemists, and it is that which is preferred by the perfumers. Well-dried acetate of lead, or of iron, as well as several other acetates, may be substituted for acetate of copper in the above process; but are less economical and convenient. In all cases, great care must be taken to avoid over-firing, as thereby the quantity obtained is lessened, and the quality injured. The residuum of the distillation is pyrophoric and frequently inflames spontaneously, on exposure to the air. Due caution must be therefore observed regarding it.
IV. _From Wood_, by _dry distillation_. See PYROLIGNEOUS ACID. The preparation of the purified acid, by converting it into an acetate, and subsequent distillation with a strong acid, is noticed _above._