Chapter LXXII: Part 2 (33)

Associated with the pyrites in small quantities are various substances, some of which, becoming volatilised when the ore is burnt, enter the chambers with the mixed gases, and thus find their entrance into the acid, whilst others remain behind in the iron residue of impure ferric oxide, left on the hearth of the furnace after roasting. The former of these foreign bodies, which are found in most commercial acids, are described below under the section “Purification.” Amongst the solid non-volatile matters, the extraction of which from the burnt iron has been found in many works to yield a profit, are zinc, copper, silver and thallium.

At Wolcrum, in Germany, the zinc which exists in the residue in the form of sulphate is extracted by lixiviation, and then treated with common salt, the reaction giving rise to the production of sulphate of soda and chloride of zinc. The soda obtained is sufficient to pay for the working of the operation, whilst a good profit is made by the sale of the large quantities of chloride of zinc which are thus yielded.[213]

[Footnote 213: Ibid.]

The copper, which in some residues is met with to the amount of 4 per cent., also pays for extraction, and is sold to the smelter. It is first converted into chloride, and then precipitated by iron. The silver is recovered by Claudet’s process, which consists in precipitating it from a saline solution in which it is in the state of a soluble chloride, by iodide of potassium.

In the Widnes Copper Works the silver so extracted yields an annual profit of £3000.[214]

[Footnote 214: Ibid.]

Thallium is found in the fine dust caused by the combustion of the pyrites, which dust deposits in the flues between the furnace and the chambers. The metal is extracted from the dust by treating this latter with dilute sulphuric acid. The resulting sulphate is converted into chloride, and again reconverted alternately into sulphate and chloride several times, the sulphate last obtained being reduced by metallic zinc.[215]

[Footnote 215: Ibid.]

Selenium is also a frequent constituent in the flue dust. Some ores, after being subjected to roasting, yield iron capable of being worked. This is more particularly the case with the Spanish and Portuguese pyrites.

The following is an outline of the process by which sulphuric acid is obtained, and of the chemical changes which occur during its manufacture:

The sulphur or sulphide being placed on the hearth of the furnace, shown at A in the accompanying cut, when heated from below, soon takes fire, and combining with the oxygen of the atmospheric air, the admission of which into the furnace is regulated by an experienced workman, by the door shown in the plate, forms sulphurous anhydride. An iron pot, standing on the hearth of the furnace, contains a mixture of nitrate of soda and oil of vitriol, and this becoming heated by the burning sulphur, decomposition of the salt ensues, and fumes of nitric acid are given off. The sulphurous anhydride and nitric acid gases thus formed together with air are carried into large leaden chambers, standing on, and supported by, massive frameworks of stout timber. Steam is admitted continuously by several jets (see plate) into these chambers, which are covered at the bottom with water to a depth of about three inches.

As soon as the mixed gases enter the chamber and come into contact with the steam, the sulphurous anhydride acts on the nitric acid, forming sulphuric acid, which falls into and is absorbed by the water on the floor of the chamber, and nitric oxide, which is liberated in the chamber.

The following equation will illustrate the reaction:

2HNO_{3} + 3SO_{2} + 2H_{2}O = 3H_{2}SO_{4} + 2NO.

170 parts by weight of nitrate of soda are required to oxidise to sulphuric acid 96 parts of sulphur, whereas rarely more, and frequently less, than 5 parts of soda are required by the vitriol maker. This saving of material is effected by the function performed in the chamber by the nitric oxide resulting from the decomposition of the nitric acid.

The nitric oxide reacting upon the air in the chamber abstracts oxygen from it and becomes converted into nitric peroxide, thus:

2NO + O_{2} = 2NO_{2}.

Nitric peroxide is a very unstable compound, and directly it comes into contact with the fresh sulphurous anhydride entering the chamber, it oxidises it in the presence of water to sulphuric acid, thus:

2NO_{2} + 2SO_{2} + 2H_{2}O = 2H_{2}SO_{4} + 2NO.

This deportment of the nitric oxide being continuous, it will be seen it acts the part of a carrier of oxygen from the atmospheric air contained in the chamber to the sulphurous acid, and by so doing (theoretically) renders any further supply of nitrate of soda than that required to start the process unnecessary.

As soon as the water, or rather liquid acid on the floor of the leaden chambers, has acquired the sp. gr. of 1·35 to 1·50, it is drawn off, and concentrated by boiling in shallow leaden pans to the density of about 1·72, after which it is further concentrated in green-glass or platinum retorts, until the sp. gr. reaches 1·842 to 1·846. When of sp. gr. from 1·35 to 1·50 it is called chamber acid, and when of the last strength, is used in the manufacture of salt-cake, sulphate of ammonia, some kinds of manure, and nitric acid. Sulphuric acid of sp. gr. 1·720 is mostly employed in the preparation of superphosphate of lime. After concentration to 1·842 or 1·846, the clear acid is put into large globular bottles of green glass (carboys), surrounded with straw and basket-work, and is sent into the market under the name of ‘oil of vitriol.’

The leaden chambers in which the chemical changes take place, that result in the formation of the acid, vary greatly in dimensions in different works, being sometimes as much as 12 or 15 feet high, 15 or 20 wide, and from 150 to 300 feet long. They are mostly partially divided by incomplete leaden partitions, known as curtains, so arranged on the roof and the floor as to cause the currents of mixed gases to come into collision, and thus cause their admixture. Where there are a number of small separate chambers they are connected by means of leaden tubes. A chamber having a capacity of 25,000 cubic feet will yield 10 tons of acid weekly.

The sheets of lead used in the construction of the chambers are united by fusion, or melting together of their edges. If cement were used it would be speedily attacked and destroyed by the acid and gaseous products.

The process for the manufacture of sulphuric acid above described, was devised in 1774 by a calico printer of Rouen, and improved by Chaptal.

In 1776 the first vitriol factory was set up at Prestonpans, by Dr Roebuck, of Birmingham, with whom originated the idea of the leaden chambers.

Various attempts have been at different times unsuccessfully made to supersede the old process. Of these we may mention:

1. The proposal to oxidise sulphurous acid by means of chlorine in the presence of steam.

2. Persoz’s method to oxidise sulphurous acid by means of nitric acid, and to regenerate the nitric oxide resulting from the reduction of the acid by the oxygen of the air in the presence of steam.

3. _a_, by the decomposition of gypsum by superheated steam at a red heat; or _b_, by decomposing the gypsum by chloride of lead.

The failure of the above and other efforts has led to the chemist turning his attention to the elaboration and perfection of the old process, in the working of which considerable improvements have been introduced within the last ten or fifteen years; improvements resulting not only in a diminished cost of production, but in the manufacture of a purer, and therefore better acid.

The proper construction of the furnaces, ovens, and grates on which the firing of the sulphur or pyrites takes place, together with the flues, is an important condition in the manufacture of the acid; and to this end a great deal of scientific knowledge and experience have lately been applied with excellent effect. Of the many improvements in this direction for burning poor ores of pyrites is a contrivance much used in Germany, where the furnace on which it is carried out is known as Gerstenhöfer’s oven. It is shown in the accompanying drawing.

The furnace is fitted inside with a number of little fire-clay projections, arranged as shown in the plate, in banks or terraces, the function of which is to prolong the exposure of the pyrites to heat. The furnace having been previously raised to a red heat, by means of a coal or wood fire (which is then extinguished), the pyrites are admitted into it through the hoppers (_a_). At the base of the hoppers are grooved iron rollers, which crush the lumps of ore as they enter the chambers, and by thus reducing their size, expose a larger amount of surface to the action of heat. The greater part of the sulphur of the pyrites is thus burnt off, as the lumps pass from terrace to terrace, the heat at the same time generated by their combustion being sufficient to keep up that of the furnace. A moderate blast of air is admitted at _c_, whilst the sulphurous acid formed ascends through _d_ into the leaden chambers, the spent pyrites falling out through the apertures at _c_.

Another improved furnace is Perret’s, which is largely used in France. In this, small lumps of pyrites are placed on horizontal plates, and exposed to the hot gases generated in kilns below. The gases, on their way to the chambers, sweep over the pyrites and rob them of their sulphur.

The most important and noticeable improvement, however, of late years in sulphuric acid manufacture is that resulting from the addition to the plant of a contrivance of Gay-Lussac. Previous to this invention, the sulphuric acid of commerce, amongst other impurities, always contained appreciable quantities of certain oxides of nitrogen, the results of which were not only the contamination of the acid, but a waste of substances, which, properly utilised, are essential for the conversion of the sulphurous and sulphuric acid, and the loss of which leads to an increased consumption of nitrate of soda. Under the old method, these valuable oxides of nitrogen, which, with a large amount of nitrogen and a small quantity of oxygen, constituted the spent air of the last leaden chamber, were carried off into the air, and consequently lost. Now, instead of being allowed to diffuse into the atmosphere, they are made to pass through a tower or chamber (shown at C in the plate below) filled with coke, through which a thin stream of sulphuric acid is made to trickle. In passing through the coke, therefore, the expiring spent gases come into contact with the sulphuric acid, to which they give up their oxides of nitrogen. From the tower (C) the acid flows into a cistern (D), whence it is pumped up to the top of another tower (E), either filled with coke, or arranged with inclined shelves, as shown in the plate. In this tower the acid meets with a current of hot sulphurous acid and air coming up from the furnace, which deprive it of the oxides of nitrogen, and the gaseous mixture enters the chambers, whilst the denitrafied acid flows off into a suitable reservoir.

Since the introduction of the above, the consumption of nitrate of soda is sometimes lessened by more than half.

Another very recent improvement, the invention of a German chemist named Sprengel, is the substitution of water spray, blown in by steam, for steam jets, in the leaden chambers. By this method a saving of coal to the extent of one third is said to be effected.

In theory, 1 molecule of sulphur requires only 3 molecules of oxygen to convert it into sulphuric acid, viz. 2 to form sulphurous anhydride, and 1 to convert the latter into sulphuric anhydride, which combines with 1 molecule of water to form the acid. Thus, 1 kilogram of sulphur requires 1500 grams or 1055 litres of oxygen, which is equivalent to 5275 litres of air containing 4220 litres of nitrogen; when pyrites is used, a far larger quantity of air is required, for the obvious reason that the pyrites becomes converted into ferric peroxide. 1 kilogram of pyrites requires for its combustion nearly 6600 litres of air.

In well-regulated works the spent and escaping gases should not contain more than 2 per cent. of oxygen. If from 100 kilograms of sulphur 306 kilograms of strong acid of sp. gr. 1·84 be obtained, the result is regarded as very satisfactory; more frequently the product from 100 kilograms of sulphur does not exceed 280 or 290 kilograms.

_Purif._ Commercial sulphuric acid frequently contains nitrous acid and other oxides of nitrogen, arsenic, lead, and saline matter. The nitrous acid may be removed by adding a little sulphate of ammonia, and heating the acid to ebullition for a few minutes. Both nitric and nitrous acid are thus entirely decomposed into water and nitrogen gas. The arsenic may be got rid of by adding a little sulphide of barium to the acid, agitating the mixture well, and, after repose, decanting and distilling it. Lead, which exists as sulphate, may be separated as a white precipitate by simply diluting the acid with water. Saline matter may be removed by simple rectification. A good way of purifying oil of vitriol is to heat it nearly to the boiling point, and pass a current of hydrochloric acid through it; the arsenic is thus carried over as the volatile chloride of arsenic, while the nitrous and nitric acids are expelled almost completely. To obtain a perfectly pure acid, it should be distilled after the removal of the nitrous acid and arsenic by the methods indicated above. “The distillation is most conveniently conducted, on the small scale, in a glass retort, containing a few platinum chips, and heated by a sand bath or gas-flame, rejecting the first 1/2 fl. oz. that comes over.” (Ph. E.) In the Ph. D. the first tenth of the distillate is ordered to be rejected, and the process to be stopped when no more than about 1 fl. oz. is left in the retort.

According to Dr Ure, the capacity of the retort should be from 4 to 8 times as great as the volume of the acid, and connected with a large tubular receiver by a loosely fitting glass tube, 4 feet long and 1 to 2 inches in diameter. “The receiver should not be surrounded with cold water.” We find that fragments of glass, or of rock crystals, may be advantageously substituted for platinum foil, to lessen the explosive violence of the ebullition. Sulphuric acid which has become brown by exposure may be decolorised by heating it gently, the carbon of the organic substances being thus converted into carbonic acid.

_Prop._ Commercial sulphuric acid (oil of vitriol) is a colourless, odourless, and highly corrosive liquid, the general properties of which are well known. Its sp. gr. at 60° should never be greater than 1·848, or less than 1·840. (Miller and Odling give the sp. gr. of the pure and concentrated acid as 1·842; Abel and Bloxam, as 1·848; Apjohn gives it as 1·846, and Hardwich about 1·845.) It is immediately coloured by contact with organic matter. It attracts water so rapidly from the atmosphere when freely exposed to it, as to absorb 1-3rd of its weight in 24 hours, and 6 times its weight in a few months. When 3 volumes are suddenly mixed with 2 of water, the temperature of the mixture rises more than 180° Fahr. Its freezing point appears to be about 60° below that of water (Miller and Odling give that of the rectified acid as -30° Fahr.; Apjohn and Abel and Bloxam, -29°). It boils at about 620° Fahr. (620·6°, Odling; 620°, Hardwich and Fownes; 617°, Apjohn; 590·6°, Abel and Bloxam). It exhibits all the properties of the acids in an exalted degree. Its salts are called sulphates.

In the following table is given the quantity of anhydrous sulphuric acid contained in sulphuric acid at 60°F. (15·5°C.).

+--------------------------------+----------------------------------+
|Hydrated Sp. Gr. Anhydrous | Hydrated Sp. Gr. Anhydrous |
|Sulphuric Acid. | Sulphuric Acid. |
|Acid. | Acid. |
| | |
| 100 1·8485 81·54 | 76 1·6630 61·97 |
| 99 1·8475 80·72 | 75 1·6520 61·15 |
| 98 1·8460 79·90 | 74 1·6415 60·34 |
| 97 1·8439 79·09 | 73 1·6321 59·55 |
| 96 1·8410 78·28 | 72 1·6204 58·71 |
| 95 1·8376 77·40 | 71 1·6090 57·89 |
| 94 1·8336 76·65 | 70 1·5975 57·08 |
| 93 1·8290 75·83 | 69 1·5868 56·26 |
| 92 1·8233 75·02 | 68 1·5760 55·45 |
| 91 1·8179 74·20 | 67 1·5648 54·63 |
| 90 1·8115 73·39 | 66 1·5503 53·82 |
| 89 1·8043 72·57 | 65 1·5390 53·00 |
| 88 1·7962 71·75 | 64 1·5280 52·18 |
| 87 1·7870 70·94 | 63 1·5170 51·37 |
| 86 1·7774 70·12 | 62 1·5066 50·55 |
| 85 1·7673 69·31 | 61 1·4960 49·74 |
| 84 1·7570 68·49 | 60 1·4860 48·92 |
| 83 1·7465 67·68 | 59 1·4760 48·11 |
| 82 1·7360 66·86 | 58 1·4660 47·29 |
| 81 1·7245 66·05 | 57 1·4560 46·58 |
| 80 1·7120 65·23 | 56 1·4460 45·68 |
| 79 1·6993 64·42 | 55 1·4360 44·85 |
| 78 1·6870 63·60 | 54 1·4265 45·03 |
| 77 1·6750 62·78 | 53 1·4170 43·22 |
+--------------------------------+----------------------------------+

_Pur._ “Free from colour and odour. Sp. gr. 1·843. 100 gr. are saturated by 285 gr. of crystallised carbonate of soda.” (Ph. L.) “What remains after the acid is distilled to dryness does not exceed 1/400th part of its weight. Diluted sulphuric acid is not discoloured by sulphuretted hydrogen.” (Ph. L. 1836.) “Diluted with its own volume of water, only a scanty muddiness arises, and no orange fumes escape. Sp. gr. 1·840.” (Ph. E.) “The rectified acid (ACIDUM SULPHURICUM PURUM——Ph. E. & D.) is colourless; dilution causes no muddiness; solution of sulphate of iron shows no reddening at the line of contact when poured over it. Sp. gr. 1·845.” (Ph. E.) Sp. gr. 1·846——Ph. D.; 1·843——B. P.; 1·842——Ure.

_Tests._——See SULPHATE.

_Uses, &c._ “The uses of sulphuric acid are so numerous that it would be impossible to mention all of them, sulphuric acid being to chemical industry what iron is to the mechanical. Sulphuric acid is employed in preparing a great many other acids——among them, nitric, hydrochloric, sulphurous, carbonic, tartaric, citric, phosphoric, stearic, oleic, and palmitic. Further, sulphuric acid is used in making superphosphates, soda, sulphate of ammonia, alum, sulphates of copper and iron, in paraffin and petroleum refining, silver refining, manufacture of garacine, garanceux, and other madder preparations, manufacture of glucose from starch, to dissolve indigo, &c.[216] In the diluted state it is used in medicine. When swallowed, it acts as a violent corrosive poison. The antidotes are chalk, whiting, magnesia, carbonate of soda, or carbonate of potash, mixed with water, or any bland diluent, and taken freely, an emetic being also administered.

[Footnote 216: Wagner.]

_Estim._ The strength of sulphuric acid is most correctly ascertained by its power of saturating bases. In commerce, it is usually determined from its sp. gr. The quantity of sulphuric acid present in a compound may be determined by weighing it under the form of sulphate, as explained in a former part of this volume. See ACIDIMETRY.

_Concluding Remarks._ According to most of our standard works on chemistry, British oil of vitriol, when purified and brought to its maximum strength by distillation, is a definite chemical compound, having the formula H_{2}SO_{4}, and designated normal sulphuric acid by Odling. Marignac, however, asserts that the distilled acid always contains an excess of water, and that the true monohydrate can only be obtained by submitting fuming sulphuric acid (‘Nordhausen s. a,’) to congelation. According to this chemist, the true monohydrate readily freezes in cold weather, and remains solid up to 51° Fahr. Two other definite hydrates of sulphuric acid are generally recognised by chemists, viz.——Bihydrated sulphuric acid (‘glacial s. a,’), having a sp. gr. of 1·78; freezing at about 40° Fahr. (47°, Miller); and boiling at about 435° (Apjohn; 401° to 410°, Odling): Terhydrated sulphuric acid, having a sp. gr. of 1·632, and the boiling-point 348° Fahr. See also SULPHURIC ACID, NORDHAUSEN (_below_).

=Sulphuric Acid, Al′coholised.= _Syn._ ACIDUM SULPHURICUM ALCOHOLISATUM, L.; EAU DE RABEL, Fr. _Prep._ (P. Cod.) To rectified spirit, 3 parts, add, very gradually, sulphuric acid, 1 part. It is generally coloured by letting it stand over a little cochineal. Refrigerent, and, externally, escharotic.——_Dose_, 1/2 fl. dr. to water, 1 pint; as a cooling drink in fevers, &c.

=Sulphuric Acid, Anhy′drous.= SO_{3}. _Syn._ SULPHURIC ANHYDRIDE, DRY SULPHURIC ACID; ACIDUM SULPHURICUM SINE AQUÂ, L. _Prep._ 1. By heating Nordhausen acid to about 100° Fahr. in a glass retort connected with a well-cooled receiver.

2. By distilling anhydrous bisulphate of soda, which has previously been raised to a low red heat in an earthen retort, to which a receiver is fitted without the aid of corks.

3. (Barreswill.) 2 parts of the strongest oil of vitriol are gradually added to 3 parts of anhydrous phosphoric acid, contained in a retort surrounded by a freezing mixture; when the compound has assumed a brown colour, the retort is removed from the bath, and connected with a receiver which is set there in its place; a gentle heat is now applied to it, when white vapours pass over into the receiver, and condense there under the form of beautiful silky crystals. The product equals in weight that of the phosphorus originally employed. “If a few drops of water be added, a dangerous explosion ensues.”

_Prop._ White, silky, asbestos-like crystals, deliquescing rapidly, and fuming in the air; put into water, it hisses like a red-hot iron; it melts at 77°, and rapidly volatilises at 86° Fahr.; it does not redden dry litmus paper; sp. gr. 1·97 at 78° Fahr.

=Sulphuric Acid, Aromat′ic.= _Syn._ ELIXIR OF VITRIOL, ACID E. OF V.; ACIDUM SULPHURICUM AROMATICUM (B. P., Ph. E. & D.), L. _Prep._ 1. (Ph. E. & D.) Oil of vitriol, 3-1/2 fl. oz.; rectified spirit, 1-1/2 pint; mix, add of powdered cinnamon, 1-1/2 oz.; powdered ginger, 1 oz.; digest for 6 days (7 days——Ph. D.), and filter. Sp. gr. ·974——Ph. D.

2. (Wholesale.) From compound tincture of cinnamon, 1 gall.; oil of vitriol, 1 lb.; mix, and in a week filter——_Dose_, 10 to 30 drops, in the same case as the dilute acid.

3. (B. P.) Sulphuric acid, 3; rectified spirit, 40; cinnamon, in powder, 2; ginger, in powder, 1-1/4; mix the acid gradually with the spirit, add the powders, macerate for 7 days, and filter.——_Dose_, 5 to 30 minims.

=Sulphuric Acid, Dilute′.= _Syn._ SPIRIT OF VITRIOL; ACIDUM SULPHURICUM DILUTUM (B. P., Ph. L., E., & D.), L. _Prep._ 1. (Ph. L.) Take of sulphuric acid, 15 fl. dr., and dilute it gradually with distilled water, q. s. to make the whole exactly measure a pint. Sp. gr. 1·103. “1 fl. oz. of this acid is exactly saturated by 216 gr. of crystallised carbonate of soda.”

2. (Ph. E.) Sulphuric acid, 1 fl. oz.; water, 13 fl. oz. Sp. gr. 1·090.

3. (Ph. D.) Pure sulphuric acid, 1 fl. oz.; distilled water, 13 oz. Sp. gr. 1·084.

4. (B. P.) Sulphuric acid, 3; distilled water, q. s. to measure 35-3/4; mix by adding the acid gradually to the water.——_Dose_, 4 to 20 minims.

_Prop., &c._ Antiseptic, tonic, and refrigerant.——_Dose_, 10 to 30 drops, largely diluted with water, several times daily; in low typhoid fevers, passive hæmorrhages, profuse perspiration, in various skin diseases to relieve the itching, in dyspepsia, &c. It is also used externally.

=Sulphuric Acid, Nordhausen.= _Syn._ FUMING SULPHURIC ACID; ACIDUM SULPHURICUM FUMANS, L. _Prep._ By distilling calcined ferrous sulphate (‘green vitriol’) in earthen retorts. The retorts, which are shown at A in the plate after the ‘green vitriol’ has been put into them, are placed in a galley-furnace, as shown below, the necks passing through the wall of the furnace, and being properly secured to the necks of the receivers (B B.). Into each of the flasks 2-1/2 lbs. of green vitriol are put; on the first application of heat only sulphurous acid and weak hydrated sulphuric acid come over, and are usually allowed to escape, the receivers not being securely luted until white vapours of anhydrous sulphuric acid are seen. Into each of the receiving flasks 30 grams of water are poured, and the distillation continued for 24 to 36 hours. The retort flasks are then again filled with raw material, and the operation repeated four times before the oil of vitriol is deemed strong enough. The residue in the retorts is red (peroxide) of iron, still retaining some sulphuric acid. The product is a brown oily liquid, which fumes in the air, is intensely corrosive, and has a sp. gr. about 1·900. When heated to about 100° Fahr. the anhydrous acid is given off, and ordinary oil of vitriol is left. According to Marignac, crystals of normal sulphuric acid (H_{2}SO_{4}) are formed in this acid when it is submitted to a low temperature. Nordhausen acid is so called from the place of its manufacture in Saxony. It may be regarded as a mixture or compound of H_{2}SO_{4} and SO_{2}. It is chiefly used for dissolving indigo.

=SULPHURIC ANHYDRIDE.= See SULPHURIC ACID, ANHYDROUS.

=SULPHURIC E′THER.= See ETHER.

=SUL′PHUROUS ACID.= SO_{2}. _Syn._ SULPHURUS ANHYDRIDE; ACIDUM SULPHUROSUM, B. P. This compound is freely evolved in the gaseous form when sulphur is burnt in air or oxygen, and when the metals are digested in hot sulphuric acid; and, mixed with carbonic acid, when charcoal, chips of wood, cork, and sawdust, are treated in the same way.

_Prep._ 1. By heating together sulphur and strong sulphuric acid.

2. By the action of sulphuric acid on chippings of copper or mercury at a gentle heat. Pure.

3. (Berthier.) By heating, in a glass retort, a mixture of black oxide of manganese, 100 parts, and sulphur, 12 or 14 parts. Pure. The gas evolved should be collected over mercury, or received into water.

4. (Redwood.) Pounded charcoal, 1/2 oz.; oil of vitriol, 4 fl. oz.; mix in a retort, apply the heat of a spirit lamp, and conduct the evolved gases by means of a bent tube into a bottle containing water. The sulphurous acid is absorbed, whilst the carbonic acid gas passes off.

5. (B. P.) Distilled water, saturated with sulphurous anhydride. It is colourless and emits a pungent odour. Used as a deoxidiser, disinfectant, and antiseptic. Diluted with from 1 to 2 parts of water it is employed as a lotion for wounds, cuts, ulcers, bed-sores, scalds, and burns; with from 1 to 5 of water it is used as a gargle, also as a lotion in parasitic skin diseases; from 1/2 to 1 dr., in a wine-glassful of water, 3 times a day, relieves constant sickness.

_Prop., &c._ Water absorbs 30 times its volume of this gas. Pure liquid sulphurous acid can only be obtained by passing the pure dry gas through a glass tube surrounded by a powerful freezing mixture. Its sp. gr. is 1·45; boiling point, 14° Fahr.; it causes intense cold by its evaporation. Sulphurous acid forms salts called sulphites.

_Uses._ To bleach silks, woollens, straw, &c., and to remove vegetable stains and iron-moulds from linen. For these purposes it is prepared from sawdust or any other refuse carbonaceous matter.

Several preparations containing sulphurous acid have recently been invented by the Editor and introduced to the public as agents in sanitation under the name of _Sporokton_ (germ-killer). To understand the nature and merits of these preparations it is desirable to explain the true and individual meanings of ‘Deodoriser,’ ‘Antiseptic,’ and ‘Disinfectant,’——words which are too often improperly employed as if they had the same signification, and as if, in fact, they were convertible terms.

A deodoriser is a substance which will absorb or destroy bad smells; an antiseptic is an agent which will prevent or retard putrefaction; and a disinfectant is an agent which will render harmless the virus of smallpox, scarlet fever, measles, diphtheria, influenza, pleuro-pneumonia, cattle plague, glanders, distemper in dogs, and other infectious or contagious diseases.

Now, medical authorities and sanitarians are of opinion that the most potent disinfectant with which we are acquainted is sulphurous acid, a gas which has been used for ages, as a fumigator. Sulphurous acid has not, however, been so generally employed for disinfecting purposes as one might from these circumstances have expected, on account of the difficulties and inconveniences which formerly attended its generation.

To remove these drawbacks, and to render sulphurous acid, both as a gas and in solution, easily and cheaply available for the above-named and many other applications, sporokton has been invented. Several varieties are made; they are as follows:

_Liquid No. 1._——This preparation consists of a colourless solution of a non-volatile antiseptic, usually a salt of zinc, impregnated with eighty times its bulk of sulphurous acid gas; in other words, one pint of the liquid contains ten gallons of gas. Liquid sporokton is, in fact, a combination of one of the most powerful antiseptics with the disinfectant; the former ingredient will effectually prevent the putrefaction of any solid or liquid animal or vegetable matter with which it may come in contact, while the sulphurous acid will rapidly pass off in the gaseous state into the surrounding air and act as an energetic destroyer of noxious atmospheric impurities.

Liquid sporokton absorbs ammonia and sulphuretted hydrogen, destroys bad smells, and prevents the spread of infectious diseases; it is, consequently, a valuable agent for the deodorisation and disinfection of wards of hospitals, sick rooms, dairies, larders, ship, stables, cow-houses, kennels, piggeries, slaughter-houses, urinals, water-closets, privies, cesspools, sewers, drains, and other similar buildings and places.

After it has parted with the whole of its sulphurous acid gas, liquid sporokton leaves an odourless, non-volatile antiseptic and absorber of ammonia and sulphuretted hydrogen.

Liquid sporokton evolves its sulphurous acid by simple exposure to air, without the aid of heat, so that no risk of fire attends its use, as is the case when rooms, buildings, holds of ships, &c., are fumigated with this gas by the old plan; it will not stain or in any other way injure undyed woollen, linen, or cotton goods. It is consequently well adapted for the disinfection of underclothing, sheets, blankets, bed-furniture, &c.

Liquid sporokton may be employed for the instantaneous preparation of a bath or lotion of sulphurous acid, to be used, under medical direction, in the treatment of itch, ringworm, chronic eczema, lepra, psoriasis, impetigo, pityriasis, &c., in man, as well as mange, scab, and other skin affections in the lower animals.

Liquid sporokton is clean, it requires no skill in using it, and its action is perfectly controllable.

_Liquid, No. 2._——This preparation is specially made for the disinfection and purification of old beer barrels, wine casks, and the like. It is similar in composition to, and may be used for the same purpose as No. 1; except, however, that as No. 2, unlike No. 1, is liable, from its containing iron instead of zinc, to stain linen, wood, &c., it should not be employed for disinfecting clothing or sprinkling over floors, decks of ships, and the like.

_Solid._——This is a powder, usually a mixture of calcium sulphite and ferric chloride, which, by simple expose to air, will slowly and steadily, or when sprinkled with water, rapidly give out 25 per cent. of its weight of sulphurous acid and leave no unpleasant smell behind it.

Sulphurous acid gas, unlike non-volatile disinfectants, quickly mingles with the air, and seeks out, as it were, the noxious atmospheric impurities it is capable of destroying.

Solid sporokton, in addition to evolving sulphurous acid, contains an excess of ferric chloride which, together with this gas, renders it a most useful and efficient antiseptic.

=Sulphurous Anhydride.= See SULPHUROUS ACID.

=SU′MACH.= This dye stuff is chiefly used as a substitute for galls. With a mordant of acetate of iron, it gives grey or black; with tin or acetate of alumina, yellow; and with sulphate of zinc, a yellowish-brown; alone, it gives a greenish-fawn colour.

=SUM′BUL.= _Syn._ MUSK ROOT, JATAMANSI, SUMBUL ROOT; SUMBUL RADIX (B. P.). A substance introduced to British medicine by Dr A. B. Granville, in 1850. It occurs in circular pieces, varying from 1 to 3 or 4 inches in diameter; has a musk-like odour, and a sweet balsamic taste. It acts as a powerful stimulant, especially of the nervous system. In India and Persia it has long been used as a medicine, a perfume, and as incense.——_Dose_, 15 gr. to 1 dr., either masticated, or made into an infusion, electuary, or tincture; in cholera, hysteria, neuralgia, epilepsy, low fevers, and various other spasmodic and nervous disorders.

=SUMMER DRINKS.= See LEMONADE, SHERBET, &c.

=SU′PER-.= See NOMENCLATURE.

=SUP′PER.= The evening meal; the last meal of the day. Supper is generally an unnecessary meal, and, when either heavy, or taken at a period not long before that of retiring to rest, proves nearly always injurious, preventing sound and refreshing sleep, and occasioning unpleasant dreams, nightmare, biliousness, and all the worst symptoms of imperfect digestion. The last meal of the day should be taken at least three hours before bedtime. Even when it consists of some ‘trifle,’ as a sandwich or biscuit, an interval of at least an hour should elapse before retiring to rest. In this way restlessness and unpleasant dreams will become rare.

=SUPPOS′ITORY.= _Syn._ SUPPOSITORIUM, L. A medicine placed in the rectum for the purpose of affecting the lower intestine, or, by absorption, the system generally. Suppositories are rounded, usually elongated masses, having the active medicine combined with some substance which will retain the proper shape, as soap, spermaceti cerate, or cacao-butter. The latter substance is, perhaps, the best vehicle for remedies prescribed in this form. It is, however, rather too soft to be used without admixture. According to Dorvault, the addition of one eighth part by weight of wax imparts the proper hardness.

All difficulty of removing suppositories from the mould may be obviated by having the moulds previously dusted with lycopodium.

The mode of proportioning the doses of active ingredients has been noticed in the article ENEMA.

=Suppository, Astringent.= _Syn._ SUPPOSITORIUM ASTRINGENS (Reuss). _Prep._ Powdered oak bark, 2 dr.; tormentil, 2 dr.; honey, q. s. For 8 suppositories.

=Suppository of Carbolic Acid.= _Syn._ SUPPOSITORIUM ACIDI CARBOLICI (Ph. U. S.). _Prep._ Carbolic acid, 12 gr.; oil of theobroma, 348 gr.; water, q. s. Dissolve the acid in a few drops of water, and mix it with 1 dr. of oil of theobroma; then add it to the remainder of the theobroma previously melted, and cooled to the temperature of 95° F., and pour the whole immediately into moulds of 30 gr. each, standing in iced water.

=Suppository of Copaiba.= _Syn._ SUPPOSITORIUM COPAIBA (Colombat). _Prep._ Solidified copaiba, 1 dr.; butter of cacao, 1 dr.; extract of opium, 1/2 gr.

=Suppository of Elaterium.= _Syn._ SUPPOSITORIUM ELATERII (St B. H.). _Prep._ Extract of elaterium, 2 gr.; hard soap, 10 gr.; water, q. s. Mix.

=Suppository, Emollient.= _Syn._ SUPPOSITORIUM EMOLLIENS. _Prep._ Butter of cacao and spermaceti in equal parts; melted together.

=Suppository of Iodide of Potassium.= _Syn._ SUPPOSITORIUM POTASSII IODIDII (Mr Stafford). _Prep._ Iodide of potassium, 1 gr. to 4 gr.; extract of henbane, 6 gr.; extract of hemlock, 6 gr. In enlarged prostate.

=Suppository, Irritant.= _Syn._ SUPPOSITORIUM IRRITANS (Richard). _Prep._ Butter of cacao, 2 dr.; aloes, 4 gr.; tartarised antimony, 1 gr. To restore the hæmorrhoidal flux.

=Suppository of Lead (Compound).= _Syn._ SUPPOSITORIUM PLUMBI COMPOSITUM (B. P.). _Prep._ Acetate of lead, in powder, 36; opium, in powder, 12; benzoated lard, 42; white wax, 10; oil of theobroma, 80; melt the wax and oil of theobroma with a gentle heat, then add the other ingredients, previously rubbed together in a mortar, and, having mixed them thoroughly, pour the mixture while it is fluid into suitable moulds of the capacity of 15 gr. The above makes 12 suppositories.

=Suppository of Mercury.= _Syn._ SUPPOSITORIUM HYDRARGYRI (B. P.). _Prep._ Ointment of mercury, 60 gr.; benzoated lard, 20 gr.; white wax, 20 gr.; oil of theobroma, 80 gr.; melt all but the mercurial ointment together, then add the ointment of mercury, stir till well mixed, and immediately pour into moulds of the capacity of 15 gr. The above makes 12 suppositories.

=Suppository of Morphia.= _Syn._ SUPPOSITORIUM MORPHIÆ (B. P.). _Prep._ Hydrochlorate of morphia, 6 gr.; oil of theobroma, 90 gr.; benzoated lard, 64 gr.; white wax, 20 gr.; melt the wax and oil of theobroma with a gentle heat, then add the hydrochlorate of morphia and benzoated lard, previously rubbed together in a mortar, and mix all the ingredients thoroughly; pour the mixture, while it is fluid, into suitable moulds of the capacity of 15 gr., or the fluid mixture may be allowed to cool, and then be divided into 12 equal parts, each of which should be made into a conical form.

=Suppository of Opium.= _Syn._ SUPPOSITORIUM OPII (Ph. U. S.). _Prep._ Extract of opium, 12 gr.; oil of theobroma, 348 gr.; water, q. s. Proceed as for carbolic acid suppository.

=Suppository for Piles.= _Syn._ SUPPOSITORIUM HÆMORRHOIDALE, S. SEDATIVUM, L. _Prep._ 1. Powdered opium, 2 gr.; finely powdered galls, 10 gr.; spermaceti cerate, 1 dr.

2. (Ellis.) Powdered opium, 2 gr.; soap, 10 gr.; mix.

3. (Richard.) Extracts of opium and stramonium, of each 1 gr.; cacao-butter, 2 dr. Used when the piles are very painful.

=Suppository, Pur′gative.= _Syn._ SUPPOSITORIUM CATHARTICUM, L. _Prep._ 1. Soap, 1 dr.; elaterium, 1 to 2 gr.; mix. As a strong purge.

2. (Niemann.) Soap, 2 dr.; common salt, 1 dr.; honey, q. s.; mix. As a mild cathartic.

=Suppository of Quinine.= _Syn._ SUPPOSITORIUM QUINÆ (Boudin). _Prep._ Sulphate of quinine, 15 gr.; butter of cacao, 1-1/2 dr. Mix.

=Suppository, Resol′vent.= _Syn._ SUPPOSITORIUM RESOLVENS, L. _Prep._ (Stafford.) Iodide of potassium, 3 to 4 gr.; extracts of henbane and hemlock, of each 6 gr. In enlargement or induration of the prostate gland.

=Suppository of Rhatany.= _Syn._ SUPPOSITORIUM RHATANIÆ (P. Cod). _Prep._ Butter of cacao, 1 dr.; extract of rhatany, 15 gr., for 1 suppository.

=Suppository, Sed′ative.= See _above_.

=Suppository of Sulphate of Soda.= _Syn._ SUPPOSITORIUM SODÆ SULPHATIS (Phœbus). _Prep._ Dried sulphate of soda, 2 dr.; powdered soap, 4 dr.; honey, q. s. For 4 suppositories. To be smeared over with oil when applied.

=Suppository of Tannic Acid.= _Syn._ SUPPOSITORIUM ACIDI TANNICI (B. P.). _Prep._ Tannic acid, 36 gr.; benzoated lard, 44 gr.; white wax, 10 gr.; oil of theobroma, 90 gr.; melt the wax and oil with a gentle heat, then add the tannic acid and benzoated lard, previously rubbed together, and mix thoroughly. Pour the mixture while it is fluid into suitable moulds of the capacity of 15 gr. The above makes 12 suppositories.

=Suppository, Ver′mifuge.= _Syn._ SUPPOSITORIUM ANTHELMINTICUM, S. VERMIFUGUM, L. _Prep._ (Swediaur.) Aloes, 4 dr.; common salt, 3 dr.; flour, 2 dr.; honey, q. s. to make a stiff mass; divide into proper-shaped pieces, weighing about 15 gr. each. One to be used after each motion.

=Suppositories of Aloes.= _Syn._ SUPPOSITORIA ALOES (B. P.). _Prep._ Aloes in fine powder. 1 dr.; oil of theobroma, 300 gr. Proceed as for carbolic acid suppository, omitting the water.

=Suppositories of Assafœtida.= _Syn._ SUPPOSITORIA ASSAFŒTIDÆ (Ph. U. S.). _Prep._ Tincture of assafœtida, 1 oz.; oil of theobroma, 320 gr. Let the tincture evaporate by exposure to the air until of the consistence of a thick syrup, and proceed as for suppositories of carbolic acid.

=Suppositories of Belladonna.= _Syn._ SUPPOSITORIA BELLADONNÆ (Ph. U. S.). _Prep._ Alcoholic extract of belladonna, 6 gr.; oil of theobroma, 354 gr. Proceed as for carbolic acid suppositories.

=Suppositories of Carbolic Acid with Soap.= _Syn._ SUPPOSITORIA ACIDI CARBOLICI CUM SAPONE (B. P.). _Prep._ Carbolic acid, 12 gr.; curd soap, in powder, 180 gr.; starch, q. s.; mix the carbolic acid with the soap, and add starch, q. s., to make of a suitable consistency; divide into 12 equal parts, and make each suppository into a conical or other convenient form.

=Suppositories of Colocynth.= _Syn._ SUPPOSITORIA COLOCYNTHIDIS (Sp. Ph.). _Prep._ Colocynth, 30 gr.; salt, 1 dr. Evaporate to a due consistence.

=Suppositories of Morphia with Soap.= _Syn._ SUPPOSITORIA MORPHIÆ CUM SAPONE (B. P.). _Prep._ Hydrochlorate of morphia, 6 gr.; glycerin of starch, 50 gr.; curd soap in powder, 100 gr.; starch, q. s. Mix the hydrochlorate with the glycerin of starch and soap, and add starch q. s. to form a paste of suitable consistence. Divide into 12 equal parts, each of which is to be made into a conical or other convenient form of suppository.

=Suppositories of Tannic Acid with Soap.= _Syn._ SUPPOSITORIA ACIDI TANNICI CUM SAPONE (B. P.). _Prep._ Tannic acid, 36 gr.; glycerin of starch, 50 gr.; curd soap in powder, 100 gr.; starch, q. s. Mix the tannic acid with the glycerin of starch and soap, and add starch q. s. to form a paste of suitable consistence, divide into 12 equal parts, each of which is to be made into a conical or other convenient form of suppository.

=Suppositories, Vaginal.= _Syn._ SUPPOSITORIA VAGINALE (Guadrist). _Prep._ Liquid chloride of zinc, 5 minims; sulphate of morphia, 1/2 gr.; mix with 2 dr. of the following paste:——Thick mucilage of tragacanth, 6 parts; white sugar, 3 parts; starch, 9 parts. Mr Druitt prescribes in leucorrhœa:——Tannin, 10 gr., with mucilage of tragacanth, q. s.

=SURGERY.= “This word,” says Brande, “in its modern acceptation, may be defined as the practical application of science, in the use of all mechanical and instrumental means, for the removal of diseases and the relief of human suffering.”

One of the earliest professors of the ancient art of surgery, of whom history affords a reliable record, was Hippocrates, a Greek, who lived in the fifth century of our era, and who seems to have been a man of considerable skill for the period in which he flourished, since he could set fractures, reduce dislocations, and perform other important operations. About two centuries after Hippocrates the studies of surgery, anatomy, and medicine were prosecuted with evident success at Alexandria. The Alexandrian school produced some able surgeons, one of whom, Ammianus, invented an instrument for crushing the stone in the bladder, and was thus the first to practise the now important surgical operation known as lithotrity. At the beginning of the Christian era Celsus practised the art of surgery in Rome; he appears to have been the first to operate for cataract, and to apply ligatures to arteries after operations. It is curious to note that so practical a people as the Romans held the art of surgery in comparative contempt, and banished its professors, whose services they discarded, for the practice of spells, incantations, and charms.

In the sixth century lived Œtius, who conceived the idea of dissolving urinary calculi by the administration of internal remedies; and in the tenth, Avicenna, who, it has been conjectured, invented the flexible catheter, and was the inventor of the instrument now known as Hey’s saw. In 1271 the Paris College of Surgeons was founded, and the College of Surgeons of London in 1460, and the Edinburgh College in 1505.

The most prominent figure in the annals of surgery of the 16th century was Paré, a man of great originality of thought, whose works exercised a considerable influence over his own contemporaries, and for many years subsequently. Towards the end of the 17th century lived Wiseman, serjeant surgeon to Charles II. Wiseman was a man of considerable ability, and was the first to demonstrate that gun-shot wounds were not of a poisonous nature; and that therefore the old practice of applying painful and caustic dressings to them might most advantageously be abandoned. A contemporary of Wiseman was Young, of Plymouth, who merits notice as being the first who performed the flap-operation in amputation.

In the 17th century also lived Frère St Cosme, a French monk, who obtained considerable fame as an operator for lithotomy, for the performance of which he regarded himself as especially chosen by Heaven. In the 18th century lived in England Cheselden and Douglas, two eminent lithotomists; John Hunter, Pott and Ley; in Scotland, Benjamin and John Bell and Monro; and in Ireland, O’Halloran and Deases; whilst in France flourished Petit, celebrated for his treatise on diseases of the bones; from Germany, Rechter and Haller.

In this century (1784) was founded the Royal College of Surgeons in Ireland. In the present century there are few branches of science in which greater progress has been made than that of surgery. From amongst the most eminent of the English surgeons of the present century we may select the following names:——Abernethy, Blizard, Astley Cooper, Brodie, Dalrymple, Guthrie, Aston Key, Liston, Stanley, Travers, Arnott, Bowman, Erichsen, Fergusson, Prescott Hewett, Hilton, Lane, Lawrence, Paget, Spencer Wells, Marshall, Christopher Heath, Durham, Bryant, Nunn, Lee, H. Smith, Mason, and Pollock.

=SUSPENDED ANIMATION.= See ASPHYXIA.

=SWAL′LOW.= Three or four species of _hirundo_ (Linn.) pass under this name. It was once held in great repute in medicine. Even the excrement was included among the simples of the Ph. L. 1618. The swallow is an insectivorous bird, but, like the sparrow and rook, is much persecuted for its good services. It has been calculated that, directly and indirectly, a single swallow is the humble means of lessening the race of one kind of insect alone to the extent of 560,970,489,000,000,000 of its race in one year.

=SWEEPING.= Before commencing to sweep, the floor should be strewed with a good amount of damp tea-leaves, saved for the purpose; these collect the dust and thereby save the furniture, which as far as practicable should be covered up during the process. Tea-leaves may also be advantageously used upon druggets and short-piled carpets. Light sweeping and soft brooms are desirable if these latter are to be operated upon. Many a carpet is prematurely worn out by over-violent sweeping.

In sweeping thick-piled carpets, such as Axminster and Turkey carpets, the servant should always be instructed to brush the way of the pile; by following this advice the carpets may be kept clean for years; but if the broom is used in a contrary direction, all the dust will be forced into the carpet, and soon spoil it.

=SWEET BALLS.= _Prep._ Take of Florentine orris root, 3 oz.; cassia, 1 oz.; cloves, rhodium wood, and lavender flowers, of each 1/2 oz.; ambergris and musk, of each 6 gr.; oil of verbena, 10 or 12 drops; beat them to a paste, form this into balls with mucilage of gum tragacanth made with rose water, pierce them, whilst soft, with a needle, and, when they are quite dry and hard, polish them. Worn in the pocket as a perfume. Some persons varnish them, but that keeps in the smell.

=SWEET BAY.= _Syn._ LAUREL; LAURUS NOBILIS (Linn.), L. The fruit (LAURI BACCÆ; LAURUS——Ph. L.), as well as the leaves (LAURI FOLIA), are reputed aromatic, stimulant, and narcotic. They were formerly very popular in coughs, colic, hysteria, suppressions, &c.; and externally, in sprains, bruises, &c.

=SWEET′BREAD.= The thymus gland of the calf. When boiled, it is light and digestible; but when highly dressed and seasoned it is improper both for dyspeptics and invalids. (Pereira.)

=SWEET FLAG.= _Syn._ ACORUS CALAMUS, L. A plant of the natural order _Orontiaceæ_. The rhizome (‘root’) is an aromatic stimulant, and is regarded by some as a valuable medicine in agues, and as a useful adjunct to other stimulants and bitter tonics. It is sometimes employed by the rectifiers of gin. The volatile oil obtained from it by distillation is employed for scenting snuff and in the preparation of aromatic vinegar.

=SWEET′MEATS.= Under this head are properly included confections, candies, and preserves, in sugar; but, as generally employed, the word embraces all the sweet compounds of the confectioner.

Sweetmeats, as well as cakes, blancmange, and jellies, are not unfrequently coloured with deleterious substances, the consequences of which are always pernicious, and in many instances have proved fatal. Gamboge, a drastic cathartic; chrome yellow, red lead, orpiment, emerald green, and various other pigments containing lead, arsenic, copper, or other poisons, have been thus employed. The whole of these may be readily detected by the tests and characteristics appended to their respective names.

The colours and stains which may be safely employed to increase the beauty of these articles are noticed under STAINS and LIQUEUR.

=SWEETS.= Home-made wines: British wines.

=SWINE-POX.= See POX.

=SYDENHAM’S LEN′ITIVE.= _Prep._ Take of rhubarb (recently grated or powdered), 3 dr.; tamarinds, 2 oz.; senna, 1/2 oz.; coriander seeds (bruised), 2 dr.; boiling water, 1 pint; macerate for 3 hours in a covered vessel, and strain. An excellent stomachic and laxative.——_Dose_, 1/2 to 1 wine-glassful.

=SYL′VIC ACID.= _Syn._ SILVIC ACID. The portion of common resin or colophony which is the least soluble in cold and somewhat dilute alcohol.

=SYMBOLS.= In chemistry are representations of one atom of each of the elementary bodies, by the capital initial letter with or without the addition of a small letter of their Latin names. As C, for _carbon_; Fe (_ferrum_), iron; O, _oxygen_, &c.

Symbols, Alchemical[217]——

[Footnote 217: This list of alchemical and botanical symbols and abbreviations is a reprint of that contained in the ‘Lexicon of Terms used in Medicine and the Allied Sciences,’ now being published by the New Sydenham Society, under the Editorship of Henry Power, M.B., and Leonard W. Sedgwick, M.D.]

Acetum [symbol]
Acetum destillatum [symbol]
Acidum [symbol]
Aër [symbol]
Aerugo [symbol]
Alumen [symbol]
Alembic [symbol]
Æther [symbol]
Amalgama [symbol]
Ammonium [symbol]
Aqua [symbol]
Aqua fortis [symbol]
Aqua pluvialis [symbol]
Aqua regia [symbol]
Arena [symbol]
Argentum [symbol]
Arsenicum [symbol]
Auripigmentum [symbol]
Aurum [symbol]
Aurantium [symbol]
Baln. arenæ [symbol]
Baln. mariæ [symbol]
Baln. vaporis [symbol]
Baryta [symbol]
Bismuth [symbol]
Borax [symbol]
Calcaria [symbol]
Calcaria usta [symbol]
Camphora [symbol]
Cancer [symbol]
Caput mortuum [symbol]
Carbo [symbol]
Carbonicum [symbol]
Carduus benedictus [symbol]
Card. marianus [symbol]
Cera [symbol]
Cinis clavelatum [symbol]
Cinis [symbol]
Cinnabar [symbol]
Cornu cervi [symbol]
Cristalli [symbol]
Crucibulum [symbol]
Cuprum [symbol]
Distillare [symbol]
Ferrum [symbol]
Fictile [symbol]
Fixum [symbol]
Flores [symbol]
Gummi [symbol]
Hora [symbol]
Hydrargyrum [symbol]
Hydr. chloridum [symbol]
Hydr. corrosivum [symbol]
Ignis [symbol]
Kali [symbol]
Lapis [symbol]
Lithargyrum [symbol]
Magnet [symbol]
Magnesia [symbol]
Menstruum [symbol]
Natrum [symbol]
Nitrum [symbol]
Oleum [symbol]
Oxidatum [symbol]
Oxidulatum [symbol]
Per deliquium [symbol]
Plumbum [symbol]
Precipitare [symbol]
Preparare [symbol]
Pulvis [symbol]
Regulus [symbol]
Resina [symbol]
Retorta [symbol]
Saccharum [symbol]
Sal [symbol]
Sal kali [symbol]
Sal ammoniac [symbol]
Sal medius [symbol]
Sapo [symbol]
Spiritus [symbol]
Spiritus vini [symbol]
Spiritus rectificatissimus [symbol]
Spiritus rectificatus [symbol]
Stannum [symbol]
Stibium [symbol]
Stratum super stratum [symbol]
Sublimare [symbol]
Succinum [symbol]
Sulphur [symbol]
Tartarus [symbol]
Terra [symbol]
Terra foliata [symbol]
Tinctura [symbol]
Vitriolum [symbol]
Vitrum [symbol]
Volatile [symbol]
Urina [symbol]
Ustare [symbol]
Zincum [symbol]

=Symbols and Abbreviations, Botanical.=

[symbol] _Monocarp._ A plant which produces
seed only once during its life. The
symbol representing the sun.

=A=, [symbol] _Annual._ A monocarp which dies in
the same year that it germinated,
e.g. _Mustard_.

=B=, [symbol] _Biennial._ A monocarp which produces
leaves _only_ the first year and
perfects its seed the next, e.g. _Mullein_.

=P= _Perennial._ A plant which produces
seed for an indefinite number of
years, e.g. _Apple_.

[symbol] _Rhizocarp._ A perennial the stems
of which die down to the ground
every year, e.g. _Rhubarb_, _Mint_.
The symbol representing Jupiter,
which has a period of revolution
round the sun of 12 years.

[symbol] _Caulocarp._ A perennial, the stems
of which are persistent throughout
the whole of its life, e.g. _Apple_.
The symbol representing Saturn,
the period of revolution of which
round the sun is 30 years.

=H= _Herb._ A plant, the stems of which
remain soft or succulent, e.g. _Mint_
or _Rhubarb_.

=S=, [symbol] _Shrub._ A plant in which the stems
are woody, and which usually divide
near the ground into numerous
branches and twigs, e.g. _Lilac_.

[symbol] _Under shrub._ A small shrub; one
that does not grow more than 3 feet
in height, e.g. _Gooseberry_.

=T=, [symbol] _Tree._ A plant which grows to 20 feet
or more in height, having a woody
stem forming a distinct trunk, e.g.
_Oak_.

[symbol] A climbing plant which follows the
sun, e.g. _Hop_.

[symbol] A climbing plant which moves against
the sun, e.g. _Scarlet-runner_.

[symbol] Flowers having stamens only (unisexual,
staminiferous, or male),
e.g. male flowers of _Box_. The symbol
representing Mars, the period
of revolution of which is 2 years.

[symbol] Flowers having pistils only (unisexual,
pistillate, or female), e.g.
female flowers of _Box_. The symbol
representing Venus.

[symbol] Flowers having both stamens and
pistils (bisexual or hermaphrodite),
e.g. _Buttercup_.

[symbol] Abortive staminiferous flowers (neuter).

[symbol] Abortive pistillate flowers (neuter),
e.g. the florets of the ray in _Daisy_.

[symbol] Monœcious plants, producing male
and female flowers upon the same
individual, e.g. _Box_.

[symbol] Diœcious plants, producing male and
female flowers, but upon separate
individuals, e.g. _Willow_.

[symbol] Polygamous plants, which produce
hermaphrodite and unisexual flowers
upon the same or different individuals,
e.g. _Atriplex_.

[symbol] Indefinite in number; applied to
stamens and other parts of flowers.

[symbol] Cotyledons accumbent, radicle lateral.

[symbol] Cotyledons incumbent, radicle dorsal.

[symbol] Cotyledons conduplicate, radicle dorsal.

[symbol] Cotyledons twice folded, radicle dorsal.

[symbol] Cotyledons thrice folded, radicle dorsal.

[symbol] Trimerous, applied to flowers when
the whorls of the flower are multiples
of three, as in most endogens.

[symbol] Pentamerous, applied to flowers when
the whorls of the flower are multiples
of five, as in exogens generally.