Cooley's Cyclopaedia of Practical Receipts Volume I Part 220

[Footnote 285: 'Pharm. Journal,' February 5th, 1876.]

[Ill.u.s.tration: EUCALYPTUS GLOBULUS (from the 'Archiv der Pharm.,' 1873, p.

129.)]

The _Eucalyptus globulus_ is a very rapidly-growing tree, and attains to great proportions. "In some cases it has been known to attain the colossal dimensions of 350 feet in height and a 100 in circ.u.mference."[286]

[Footnote 286: Bentley.]

This magnitude is entirely out of proportion to the size of the seed, which is very minute; so minute that it has been computed one pound weight of the seed could produce 162,000 trees. Various preparations of the leaves and bark of the eucalypti have been introduced into medicine, which will be found under the respective pharmaceutical preparations. They were a.s.serted to be specially serviceable in intermittent fevers and bronchitis. The idea that their efficacy in the former cla.s.s of disease was due to the presence in the barks of the eucalypti of an alkaloid similar to, if not the same as, quinine, has been shown to be an erroneous one, from the experiments of the Government chemist of Ootacamund (Mr Broughton), who, after a most careful chemical a.n.a.lysis, failed to discover either quinine, quinidine, cinchonine, cinchonidine, or the least trace of any one of the cinchona alkaloids.

When the leaves of the _Eucalyptus globulus_ are held to the light they reveal the presence of little semi-transparent dots, which are found to be receptacles for a volatile oil, that may be obtained in large quant.i.ty by submitting the plant to aqueous distillation.

This volatile oil has been examined by Cloez, who found it to consist chiefly of a substance allied in chemical characters to camphor, which substance he named _eucalyptol_.[287] Any therapeutic power possessed by the eucalyptus may be referred to this substance, since, as just stated, it cannot be due to a bark alkaloid.

[Footnote 287: Messrs Faust and Homeyer state that Cloez's "Eucalyptol" is a mixture of terpen and cymol.]

Before finis.h.i.+ng our notice of the reputed curative effects of the eucalyptus we may mention that Dr Gimbert employs the leaves instead of lint for dressing wounds and fetid ulcers, and says he has found them, when thus used, excellent deodorisers; that another method of employing the leaves of the eucalyptus consists in having them made into cigarettes, which are reported to be useful in asthma and bronchial complaints.

Lastly, let us state that another species of eucalyptus exudes a very astringent substance, which, from its appearance and properties, being so a.n.a.logous to kino, has been denominated _Botany Bay kino_. (See EUCALYPTIN.)

The essential oil of eucalyptus, which, according to the species of the plant from which it is obtained, varies in colour from light yellow to light blue, is now largely employed as a diluent for the more delicate volatile oils used in perfumery.

Many species of the eucalyptus yield excellent timber, possessed of great hardness and durability, and little affected by moisture. This timber has the power of resisting the attacks of insects. The wood of the eucalyptus is also very rich in potash. The maple and the elm, which are regarded as yielding a large per-centage of this substance, afford only about half as much as can be obtained from the eucalyptus, this latter tree yielding 21 per cent. of potash.

The barks of different species have also been advantageously utilised for paper making, as well as for tanning.

In this country eucalyptus seeds are reared in a greenhouse. They may be sown in a mixture of loam, peat, and ordinary soil, with a sprinkling of sand on the surface.

The following directions for the cultivation of the eucalyptus in England were communicated to the 'Medical Times and Gazette' of 1873 by Mr Bennett Stanford, of Pyt House, Tisbury:--"I have successfully reared from seed two dozen of these trees, and they are now growing well out of doors. I obtained the seed five years ago from South Australia, and forced it in a hothouse; in one year it was four feet high, and now, in its fifth year, it is growing rapidly in a sheltered position in the park, having attained a height of thirty feet. The first three years the tree must be taken under cover in the winter, and the fourth and fifth years should be protected for several feet up with wisps of hay or straw. When the trees are kept indoors in winter it should be in an orangery or very high greenhouse, with plenty of light and a little water."

=EUCHLO"RINE.= A bright-yellow gas, prepared by gently heating chlorate of pota.s.sa with hydrochloric acid. It is probably a mixture of chlorous acid and free chlorine. Prof. Stone, of Manchester, has found Euchlorine of a great service as an aerial disinfectant.

=EUGLENae.= These are ciliated infusorial animalcules inhabiting ponds and water-tanks. Sometimes they abound in water in quant.i.ties so enormous as to impart to that fluid a blood-red appearance. The princ.i.p.al species are the _Euglena viridis_ and the _Euglena pyrum_. Their presence is supposed to indicate the existence in the water in which they are found, of decaying animal and vegetable matter upon which they are believed to feed.

=EUPHOR'BIUM.= _Syn._ GUM EUPHORBIUM; EUPHORBIUM (Ph. E.), L. The concrete resinous juice of the _Euphorbia canariensis_, and other species of the same genus. It is a powerful acrid, purgative, rubefacient, sternutatory, and vesicant, and the violence of its action has led to its disuse.

=EU'PIONE.= An ethereal liquid forming the chief portion of the light oil of wood-tar, and which also exists in the tar obtained during the destructive distillation of animal substances, and in the fluid product of the distillation of rape oil. It is separated from these substances by agitating them with oil of vitriol, or a mixture of oil of vitriol and nitre, and subsequent cautious distillation. Pure eupione is tasteless, exceedingly thin, limpid, and aromatic; boils at 116 Fahr.; and is the lightest fluid known; sp. gr. 655. It is very inflammable, burns with a very bright flame, and gives a transient greasy stain to paper. It is isomeric with hydride of amyl. Other volatile hydrocarbons of like origin are often confounded with eupione by chemical writers.

=EUPYR'ION.= Any contrivance for obtaining instantaneous light; as a lucifer match, &c.

=EVAC'UANTS.= _Syn._ EVACUANTIA, L. Medicines which augment the secretions or excretions. CATHARTICS, DIAPh.o.r.eTICS, DIURETICS, EMETICS, ERRHINES, EXPECTORANTS, and SIALOGOGUES, belong to this cla.s.s.

=EVAPORA'TION.= The conversion of a fluid into vapour by means of heat, diminished atmospheric pressure, or exposure to a dry atmosphere.

Evaporation is had recourse to--1. For the vapour as a source of heat or power, as in the case of steam-boilers, &c.;--2. To separate volatile fluids from impurities or other bodies, which are either fixed or less volatile;--3. To recover solid bodies from their solutions, as in the preparation of extracts, chemical salts, &c.;--4. To concentrate or strengthen a solution by the expulsion of some of the fluid matter that forms the menstruum;--5. To purify liquids by the dissipation of the volatile matters which may contaminate them.

It is found that, under ordinary circ.u.mstances, evaporation is confined to the surface of the heated liquid, and is therefore slower or quicker, in proportion to the extension of that surface. Hence has arisen the adoption of wide, shallow vessels for containing fluids during their exposure to heat for this purpose. Evaporation proceeds most rapidly when a current of air (especially hot and dry air) is made to pa.s.s over the surface of the fluid; as, in this ease, the vapour is prevented from resting upon the surface, and impeding the process by its pressure. For a similar reason, liquids evaporate more rapidly in vessels partially covered than in open ones. In the former case the cool inc.u.mbent air condenses and throws back a portion of the vapour, which thereupon, besides its cooling action, offers mechanical resistance to the diffusion of the vaporous particles as they arrive at the surface of the liquid. In the latter case these obstacles are avoided, and the impetus of the vapour pouring forth from a contracted orifice (or pipe), not only readily overcomes the pressure of the atmosphere, but offers less surface for its cooling action, until it has pa.s.sed much beyond the points at which it can exert any influence on the fluid from which it has escaped. In this way the chemical action of the atmosphere on the liquid operated on is also considerably lessened. On the small scale, shallow capsules of gla.s.s, wedgwood-ware, porcelain, or metal, are commonly employed as evaporating vessels, and these are exposed to heat by placing them over a lamp, or naked fire, or in a water bath, or sand bath, according to the temperature at which it is proper to conduct the process. On the large scale, high-pressure steam is usually employed as the source of heat. The term 'spontaneous evaporation' is applied to the dissipation of a fluid by mere exposure in open vessels, at the common temperature of the atmosphere, and without the application of artificial heat. The celerity of this species of evaporation wholly depends on the degree of humidity of the surrounding air, and differs from the former, in which the rate of evaporation is proportionate to the degree of heat at which the process is conducted, and the amount of pressure upon the surface of the liquid. Evaporation '_in vacuo_' (as it is called) is conducted under the receiver of an air-pump, or in an attenuated atmosphere, produced by filling a vessel with steam, by which means the air is expelled, when all communication with the external atmosphere is cut off, and the vapour condensed by the application of cold. Fluids are also evaporated in air-tight receivers over sulphuric acid, by which they are continually exposed to the action of a very dry atmosphere. When such a receiver is connected with an air-pump in action, evaporation proceeds with increased rapidity, and intense cold is produced. It appears, from the experiments of Dr Ure, that "if the bottom of a pan, and the portion of the sides immersed in a hot fluid medium (solution of chloride of calcium, for example), be corrugated, so as to contain a double expanse of metallic surface, that pan will evaporate exactly double the quant.i.ty of water, in a given time, which a like pan, with smooth bottom and sides, will do, immersed equally deep in the same bath. If the corrugation contain three times the quant.i.ty of metallic surface, the evaporation will be threefold in the above circ.u.mstances. But if the pan, with the same corrugated bottom and sides, be set over a fire, or in an oblong flue, so that the current of flame may sweep along the corrugations, it will evaporate no more water from its interior than a smooth pan of like shape and dimensions placed alongside it in the same flue, or over the same fire."

In the laboratory, steam heat is now almost exclusively employed. Copper, or tinned, glazed, or silvered coppered pans, boilers, and stills, are surrounded by a 'jacket' of cast iron, and high-pressure steam admitted between the two. By due management of the supply-c.o.c.k, a range of temperature may be thus obtained extending from about 90 to 325 Fahr.

It is found that, under ordinary circ.u.mstances, 10 square feet of heated surface will evaporate fully 1 lb. of water per minute; and that a thin copper tube exposing 10 feet surface will condense about 3 lbs. of steam per minute, with a difference of temperature of about 90 Fahr. This is equal to 30 Fahr. per lb.; and, consequently, the heat of the steam employed to produce the evaporation should be 212 + 30 = 242 Fahr.

An attention to the facts and principles thus briefly explained above will be found of great value in the laboratory.

=EXCIP'IENT.= See PRESCRIPTION.

=EXCI'TANTS.= See STIMULANTS.

=EXCORIA'TIONS.= _Syn._ _Sprays_, CHAFINGS.

In _surgery_ and _pathology_, superficial injuries or affections of the skin, consisting of the removal of the scarf-skin or cuticle, accompanied with more or less irritation and slight inflammations. When arising from rough friction or attrition, they are more commonly called abrasions.

Young children are very apt to be chafed under the arms, behind the ears, between the thighs, and in the wrinkles and folds of the skin generally, unless great attention is paid to cleanliness, and wiping the skin perfectly dry after was.h.i.+ng them. Whenever there is a tendency to excoriations of this kind, either in adults or children, a little finely powdered starch, or violet powder, applied by means of a puff, or a small bag of muslin, once or twice a day, will generally remove them, and prevent their occurrence in future. Mild unguents, as cold cream, or spermaceti cerate or ointment, may also be used with advantage. The preference should, however, be given to the remedies first named, from their not soiling the linen. See ABRASION.

=EXCRETA.= The excrement.i.tious matter evacuated from the bowels varies of course in composition and quant.i.ty according to the food from which it is derived.

Berzelius found a sample a.n.a.lysed by himself to yield about seventy-five per cent. of water, the remainder being made up of alimentary waste, and biliary matter. A large amount of phosphates of calcium and magnesium was found in the ash remaining after the incineration of the solid matter. A specimen of faecal matter examined by Playfair yielded 15 per cent. of nitrogen and 45 per cent. of carbon. Marcet states that he has obtained from excrement a crystallisable body possessing an alkaline reaction; to which he gives the name _excretin_; also a fatty substance, which he terms _excretolic acid_. To excretin he a.s.signs the formula C_{7}_{8}H_{1}_{5}_{6}SO_{2}; the composition of the acid has not been determined.

Hinterberger has succeeded in getting excretine (excretin), free from sulphur, and gives as its simplest formula C_{2}_{0}H_{3}_{6}O; which shows a close resemblance to cholesterin, C_{2}_{6}H_{4}_{4}O.

But cholesterin is less easily dissolved in vinegar than excretin, and the solution deposits crystals which, when viewed by the microscope, are found to be beautiful silky six-sided prisms, while the excretin solution yields round ma.s.ses.

Treated with bromine, excretin gave a crystalline body having the formula C_{2}_{0}H_{3}_{4}Br_{2}O; but the author did not succeed in preparing a chlorinated compound of excretin.

In the excreta of carnivorous animals no excretin has been discovered, although a substance resembling it has been found. Cholesterin has been obtained from the faeces of the crocodile, but no urates; whilst the excreta of the boa contain urates, but are dest.i.tute of cholesterin.

The faeces of animals that live on vegetables contain neither excretin, butyric acid, nor cholesterin.

The excreta of birds and serpents, which mixed with the secretion from the kidneys, are discharged from the animals by the cavities, are very similar to urine, and consist chiefly of alkaline urates and earthy phosphates.

The excrements of insects consist mainly of the remnants of the tissues, animal or vegetable which they have swallowed as food, mixed with const.i.tuents of the urine, provided the insect has no special urinary organs.

Brieger examined the faeces of healthy persons, and of convalescents, and found in addition to acetic, butyric, and isobutyric acids, small quant.i.ties of phenol and indol, and a new crystallisable body, which he terms _skatol_ (_skatos_, faeces). It crystallises in irregular-dentate s.h.i.+ning plates, resembling indol, which by frequent recrystallisation from hot water, can be obtained snow white. Skatol forms the chief const.i.tuent of the volatile aromatic components of human faeces. Faeces of dogs (whether fed on meat or bread diet) contained no skatol, but indol, and in addition a yellow oil, with a revolting and peculiarly irritating smell.

Brieger has not yet been able to a.n.a.lyse this yellow oil, although it forms the chief volatile const.i.tuent of dogs' faeces. He has repeatedly obtained it from distillation from human pathological fluids. In the pancreas after putrefaction, and in the faeces of typhus patients, no skatol was found. The author considers skatol identical with the substance which Secretan obtained by the decomposition of egg alb.u.men under water for six months.

Skatol injected under the skin of rabbits, pa.s.ses out in the urine as a substance yielding colouring matter. Skatol is believed by the author to be the substance in human urine which, according to Jaffe, yields a red or violet colour on the addition of hydrochloric acid and chloride of lime.

Phenol, the author finds, is a constant component of human faeces. The above results show that specific products of decomposition are normal components of intestinal digestion.[288]

[Footnote 288: 'Deut. Chem. Ges. Berg.,' x, 1027-1031.]

Liebig calculated that the daily average amount of faecal matter pa.s.sed by a man is 5-1/2 oz; Lawes says that it averages in healthy male adults, 42 oz; Parkes estimates it (in Europe) at 4 oz. on the average; Letheby at 2784, and Frankland at 3 oz. In India, a native on the average excretes as much as 12 oz., this increase over the above quant.i.ties being due to the large proportion of rice and farinaceous food of which the Hindoos'

diet consists.

The daily average amount of urine excreted by a human being has been given by Lawes at 46 oz.; Parkes places it at 50 oz. by measure for each male adult; Letheby at 31851, and Frankland at nearly 40 oz. by measure.

According to Parkes' figures a population of a thousand persons, would thus void daily 156 lbs. of solids, and 260 gallons of urine; or 25 tons of faeces, and 91,250 gallons of urine per annum; whilst according to Letheby, from the same number of people, the daily discharge would be 2266 lbs. avoirdupois of urine and 1775 lbs. of faeces.

Messrs Lawes and Gilbert estimate the manurial value of the urine and faeces together at 6s. 8d. per annum for every individual, which corresponds to a yearly produce of about 10 lbs. of ammonia; but Messrs Hoffman, Witt, and Thudichum a.s.sess it at 8s. 6d. for a mixed population of both s.e.xes and of all ages, which they say represents about 13 lbs. of ammonia.

Faecal matter decomposes much more rapidly when mixed with urine than it would otherwise do, ammonia and fetid gases being given off in considerable quant.i.ties. Should much water be also present, and the temperature moderately high, light carburetted hydrogen, carbonic anhydride, nitrogen, and sulphuretted hydrogen are likewise evolved.