Cooley's Cyclopaedia of Practical Receipts Volume I Part 191

GAMBOGE, 70% of _pure gamboge resin_, and 2% of _gum_.

GUAIAc.u.m, 80% of _pure guaiac.u.m resin_.

GUM AMMONIAc.u.m, 70% of _resin_, and 18% of _gum_.

JALAP,[265] 11% of _pure jalap resin_.

MYRRH, 30% of _pure resin_, and 50% of _gum_.

OPIUM, 9% of _pure morphia_.

RHUBARB,[266] 40% of _soluble matter_.

SAGAPENUM, 50% of _resin_, 30% of _gum_, and 30% of _volatile oil_.

SCAMMONY, 70% of _pure scammony resin_.

SENNA, 28% of _soluble matter_.

Medicinal leaves, flowers, barks, roots, extracts, &c., not specified above, must be, when imported, in perfect condition, and of as recent collection and preparation as practicable.

Pharmaceutical and chemical preparations, whether crystallised or otherwise, used in medicine, to be pure and of a proper consistence and strength, as well as of perfect manufacture, conformably with the standard authorities named in the Act; and must, in no instance, contain over 3% of excess of moisture or water of crystallisation.

Essential or volatile oils, and expressed oils used in medicine must be pure and of the standard sp. gr. noticed and declared in the dispensatories named in the above Act.

"Patent" or "Secret Medicines" are by law subject to the same examination as other medicinal preparations, and cannot be permitted to pa.s.s the Custom-house for home consumption, but must be rejected and condemned, unless the special examiner is satisfied, after due investigation, that they are fit and safe to be used for medical purposes.

An appeal from the examiner to the collector to be admitted within 10 days.

JAMES GUTHRIE, _Secretary to the Treasury_.

[Footnote 264: Of whatever denomination.]

[Footnote 265: Root in powder.]

[Footnote 266: Only Turkey, East Indian, and Russian, admissible.]

=DRUM'MOND LIGHT.= See LIGHT (Artificial).

=DRUNK'ENNESS.= See ABSTINENCE, INTEMPERANCE, &c.

=DRY'ERS (Painter's).= _Prep._ 1. Litharge (best) ground to a paste with drying-oil. For dark colours.

2. From white copperas and drying oil; as the last.

3. From sugar of lead and drying oil. The last two are for pale colours.

4. From white copperas and sugar of lead, of each 1 lb.; pure white lead, 2 lbs. For 'whites,' and opaque light colours, greys, &c.

Dryers are employed, as the name implies, to increase the drying and hardening properties of oil paints. A little is beat up with them at the time of mixing them with the oil and turpentine for use.

=DRY'ING.= See DESICCATION, &c.

=DRY'ING-OIL.= See OILS.

=DRY-ROT.= A peculiar disease that attacks wood, and renders it brittle and rotten. It is generally caused by dampness and the subsequent development of the spores of fungi, particularly those of _Merulius lacrymans_ and _vastator_ and _Polyporus destructor_. The dry-rot princ.i.p.ally attacks 'ill-seasoned' timber, and more particularly that of ships and badly ventilated buildings.

_Prev._ Various means have been proposed to prevent the attacks of dry-rot and to arrest its progress when it has commenced, among which the process called 'KYANIZING' (Kyan's patent) is that most generally known and most extensively adopted. It consists in immersing the timber in a bath of corrosive sublimate. The process termed 'PAYNIZING' (Payne's patent) consists in first filling the pores with a solution of chloride of calcium, under pressure, and next forcing in a solution of sulphate of iron, by which an insoluble sulphate of lime is formed in the body of the wood, which is thus rendered nearly as hard as stone. Wood so prepared is now largely employed in our public works and railways. Sir W. Burnett's process (patented in 1836) consists in impregnating the timber with a solution of chloride of zinc. Mr J. Beth.e.l.l's process (patented in 1838) consists in thoroughly impregnating the wood with oil of tar containing creasote and a crude solution of acetate of iron, commonly called 'pyrolignite of iron.' The impregnation is effected in a strong cylindrical vessel, connected with a powerful air-pump, so that in the first instance a vacuum being formed, and subsequently a pressure of several atmospheres applied, the liquid may as much as possible be forced into all the pores of the wood. The above processes for 'seasoning'

preserve the timber not only from dry-rot, but from the influence of the weather and the attacks of insects and worms.

"The construction of air-drains or pa.s.sages around wood-work to be preserved is, where the method is applicable, a great aid to the preservation of wood. Dry-rot is both prevented in new buildings and cured in old ones by filling up the s.p.a.ces between the floor-joists with 'tank-waste' from alkali works. This can also be applied to the ends of beams resting in walls."--_Chemical News._

=DUB'BING.= _Prep._ 1. By boiling the waste cuttings of sheep-skins in crude cod oil. 2. Black resin, 2 lb.; tallow, 1 lb.; crude cod oil or train oil, 1 gall.; boil to a proper consistence. Used by the curriers to dress leather, and by shoemakers and others to soften leather, and to render boots and shoes waterproof.

=DUBOISIA MYOPOROIDES.= (Nat. order, _Solanacae_.) A small tree growing in Australia, New Caledonia, and New Guinea. The leaves have been used in Brisbane and Sydney as a subst.i.tute for atropine, and extract of belladonna; to both of which Mr Tweedy believes them to be superior in prompt and energetic action. Mr Tweedy further states that, in every case in which he has used _duboisia_ to produce dilatation of the pupil of the eye, its action has been beneficial, and he is induced to conclude, more advantageous than that of atropine. According to Dr Ringer, _duboisia_, besides causing dilatation of the pupil, quickens the pulse, parches the tongue, stops the secretions of the skin, and induces headache and drowsiness. He also reports that it is antagonistic in its action to muscarine, and produces teta.n.u.s after the lapse of some hours or days.

For an account of the botanical properties of the plant, the reader is referred to a paper by Mr E. M. Holmes in the 'Pharmaceutical Journal' for March 9th, 1878; and to the 'Lancet' of March 2nd, 1878, for some experiments on its physiological effects by Messrs Ringer and Tweedie. The _Duboisia myoporoides_ was introduced into medical practice by Dr Bancroft, of Brisbane.

Since the above has been written, Mr Gerrard has obtained a powerful alkaloid from an extract of the leaves of the Duboisias, very similar in chemical properties to aconite, and possessed of the same physiological qualities as the extract.

=DUCK.= See POULTRY.

=DUCTIL'ITY= is the property of being drawn out in length without breaking. See METALS.

=DULCAMA'RA.= See NIGHTSHADE (Woody).

=DUMB'NESS.= _Syn._ APHONIA, L. As speech is an acquired and imitative faculty, persons who are either born deaf or become so in early infancy are also, necessarily, dumb. The first step in treating dumbness must therefore be directed to the removal of the deafness on which the imperfection rests. The exertions of modern philanthropists have, however, been so far successful in such cases as to enable the deaf-mute to converse with those around him by signs. Those interested in the subject may consult an admirable treatise on 'Deaf-dumbness,' by M. E.

Hubert-Valleroux, of which an excellent translation appeared in the 'Medical Circular,' vol. ii, for 1853. See DEAFNESS.

=DUMPLINGS, Norfolk.= Mix half a pound of flour with half a teaspoonful of baking powder and a pinch of salt; make into a little dough with cold water; fall into small b.a.l.l.s, put them into boiling water immediately, and boil for twenty minutes.

=DUNGER--MANURE= (Boutin, Paris). A bluish-green fluid, containing about 190 grammes of solid matter per litre. The residue consists of sulphates of copper, iron, magnesia, and soda, sal ammoniac, nitrates of potash and soda, common salt, and none or a mere trace of phosphoric acid. The blue deposit which separates on standing is ultramarine. (Keller, Karmrodt, and Nessler.)

=DUNG'ING.= _Syn._ CLEANSING. One of the princ.i.p.al processes in the arts of calico printing and dyeing, its object being to free the cloth from loose matters, which would interfere with the dyeing. After the thickened mordants have been applied to the fabric and properly fixed, it is necessary to remove the now useless thickening matter, together with the excess of mordant, which has not come into actual contact with the cloth.

Formerly a bath formed of cow-dung, diffused through hot water (130 to 212 Fahr.) was always used to wash away these loose matters; but now various manufactured substances are successfully employed for the purpose.

The best dung subst.i.tutes are the a.r.s.enite and a.r.s.eniate of soda, the silicate of soda, and phosphate of lime. Experience proves that, in the case of these subst.i.tutes, a final rinse in cow-dung before dyeing is advantageous. A process very similar to 'dunging' is employed after dyeing, to clear and give purity to the undyed parts. This subsequent process is distinguished by the term 'clearing.' Cow-dung has been used in 'clearing' operations, but its employment is not to be recommended. Bran scalded and mixed with water is employed for certain goods, but bleaching powder is the most generally used 'clearing agent.'

=DUST, ATMOSPHERIC.= When a ray of sunlight is admitted into a dark room, or an electric beam is transmitted through a gla.s.s tube, myriads of little motes are revealed, which move and dance about in all directions.

In ordinary daylight these minute particles are invisible. Nevertheless, they are always more or less present in the atmosphere wherever (except under special conditions) this permeates, and they const.i.tute that more or less attenuated, impalpable, generally dry, or dessicated form of matter which we denominate dust.

As with every inspiration we take into our bodies more or less of this suspended material, the study of the composition and characters of the different substances which compose it is one possessed of paramount interest, both for the pathologist and sanitarian.

Amongst solid, inorganic matters found in the open air are silica, peroxide of iron, silicate of alumina, carbonate and phosphate of lime, sand, carbon, chloride of sodium, and metallic iron. These, of course, are of telluric origin, and are carried into the atmosphere by strong currents and winds, which latter have the power of transporting dust to great distances, _e.g._ red sand from the interior of Africa has been found in the sails of ships 600 or 800 miles distant from the African coast, whilst particles of carbon, sand, and dried mud, ejected to great heights from volcanoes into the air, have been transported over still greater distances.

Some doubt appears to prevail as to whether all dust storms originate on the earth, it having been conjectured that some of the solid matters found in the atmosphere may be of meteoric origin, and may have entered it from the realms of s.p.a.ce. The chloride of sodium (which the chemist knows is so omnipresent that he cannot heat an ordinary platinum wire in a Bunsen burner without indications of its presence) is derived from the spray of the sea, lifted and diffused into the air by the wind; the iron dust from the rails over which railway trains are constantly pa.s.sing; the silica, amongst other sources, from the traffic over macadamised thoroughfares.

The organised and organic substances contained in the external air are very numerous. The animal kingdom is the source of the wings of moths, b.u.t.terflies, and other insects, spiders' legs and webs, hair, wool, epithelium, and eggs, many of these bodies being mere _debris_.