Cooley's Cyclopaedia of Practical Receipts Volume Ii Part 284

=Vapour of Benzoin.= _Syn._ VAPOR BENZOINI. (St Th. Hosp.) Compound tincture of benzoin, 1 oz. A teaspoonful to 1 pint of water at 140 F. In acute inflammation of the pharynx and larynx.

=Vapour of Carbolic Acid.= _Syn._ VAPOR ACIDI CARBOLICI. (St Th. Hosp.) Carbolic acid, 420 gr.; water, 1 dr.; 20 drops of this in 1 pint of water, at 140 F., for each inhalation. For syphilitic and carcinomatous ulcerations.

=Vapour of Chlorine.= _Syn._ VAPOR CHLORI. (B. P.) Put chlorinated lime, 2 oz., into a suitable apparatus, moisten it with cold water, and let the vapour that arises be inhaled.

=Vapour of Conia.= _Syn._ VAPOR CONIae. (B. P.) Mix extract of hemlock, 60 gr.; solution of potash, 1 dr.; and distilled water, 9 dr. Put 20 minims of the mixture on a sponge, in a suitable apparatus, that the vapour of hot water pa.s.sed over it may be inhaled.

=Vapour of Creosote.= _Syn._ VAPOR CREOSOTI. (B. P.) Mix creosote, 12 minims, and boiling water, 8 oz., in an apparatus so arranged that air may be inhaled through the solution.

=Vapour of Hop.= _Syn._ VAPOR LUPULI. (St Th. Hosp.) Oil of hops, 6 minims; light carbonate of magnesia, 10 gr.; water, 1 oz. A teaspoonful in 1 pint of water, at 140 F., for each inhalation. Sedative.

=Vapour of Hydrocyanic Acid.= _Syn._ VAPOR ACIDI HYDROCYANICI. (B. P.) Mix from 10 to 15 minims of diluted hydrocyanic acid with 1 dr. of cold water in a suitable apparatus, and let the vapour that arises be inhaled.

=Vapour of Iodine.= _Syn._ VAPOR IODI. Mix tincture of iodine, 1 fl. dr., and water, 1 oz., and, having applied a gentle heat, let the vapour that arises be inhaled.

=Vapour of Lactic Acid.= _Syn._ VAPOR ACIDI LACTICI. (St Th. Hosp.) Lactic acid, 20 minims; distilled water, 1 oz.; mix. For spray inhalation.

Dissolves the membranous exudation in diphtheria,

=Vapour of Oil of Juniper.= _Syn._ VAPOR OLEI JUNIPERI. (St Th. Hosp.) English oil of juniper, 20 minims; light carbonate of magnesia, 10 gr.; water, 1 oz. A teaspoonful to 1 pint of water at 140 F. for each inhalation. For vocal weakness.

=Vapour of Oil of Mountain Pine.= _Syn._ VAPOR PINI PLUMILIONIS. (St Th.

Hosp.) Oil of mountain pine, 1/2 dr.; light carbonate of magnesia, 15 gr.; water, 1 oz.; 1 dr. to 1 pint of water at 140 F. for each inhalation. In chronic laryngitis.

=Vapour of Oil of Myrtle.= _Syn._ VAPOR OLEI MYRTI. (St Th. Hosp.) Oil of myrtle, 6 minims; light carbonate of magnesia, 6 gr.; water, 1 oz. A teaspoonful in a pint of water at 140 F. for each inhalation. In acute tonsillitis.

=Vapour of Nitrite of Amyl.= _Syn._ VAPOR AMYL NITRITIS. (St Th. Hosp.) Nitrite of amyl, 8 minims; rectified spirit, 1 oz. A teaspoonful in a pint of water at 100 F. for each inhalation. In asthma and spasm of the glottis.

=Vapour of Scotch Pine.= _Syn._ VAPOR PINI SYLVESTRIS. Oil of Scotch pine (fir-wood oil), 40 minims; light carbonate of magnesia, 20 gr.; water, 1 oz.; 1 dr. to 1 pint of water at 140 F. for each inhalation. In chronic laryngitis.

=Vapour of Sulphurous Acid.= _Syn._ VAPOR ACIDI SULPHUROSI. (St Th. Hosp.) Sulphurous acid, 15 minims; water, 1 oz. For spray inhalation. Stimulant and antiseptic.

=Vapour of Thymol.= _Syn._ VAPOR THYMOLIS. Thymol, 6 gr.; rectified spirit, 1 dr.; light carbonate of magnesia, 3 gr.; water, 1 oz. 1 dr. to 1 pint of water at 140 F. for each inhalation. In pharyngitis and laryngitis when a.s.sociated with exanthemata.

=VARICOSE VEINS.= See VARIX.

=VARIX.= The permanent unequal dilation of a vein or veins, which are then said to be 'varicose.' It is known by the presence of a soft tumour, which does not pulsate, and often a.s.sumes a serpentine figure. Varicose veins of the groin and s.c.r.o.t.u.m generally form a collection of knots. The treatment consists of cold applications, and pressure from bandages. Some cases are relieved by ligature. When occurring in the legs, much standing or walking should be avoided, and the use of the elastic stockings made for the purpose will be proper.

=VAR'NISH.= _Syn._ VERNIS, Fr. Any liquid matter, which, when applied to the surface of a solid body, becomes dry, and forms a hard glossy coating, impervious to air and moisture.

Varnishes are commonly divided into two cla.s.ses--FAT or OIL VARNISHES and SPIRIT VARNISHES. The fixed or volatile oils, or mixtures of them, are used as vehicles or solvents in the former, and concentrated alcohol in the latter.[254] The sp. gr. of alcohol for the purpose of making varnishes should not be more than 8156 (= 67 o. p.), and it should be preferably chosen of even greater strength. A little camphor is often dissolved in it, to increase its solvent power. The oil of turpentine, which is the essential oil chiefly employed for varnishes, should be pure and colourless. Pale drying linseed oil is the fixed oil generally used; but poppy oil and nut oil are also occasionally employed. Among the substances which are dissolved in the above menstrua are--amber, anime, copal, elemi, lac, mastic, and sandarach, to impart body and l.u.s.tre; benzoin, on account of its agreeable odour; annotta, gamboge, saffron, socotrine aloes, and turmeric, to give a yellow colour; dragon's blood and red sandal wood, to give a red tinge; asphaltum, to give a black colour and body; and caoutchouc to impart toughness and elasticity.

[Footnote 254: Methylated spirit is now generally used for making spirit varnishes, in place of duty-paid alcohol.]

In the preparation of spirit varnishes care should be taken to prevent the evaporation of the alcohol as much as possible, and also to preserve the portion that evaporates. On the large scale, a common still may be advantageously employed; the head being furnished with a stuffing-box, to permit of the pa.s.sage of a vertical rod, connected with a stirrer at one end and a working handle at the other. The gum and spirit being introduced, the head of the still closely fitted on and luted, and the connection made with a proper refrigerator, heat (preferably that of steam or a water bath) should be applied, and the spirit brought to a gentle boil, after which it should be partially withdrawn, and agitation continued until the gum is dissolved. The spirit which has distilled over should be then added to the varnish, and after thorough admixture the whole should be run off, as rapidly as possible, through a silk-gauze sieve, into stone jars, which should be immediately corked down, and set aside to clarify. On the small scale, spirit varnishes are best made by maceration in closed bottles or tin cans, either in the cold or by the heat of a water bath. In order to prevent the agglutination of the resin, it is often advantageously mixed with clean siliceous sand or pounded gla.s.s, by which the surface is much increased, and the solvent power of the menstruum greatly promoted.

To ensure the excellence of oil varnishes, one of the most important points is the use of good drying oil. Linseed oil for this purpose should be very pale, perfectly limpid or transparent, scarcely odorous, and mellow and sweet to the taste.--100 galls. of such an oil is put into an iron or copper boiler, capable of holding fully 150 galls., gradually heated to a gentle simmer, and kept near that point for about 2 hours, to expel moisture; the sc.u.m is then carefully removed, and 14 lbs. of finely pulverised scale litharge, 12 lbs. of red lead, and 8 lbs. of powdered umber (all carefully dried and free from moisture), are gradually sprinkled in; the whole is then kept well stirred, to prevent the driers sinking to the bottom, and the boiling is continued at a gentle heat for about 3 hours longer; the fire is next withdrawn, and, after 30 to 40 hours' repose, the sc.u.m is carefully removed, and the clear supernatant oil decanted from the 'bottoms,'--The product forms the best boiled or drying oil of the varnish maker.--Another method is to heat a hogshead of the oil gradually for 2 hours, then to gently simmer it for about 3 hours longer, and, after removing the sc.u.m, to add, gradually, 1 lb. of the best calcined magnesia, observing to mix it up well with the oil, and, afterwards to continue the boiling pretty briskly for at least an hour, with constant agitation. The fire is then allowed to die away, and, after 24 hours, the oil is decanted as before. The product is called 'clarified oil,' and requires to be used with driers. It should be allowed to lay in the cistern for 2 or 3 months to clarify.

In the preparation of oil varnishes, the gum is melted as rapidly as possible, without discolouring or burning it; and when completely fused, the oil, also heated to nearly the boiling point, is poured in, after which the mixture is boiled until it appears perfectly h.o.m.ogeneous and clear, like oil, when the heat is raised, the driers (if any are to be used) gradually and cautiously sprinkled in, and the boiling continued, with constant stirring, for 3 or 4 hours, or until a little, when cooled on a palette knife, feels strong and stringy between the fingers. The mixture is next allowed to cool considerably, but while still quite fluid, the turpentine, previously made moderately hot, is cautiously added, and the whole thoroughly incorporated. The varnish is then run through a filter or sieve into stone jars, cans, or other vessels, and set aside to clarify itself by subsidence. When no driers are used, the mixture of oil and gum is boiled until it runs perfectly clear, when it is removed from the fire, and, after it has cooled a little, the turpentine is added as before.

It is generally conceived that the more perfectly the gum is fused, or run, as it is called, the larger and stronger will be the product; and the longer the boiling of the 'gum' and oil is continued, within moderation, the freer the resulting varnish will work and cover. An excess of heat renders the varnish stringy, and injures its flowing qualities. For pale varnishes as little heat as possible should be employed throughout the whole process. Good body varnishes should contain 1-1/2 lb.; carriage, wainscot, and mahogany varnish, fully 1 lb.; and gold size and black j.a.pan, fully 1/2 lb. of gum per gall., besides the asphaltum in the latter. Spirit varnishes should contain about 2-1/2 lbs. of gum per gall.

The use of too much driers is found to injure the brilliancy and transparency of the varnish. Copperas does not combine with varnish, but only hardens it; sugar of lead, however, dissolves in it to a greater or less extent. Boiling oil of turpentine combines very readily with melted copal, and it is an improvement on the common process, to use it either before or in conjunction with the oil, in the preparation of copal varnish that it is desired should be very white. Gums of difficult solubility are rendered more soluble by being exposed, in the state of powder, for some time to the air.

Varnishes, like wines, improve by age; and should always be kept as long as possible before use.

From the inflammable nature of the materials of which varnishes are composed, their manufacture should be only carried on in some detached building of little value, and built of uninflammable materials. When a pot of varnish, gum, or turpentine catches fire, it is most readily extinguished by closely covering it with a piece of stout woollen carpeting, which should be always kept at hand, ready for the purpose.

An excellent paper, by Mr J. W. Niel, on the manufacture of varnishes, will be found in the 'Trans. of the Soc. of Arts,' vol. xlix. See also the articles ALCOHOL, AMBER, COPAL, OILS, &c., in this work.

=Varnish, Am'ber.= _Prep._ 1. Take of amber (clear and pale), 6 lbs.; fuse it, add of hot clarified linseed oil, 2 galls.; boil until it 'strings well,' then let it cool a little, and add of oil of turpentine 4 galls, or q. s. Nearly as pale as copal varnish; it soon becomes very hard, and is the most durable of the oil varnishes; but it requires some time before it is fit for polishing, unless the articles are 'stoved.' When required to dry and harden quicker, drying oil may be subst.i.tuted for the linseed oil, or 'driers' may be added during the boiling.

2. Amber, 4 oz.; pale boiled oil, 1 quart; proceed as last. Very hard.

3. Pale transparent amber, 5 oz.; clarified linseed oil or pale boiled oil, and oil of turpentine, of each 1 pint; as before.

_Obs._ Amber varnish is suited for all purposes where a very hard and durable oil varnish is required. The paler kind is superior to copal varnish, and is often mixed with the latter to increase its hardness and durability. The only objection to it is the difficulty of preparing it of a very pale colour. It may, however, be easily bleached with some fresh-slaked lime.

=Varnish, Balloon.= See VARNISH, FLEXIBLE (_below_).

=Varnish, Bessemer's.= This consists of a pale oil copal varnish, diluted with about 6 times its volume of oil of turpentine, the mixture being subsequently agitated with about 1-30th part of dry slaked lime, and decanted after a few days' repose. Five parts of the product mixed with 4 parts of bronze powder forms 'Bessemer's gold paint.'

=Varnish, Black.= _Prep._ 1. (BLACK AMBER VARNISH.) From amber, 1 lb.; fuse, add, of hot drying oil, 1/2 pint; powdered black resin, 3 oz.; asphaltum (Naples), 4 oz.; when properly incorporated and considerably cooled, add of oil of turpentine, 1 pint. This is the beautiful black varnish of the coachmakers.

2. (IRONWORK BLACK.) From asphaltum, 48 lbs.; fuse, add of boiled oil, 10 galls.; red lead and litharge, of each 7 lbs.; dried and powdered white copperas, 3 lbs.; boil for 2 hours, then add of dark gum amber (fused), 8 lbs.; hot linseed oil, 2 galls.; boil for 2 hours longer, or until a little of the ma.s.s, when cooled, may be rolled into pills, then withdraw the heat, and afterwards thin it down with oil of turpentine, 30 galls.

Used for the ironwork of carriages, and other nice purposes.

(3. BLACK j.a.pAN, BITUMINOUS VARNISH.)--_a._ From Naples asphaltum, 50 lbs.; dark gum anime, 8 lbs.; fuse, add of linseed oil, 12 galls.; boil as before, then add of dark gum amber, 10 lb., previously fused and boiled with linseed oil, 2 galls.; next add of driers q. s., and further proceed as ordered in No. 2. Excellent for either wood or metals.

_b._ From burnt umber, 8 oz.; true asphaltum, 4 oz.; boiled linseed oil, 1 gall.; grind the umber with a little of the oil; add it to the asphaltum, previously dissolved in a small quant.i.ty of the oil by heat; mix, add the remainder of the oil, boil, cool, and thin with a sufficient quant.i.ty of oil of turpentine. Flexible.

4. (BRUNSWICK BLACK.)--_a._ To asphalt, 2 lbs., fused in an iron pot, add of hot boiled oil, 1 pint; mix well, remove the pot from the fire, and, when cooled a little, add of oil of turpentine, 2 quarts. Used to blacken and polish grates and ironwork. Some makers add driers.

_b._ From black pitch and gas-tar asphaltum, of each 25 lbs.; boil gently for 5 hours, then add, of linseed oil, 8 galls.; litharge and red lead, of each 10 lbs.; boil as before, and thin with oil of turpentine, 20 galls.

Inferior to the last, but cheaper.

=Varnish, Body.= _Prep._ 1. From the finest African copal, 8 lbs.; drying oil, 2 galls.; oil of turpentine, 3-1/2 galls.; proceed as for AMBER VARNISH. Very hard and durable.

2. Pale gum copal, 8 lbs.; clarified oil, 2 galls.; dried sugar of lead, 1/2 lb.; oil of turpentine, 3-1/2 galls.; proceed as before, and mix the product, whilst still hot, with the following varnish:--Pale gum anime, 8 lbs.; linseed oil, 2 galls.; dried white copperas, 1/4 lb.; oil of turpentine, 3-1/2 galls.; the mixed varnishes are to be immediately strained into the cans or cistern. Dries in about 6 hours in winter, and in about 4 hours in summer. Used for the bodies of coaches and other vehicles.

=Varnish, Bookbinder's.= _Prep._ Take of pale gum sandarach, 3 oz.; rectified spirit, 1 pint; dissolve by cold digestion and frequent agitation. Used by binders to varnish morocco leather book-covers. A similar varnish is also prepared from very pale sh.e.l.l-lac and wood naphtha.

=Varnish for Boots and Shoes.= See BOOTS and SHOES.

=Varnish, Cabinet-maker's.= French polish is occasionally so called.

=Varnish, Carriage.= _Prep._ 1. (SPIRIT.) Take of gum sandarach, 1-1/4 lb.; very pale sh.e.l.l-lac, 3/4 lb.; very pale transparent resin, 1/2 lb.; rectified spirit of 8221 (64 o. p.), 3 quarts; dissolve, and add of pure Canadian balsam, 1-1/2 lb. Used for the internal parts of carriages, &c.

Dries in 10 minutes or less.

2. (OIL.)--_a._ (Best pale.) Take of pale African copal, 8 lbs.; fuse, add of clarified linseed oil, 2-1/2 galls.; boil until very stringy, then add of dried copperas and litharge, of each 1/4 lb.; again boil, thin with oil of turpentine, 5-1/2 galls.; mix, whilst both are hot with the following varnish, and immediately strain the mixture into a covered vessel:--Gum anime, 8 lbs.; clarified linseed oil, 2-1/2 galls.; dried sugar of lead and litharge, of each 1/4 lb.; boil as before, thin with oil of turpentine, 5-1/2 galls. Dries in 4 hours in summer, and 6 in winter. Used for the wheels, springs, and carriage parts of coaches, and other vehicles, and by house painters, decorators, &c., who want a strong, quick-drying, and durable varnish.