Part 95

Brass or Copper.--(_o_) Mix together 1 oz. oxalic acid, 6 oz. rottenstone, and ½ oz. gum arabic; all these are to be finely powdered. Then add 1 oz. sweet-oil and sufficient water to form the mixture into a paste. Apply a small portion to the article to be cleaned, and rub dry with a flannel or washleather.

Bronze.--(_a_) For cleaning bronze statues, when blackened by smoke and soot, wash with plenty of clean water, accompanied with mechanical friction. Even this simple treatment is undesirable; because the friction, however slight, accompanying the washing, destroys, or tends to destroy, the sharpness of the outlines; and the sulphurous and sulphuric acids of the prevailing smoke rapidly corrode the surface of any bronze statue which is constantly being washed. For these reasons, the Nelson monument at Liverpool, was left untouched when it was re-erected, after the building of the new Exchange surrounding it. It has been a matter of much debate whether the soot-blackened surface of a bronze statue is not more pleasing to the eye, than the metallic lustre of a new, or newly-cleaned statue. (_b_) Weber finds that a dilute solution of caustic alkalies removes overlying dirt, and allows the green patina to become visible. Where the metal was not originally oxidised, the alkali simply cleanses it, and does not promote any formation of green rust. (_c_) By dipping fustian in soluble glass, and washing it with soap directly afterwards, we get a fabric largely impregnated with silica, which will be found very well adapted for cleaning bronzes, &c. Samples of the material were in the Vienna Exhibition, and attracted some notice. (_d_) The method of restoring a bronze tea-urn turned black in parts will depend, to a great extent, on the metal and the colour. Clean the surface, first of all, with whiting and water, or crocus powder, until it is polished; then cover with a paste of graphite and crocus, mixed in the proportions that will produce the desired colour. Heat the paste over a small charcoal fire. If the bronzing has been produced by a corrosive process, try painting a solution of potassium sulphide over the cleaned metal. There are many recipes for bronzing, and it is impossible to say which is suitable. The bronzed surface may be polished; but it cannot be bright unless the surface of the metal itself is polished, and then covered with transparent lacquer to preserve the brightness.

Coins.--Coins can be quickly cleansed by immersion in strong nitric acid, and immediate washing in water. If very dirty, or corroded with verdigris, it is better to give them a rubbing with ½ oz. pure potash bichromate, 1 oz. sulphuric acid, 1 oz. nitric acid; rub over, wash with water, wipe dry, and polish with rottenstone or chalk. (Lyle.)

Copper Electros.--Copper electros should be well cleaned after working, as the ink between the fine lines in time generates acids, which destroy the electro. For this purpose turpentine and the brush are employed; others also recommend the electros to be afterwards well rubbed with an oil as free from acid as possible. Should the ink be so dried up as to resist it, creosote should be applied, and the electros treated with the brush.

Copper Vessels.--Use soft-soap and rottenstone, made into a stiff paste with water, and dissolved by gently simmering in a water-bath. Rub on with a woollen rag, and polish with dry whiting and rottenstone. Finish with a leather and dry whiting. See also _Brass_.

Gas Chandeliers.--Very few chandeliers are gilt; they are burnished and lacquered with yellow lacquer. Proceed as follows, whether gilt or lacquered: Take the chandelier to pieces, and boil in strong soda lye for a few minutes; brush over with a soft brush, pass through a strong solution of potassium cyanide (deadly poison), wash through a tubful of boiling water, dry in clean sawdust, wipe up bright with a washleather, and relacquer.

Gilt Mountings.--Gilt mountings, unless carefully cleaned, soon lose their lustre. They should not be rubbed; if slightly tarnished, wipe them off with a piece of Canton flannel, or what is better, remove them if possible, and wash in a solution of ½ oz. borax dissolved in 1 lb. water, and dry them with a soft linen rag; their lustre may be improved by heating them a little, and rubbing with a piece of Canton flannel.

Gold.--(_a_) To remove the brown tarnish from coloured gold, take a piece of tissue-paper damped in liq. ammoniæ, gently rub the gold till the tarnish disappears, then wash off carefully with soft brush, soap, and water, dry in sawdust or before the fire; if this is not sufficient, entrust the article to a jeweller. (_b_) Mix a little rouge and spirits of wine together, and apply to the jewellery with a rather stiff brush, and turn the brush round and round--not to brush as if to polish, but rather tickle it and pat it with the hair of the brush; but be sure to keep the brush wet with the mixture. After you have got the tarnish off, wash it out with soap and boiling water, and dry in box-dust. Take care of any stones with foil behind. (_c_) Rub with a piece of tissue-paper, screwed up and wet with the tongue. This will often do it; if not, re-colour it. (_d_) A weak solution of potassium cyanide will clean gold braid. Use with small sponge, and wash off with clean water. Strength, say 10 or 15 gr. to the oz. of water. Care should be taken that the solution does not get into any cuts or wounds, as it is very poisonous. The strength of the solution would greatly depend on the condition of the lace. It can be made stronger if necessary. (_e_) A solution of 20 dr. lime chloride, 20 dr. soda bicarbonate, and 5 dr. common salt, in 5¼ pints distilled water, is prepared and kept in well-closed bottles. The article to be cleaned is allowed to remain a short time in this solution (which is to be heated only in the case of very obstinate dirt), then taken out, washed with spirit, and dried in sawdust. (_Chem. Cent. Blatt._)

Iron and steel.--(_a_) Take a spongy piece of fig-tree wood and well saturate it with a mixture of sweet-oil and finely powdered emery, and with this well rub all the rusty parts. This will not only clean the article, but will at the same time polish it, and so render the use of whiting unnecessary. (_b_) Bright iron or steel goods (as polished grates and fire-irons) may be preserved from rust in the following manner. Having first been thoroughly cleaned, they should be dusted over with powdered quicklime, and thus left until wanted for use. Coils of piano-wire are covered in this manner, and will keep free from rust for many years. (_c_) Dissolve ½ oz. camphor in 1 lb. hogs’ lard, and take off the scum; then mix with the lard as much black-lead as will give the mixture an iron colour. Rub the articles all over with this mixture, and let them lie for 24 hours; then dry with a linen cloth, and they will keep clean for months. (_d_) Table knives which are not in constant use should be put in a case containing a depth of about 8 in. quicklime. They are to be plunged into this to the top of the blades, but the lime must not touch the handles. (_e_) Steel bits that are tarnished, but not rusty, can be cleaned with rottenstone, common hard soap, and a woollen cloth. (_f_) Removing paint from iron.--After a number of experiments, it has been found that a paint-softener made of 1 lb. lime to 4 lb. potash and 6 qt. water works better than any other proportions.

Plate Powders.--(_a_) Equal parts precipitated iron subcarbonate, and prepared chalk. (_b_) An impalpable rouge may be prepared by calcining iron oxalate. (_c_) Take quicksilver with chalk, ½ oz., and prepared chalk 2 oz., mix them. When used, add a small quantity of spirits of wine, and rub with chamois leather. (_d_) Put iron sulphate into a large tobacco pipe, and place it in a fire for ¼ hour, mix with a small quantity of powdered chalk. This powder should be used dry. (_e_) The following makes a liquid polish for silver plate--3 to 4 dr. potassium cyanide, 8 to 10 gr. silver nitrate, and 4 oz. water; apply with a soft brush, wash the object thoroughly with water, dry with a soft linen cloth, and polish with a chamois skin. (_f_) Take 2 oz. hartshorn powder and boil it in 1 pint water; soak small squares of damask cloth in the liquid, hang them up to dry, and they will be ready for use, and better than any powders. (_g_) Add by degrees 8 oz. prepared chalk in fine powder to a mixture of 2 oz. spirits of turpentine, 1 oz. alcohol, ½ oz. spirits of camphor, and 2 dr. aqua ammonia; apply with a sponge, and allow it to dry before polishing. (_h_) Mix together 1 oz. fine chalk, 2 oz. cream of tartar, 1 oz. rottenstone, 1 oz. red-lead, and ¾ oz. alum; pulverise thoroughly in a mortar. Wet the mixture, rub it on the silver, and, when dry, rub off with a dry flannel, or clean with a small brush. (_i_) An excellent preparation for polishing plate may be made in the following manner:--Mix together 4 oz. spirits of turpentine, 2 oz. spirits of wine, 1 oz. spirits of camphor, and ½ oz. spirits of ammonia. To this add 1 lb. whiting, finely powdered, and stir till the whole is of the consistency of thick cream. Use this preparation with a clean sponge, cover the silver with it, so as to give it a coat like whitewash. Set the silver aside till the paste has dried into a powder; then brush off, and polish with a chamois leather. A cheaper kind may be made by merely mixing spirits of wine and whiting together.

Silver and Plated Goods.--(_a_) East Indian jewellers never touch silver ware with any abrasive substance, but use, instead of polishing paste, &c., slices of lemons; the goods to be cleaned are well rubbed with these, and then left in a pan for a few hours, covered with slices. For delicate jewellery, a large lime is cut in half, the article inserted, the two halves applied together and tied up for some hours; the article is then washed in several waters, placed in a pan of nearly boiling soapsuds, stirred about, rinsed, and dried on a metal plate, the smooth parts being gently rubbed with wash-leather, if required. (_b_) Potassium cyanide solution (rather weak) dissolves off the dirty surface gradually, but great care is required. (_c_) Green tamarind pods (potash oxalic) are greater detergents for gold and silver than lemons, and are often employed for the purpose of removing stains, firemarks, &c. (_Boston Journal of Chemistry._) (_d_) Eisner states that a polish equal to that obtained by the use of the finest plate powder, can be produced by simply cleaning the silver in water in which potatoes have been boiled. (_e_) Dead or engraved silver goods should never be cleaned with plate powder, but be washed out with a soft brush and some strong alkali, and well rinsed afterwards. When the dead or frosted parts are quite dry, the polished parts are carefully cleaned with powder. (_f_) The following directions are given by a silversmith in Christiania:--Silver filagree work is best cleaned by the application of spirit of ammonia by means of a soft brush, and afterwards thoroughly washing in soft-soap and warm water, and rinsing in clean warm water, and quick drying by linen rags, blotting-paper, or some similar clean absorbent. Should this method, after several repetitions, cease to have the required effect, the article will have to be sent to a silversmith to be heated and boiled in acid. The best mode of preservation is to wrap the article in tissue paper before placing it in the case. (_g_) The simplest and cleanest substance for cleaning silver articles is, according to Professor Davenport, soda hyposulphite. It acts quickly, and is inexpensive. A rag or a brush, moistened with a saturated solution of the salt, cleanses even strongly oxidised silver surfaces in a few seconds, without the application of any polishing powder. (_h_) Mix 8 oz. prepared chalk, 2 oz. turpentine, 1 oz. alcohol, 4 dr. spirits of camphor, and 2 dr. liquor of ammonia. Apply this mixture to the article with a sponge, and allow to dry before polishing. (_i_) Dissolve 12 oz. potassium cyanide in 1 qt. water; dip in this solution, and brush it with a stiff brush until clean; then wash and dry. (_j_) A paste composed of washed whiting, precipitated magnesia carbonate, and precipitated iron peroxide. (_k_) Gin. (_l_) Apply whiting mixed with sweet oil on a shammy. (_m_) Take 2 qt. water, ½ oz. hartshorn, and 1 oz. whiting, and boil the whole together. While boiling, put as many of the silver or plated articles into the vessel as it will conveniently hold, and let remain for 5 minutes; withdraw, and leave to dry. Polish with clean linen or woollen rags, which, after being soaked in the above-named liquor, have been well wrung. Finally rub with a clean soft leather. (_n_) The ink eraser sold by stationers has the property of cleaning and brightening silver and gold mountings, such as meerschaum pipe fittings, pencil-cases, watch-cases, &c. (_o_) Cut some flakes of white curd soap, and put them into a saucepan of water to simmer; sew the ornaments up in a muslin bag, and place in the liquid for about 10 minutes whilst on the fire.

Tarnished Silver Lace.--(_p_) Sponge over with a weak solution of potassium cyanide. (_q_) Dab over with a cream of heavy magnesia and water, allowing this to dry, and then brushing it off with a soft-haired brush.

Zinc Vessels.--Zinc articles, if small, can be cleaned by being pickled in spirits of salt (hydrochloric acid) with water added, till the articles are nicely cleaned, in about 3 minutes, without being too strongly attacked, then washed and dried. Large articles like refrigerators are cleaned by being rubbed with a swab, dipped in raw spirits, then washed with water, and finished with whiting.

_Paint._--(_a_) Paint should be more often swept than scrubbed, for too frequent scrubbing causes it to decay. Use as little soap as possible, and wash it off with plenty of clean water to prevent discoloration. To clean paint that has not been varnished, put upon a plate some of the best whiting; have ready some clean warm water, and a piece of flannel, which dip into the water and squeeze nearly dry; then take as much whiting as will adhere to it, apply it to the paint, when a little rubbing will instantly remove any dirt or grease; wash well off with water, and rub dry with a soft cloth. Paint thus cleaned looks equal to new, and, without doing the least injury to the most delicate colour, it will preserve the paint much longer than if cleaned with soap, and it does not require more than half the time usually occupied in cleaning.

(_b_) When painted work is badly discoloured, put 1 tablespoonful ammonia water into 1 qt. moderately hot water, and with the aid of flannel, wipe off the surface. Rubbing is not necessary.

(_c_) Take 1 oz. pulverised borax, 1 lb. shavings of best brown soap, and 3 qt. water. Put the soap and borax into the water, allow it to simmer until all the soap has been dissolved, stir it frequently, but do not allow it to boil. Apply it to the paint on a piece of old flannel, and rinse with clean water.

(_d_) Dissolve ½ oz. glue, and a bit of soft-soap the size of a walnut, in about 3 pints warm water, and with a well-worn whitewash brush well scrub the work, but not sufficient to get off the paint; rinse with plenty of cold clean water, using a washleather; let it dry itself. Work done in this manner will often look equal to new.

(_e_) First take off all the dust with a soft brush and pair of bellows. Scour with a mixture of soft-soap and fullers’ earth, and use lukewarm water. If there are any spots which are extra dirty, first remove these by rubbing with a sponge dipped in soap and water. Commence the scouring at the top of the door or wainscot, and proceed downwards; dry with a soft linen cloth. When cleaning paint, it is always better to employ two persons, one to scour and the other to rub dry.

Paint-brushes.--(_a_) To soften brushes that have become hard, soak them 24 hours in raw linseed oil, and rinse them out in hot turpentine, repeating the process till clean. (_b_) Wash in hot soda and water and soft-soap.

_Paper and Books._--(_a_) The amateur book-cleaner had better begin to practise on some worthless volume, until he acquires the necessary skill. All traces of lime, &c., used in the cleaning process must be removed from the book, else in time it may be completely destroyed. The first thing to be done in a book that wants washing, is to cut the stitches and separate the work into sheets. Then a glance may be taken for the separation of those leaves or sheets which are dirty from those which have stains of ink or oil. The dirty leaves are now placed in a bath composed of ¼ lb. lime chloride and the same quantity of soda to about 1 qt. water. These are left to soak until the paper has regained its proper tint. The pages are now lifted out tenderly into a second bath of cold, and if possible running, water, where they are left at least 6 hours. This removes all traces of lime. The paper, when thoroughly dried by exposure, must be dipped into a third bath of size and water, and again laid out to dry. This restores the consistency of the paper. Pressure between printers’ glazed boards will then restore smoothness to the leaves. The toning of the washed leaves in accordance with the rest of the book is a delicate process, which requires some experience. Some shag tobacco steeped in hot water will usually give the necessary colouring-matter, and a bath in this liquid the necessary tone.

The process described above may do for water-stains; but if the pages are dirted by grease, oil, coffee, candle-droppings, or ink, different treatment will be required. Dilute muriatic acid with 5 times its bulk of water, and let the oil-stained pages lie in the liquid for 4 minutes--not longer. Then remove, and wash, as before, in cold water. If the grease is a spot in the middle of a page, place between 2 sheets of blotting-paper, or cover with powdered French chalk (the blotting-paper is preferable), and pass a hot iron over the place. This will melt the grease, which is immediately soaked up by the chalk or paper.

For dirty finger-marks, the following is recommended: Cover the mark with a piece of clean yellow soap for 2 or 3 hours, then wash with a sponge and hot water, and dip the page in weak acid and water. Give another bath of hot water, and then thoroughly cleanse with cold water. To remove ink-stains, dip the page in a strong solution of oxalic acid, then in a solution of 1 part muriatic acid and 6 water, after which bathe in cold water, and allow to dry slowly. Vellum covers which need cleaning may be made almost equal to new by washing with a weak solution of potash binoxalate, or, if not much soiled, warm soap and water. Grease may be removed from the covers of bound books by scraping a little pipe-clay, French chalk, or magnesia over the place, and then ironing with an iron not too hot, else it will discolour the leather. (_Publishers’ Circular._)

(_b_) Press powdered fullers’ earth lightly upon the greasy spot, and allow it to soak out the grease.

(_c_) Hannett says the spots may be removed by washing the part with ether, chloroform, or benzine, and placing between white blotting-paper, then passing a hot iron over.

(_d_) A more expeditious, and thought by some, the best way, is to scrape fine pipe-clay, magnesia, or French chalk on both sides of the stain, and apply a hot iron above, taking great care that it is not too hot.

(_e_) After gently warming the paper, take out all the grease you can with blotting-paper, and a hot iron, then dip a brush into essential oil of turpentine, heated almost to ebullition, and draw it gently over both sides of the paper, which must be kept warm. Repeat the operation until all is removed, or as often as the thickness of the paper may render necessary. When all the grease is removed, to restore the paper to its former whiteness, dip another brush in ether, chloroform, or benzine, and apply over the stain, especially the edges of it. This will not affect printers’ or common writing ink.

(_f_) Lay on a coat of indiarubber solution over the spot, and leave it to dry. Afterwards remove with a piece of ordinary indiarubber. Any operation with ether, chloroform, or benzine, should never be conducted by candle-light, as their vapour is apt to kindle even at several feet from the liquid. (_d_) will remove grease from coloured calf, even if the spot be on the under side of the leather; it may thus be clearly drawn right through.

(_g_) Apply a solution of pearlash (in the proportion of 1 oz. pearlash to 1 pint water) to oil-stained drawing-paper.

_Parchment and Vellum._--(_a_) Immerse in a solution of acetic acid, and gently rub the stained parts while wet on a flat board with lump pumice, then bleach with lime chloride. This process was recommended in the _English Mechanic_. It is not very successful, but it makes it white enough for bookbinding. It has, however, the objectionable qualities of not making the parchment flexible, and when dried it is as hard as a board, and it has no gloss like the virgin parchment. On no account must the parchment be washed in very hot water, or held before a fire, as it will shrivel up in a most provoking manner.

(_b_) Benzine applied with a sponge. It will remove almost every stain, and does not destroy the texture in the least.

_Pictures, Prints, and Frames._--Pictures.--(_a_) Remove the works from their frames, and first of all examine the surface of each separately and with care. Then, if there are no cobweb cracks, no cockled-up edges of bits of paint likely to peel off, and no unburst bubbles of colour, take an old soft cloth, and some white of egg, and wash the surface, a square inch at a time, with a spiral motion of the hand, not pressing too heavily. If there is much dirt, make a basin of bread, treacle, and new milk with a trifle of turpentine in it, and wash with soft flannel and sponge; after, use white of egg. If mildew from damp walls has attacked the canvas, and even the surface, let a committee of artists be called; there are so many varieties of this form of injury, it is well to understand the particular case. If coal gas, foul air, or other pollution is suspected of having injured the varnish, an artist chemist, learned in varnishes of the different schools, must prescribe; but if the surface is injured, or the colour scales off, no amateur can repair the crack; and in every case, before returning the well-cleaned and well-rubbed surfaces to their frames, let good plate glass be securely fastened over each to prevent future injury.

(_b_) Pictures may be cleaned by rubbing the thumb over the painting moistened with saliva, or by a raw potato cut in half and rubbed evenly over the picture.

(_c_) Dissolve a little common soda in urine, then add a grated potato and a little salt; well rub this over the paintings till clean. Wash off in spring water, and dry with a clean cloth.

(_d_) First rub the picture well with good whisky, which will make the varnish come off in froth, then wash well with cold water, and when dry varnish again; this will restore the picture to its original colour unless very old. Keep the picture covered from dust till the varnish is dry.