Although it would be folly to suggest that a mere layman dare risk any extensive cleaning or restoring of valuable pictures, there are one or two things which he might do to improve the appearance of his pictures. First of all, if superficial dust and dirt coats an old painting—oil-painting, of course —there is nothing like good soap and warm water, applied with a sponge, for bringing it up. If, however, the dirt is of long standing duration, it should be cleaned with pure methylated spirit. A very soft piece of lint or cotton wool should be used: the picture should be removed from the frame and laid down face upwards. A little spirit should be poured on (first on an inconspicuous part, to see the effect), and with the rubber, short staccato rubs should be given with a circular motion. This must be done very tentatively until the effect is noted, as, if the picture is not really old, the paint may not have permanently set, and the spirit may dissolve it. If, however, the picture is known to be, say, over a couple of hundred years old, there need be no fear of the consequences—nothing in the world will remove the paint. After thoroughly cleaning with spirit, the picture should be left to dry for a few hours, and then it may be coated with a coat of picture varnish (Mahl-firnis), which may be purchased from dealers in artists’ requisites.
If an old master develops a condition of what is known as ‘’ frosty varn ish’ ‘•—th e who 1 e picture is obliterated through the varnish becoming opaque—an experiment may be attempted which we have tried with success; rub it well with strong ammonia; this is admittedly a risky method, but if the picture is really old, it is unlikely to do it any harm ; if it is not, it is not likely to have developed ‘frosty varnish.’ O? course, the safest plan is to take a valuable picture to a restorer for cleaning. Should a picture become damaged, it will require restoring or relining, and this must be done by an expert.
Should the stretchers become broken, the picture should be taken from the frame, and the stretchers very carefully removed; a new piece of wood may then be let in to replace the fractured batten, and the canvas tacked on in the same place as before. Be careful not to damage the painting.
Print restoring is a very delicate operation. Ordinary damp or mildew must be treated by an expert, but should one or two worm holes appear on an unimportant part of the print, the ingenious amateur may remedy as follows: Carefully remove the print from its mount. Obtain a few tiny fragments of paper nearly approximating in consistency to that on which the print is engraved, and chew them into a machi. When reduced to a thorough pulp, mix with dilute seccotine, roll into tiny spills small enough to insinuate through the worm holes without enlarging them; thrust them through the holes, and, laying the print on a clean glass bed, hammer flat with a light tack hammer covered with chamois leather. After hammering, the spill will appear as a small hump on either side of the print. Leave till dry. Now comes the most ‘ticklish ‘’ part of the operation : lay a safety razor (a very keen one) on the print and remove the dried machi level with the surface of the print on either side—leaving none except that which stops the holes. After this, any missing lines in the engraving may be etched in with Indian ink and a very fine pen. If the print is valuable amateurs should not attempt this, but leave it to an expert. He could, however, find worse ways of occupying his time than by practising on valueless prints. He must remember, however, that an unmounted print is a very flimsy article, and if he is incapable of delicate workmanship he had much better leave well alone.