Georges Foucher

“ Rosins when pure are usually without taste or odour—white, yellow, or brown in colour. They are insoluble in water but can be dissolved to a certain extent in alcohol, ether and various oils. Oxygen has not much effect on them with the exception of the copals.
It is very difficult to obtain a pure rosin, it is nearly always a mixture of different rosins, each having separate properties.
One great difficulty to be met with in the making of varnish is that rosins are not always of the same degree of hardness. ”

“ Copal from Sierra Leone is white and elastic and is especially adapted to be mixed with other varieties in the manufacture of varnish. Asia supplies us with many copals but these are not genuine Asiatic products, but are sent from Africa, mixed in Asia and from thence exported to Europe.
The real copals of Asia are divided, as are the others, into hard and tender. The best African copals are the hardest, they much resembling amber. They are easily distinguished from it, however, as they will readily melt if brought into contact with the flame of a candle. ”

“ A good varnish must, in spite of its adhesive character, allow the wood to vibrate freely and should itself vibrate as an integral part of the instrument, and it should not in any way affect the tone possessed by the violin previous to its having been varnished. ”

“ It was probably not a secret at one time, but each maker in his endeavour to surpass his rival tried to improve upon what we recognise now to have been as near perfection as possible, so that instead of attaining the ideal they gradually fell away from their high standard until the original process has been buried in the innumerable and vain attempts to supersede the first and most successful efforts. ”

“ Alcohol is a produce composed of carbon, hydrogen and oxygen; it is usually diluted with water in various quantities, by which its strength is determined.
Alcohol is or can be extracted from an innumerable variety of materials, in fact, anything containing sugar in any proportion can, by the process of fermentation, be used for the production.
The materials most usually employed are wines, roots, seed, etc. Alcohol is seldom obtained pure for numerous reasons, the principal being that it absorbs with great avidity the moisture contained in the atmosphere. ”

“ When oil has been kept for a long period it loses many of its impurities, and when buying it always enquire as to the age, as the older it is the better.
With the aid of chemistry we are able to render oil siccative in a very short time. The process need not be entered into fully at present, but the most usual method is to heat it in the presence of various metallic oxydes. ”

“ Others again have from a purely mercenary motive used such materials in the composition of their varnish that were not of the best quality, and which, in the course of time, have deteriorated to such an extent that at the present time varnishes are much below the standard set by the examples left us by the great masters of other days. ”

“ The distinctive character of Essential Oils is that while it will mark a piece of paper in a greasy fashion, the mark is not permanent, but will in a certain time entirely disappear, and, under the influence of heat, disappear more rapidly. ”

“ Two coats of oil varnish are sufficient.
To colour essence of turpentine dissolve in it some dragon's blood, etc.
Be very careful in the manipulation of the various ingredients when they have to be heated. Accidents will occur if proper care is not taken. Whenever possible the heating should be done out of doors. ”

“ Add to the gum to be dissolved a small quantity of broken, not powdered, glass. The glass will get mixed with the gums and prevent it forming a solid mass, thus enabling the solvent to act more promptly. ”

“ Correctly speaking it is not a pure rosin, but a mixture of rosins each having separate degrees of solubility.
It also contains some oils.
Hard copals mostly come from Zanzibar. Those known as animes reach us from Bombay and also Madagascar. The semi-hard are obtained from Africa and reach us in different forms. Those coming from Angora are in the form of reddish balls. ”

“ It is also obtained in small quantities from India, America and Australia.
It is a hard substance which, after being subjected to the process of melting, becomes partially soluble in spirit and to a higher degree in ether and essence of turpentine. ”

“ Fill a bottle with shellac, broken glass and spirit in equal proportions. Roll and shake bottle from time to time during 12 hours. Boil in hot water bath. Dilute to substance of thin glue, and filter on wool. ”

“ Dissolve in alcohol 1 oz.„ Prepared Amber.Mastic.
Add broken glass
Proceed as for Example No. 2.
After dissolution of the rosins add 1 oz. of turpentine (liquid) .
Amber and Turpentine Varnish.
No. 7.
Place in a bottle 4 oz. Prepared Amber.Sandarach.
Place in a bottle 4 oz.„ Prepared Amber.Mastic.
Place in a bottle 4 oz.„ Prepared Amber.Animé.
Place in a bottle 2 oz.„ Prepared Amber.
Place in a bottle and some broken glass.
Bring gently to melting point (in hot water bath) . When melted add 12 oz. of turpentine (liquid) . Continue to heat until completely dissolved. ”