The larger the violin is, the weaker should be the strings. The notion that a half-sized violin should be thin-stringed, is quite erroneous, it should, on the contrary, have strings as strong as a full-sized violin, for owing to the shorter length, the strings, if they be a weak set, become too loose and do not give a true sound, and offer insufficient resistance under the pressure of the bow.
XX. THE VARNISH.
There has been for many years a warm and to a certain extent undecided discussion going on, as to whether the varnishes used by Italian violin makers were oily and slow-drying ones or spirit varnishes. To investigate this matter still further, and to arrive at a correct decision, will have to be left to the future.
I am, however, of the opinion that the old masters made use of spirit or turpentine-oil until the middle of last century, but never of linseed-oil or turpentine-oil varnish, as has been often asserted.
My opinion is supported by the following fact. In the year 1860 I had the good fortune to buy a real Nicolas Amati lute which, although very much knocked about, still retained a thick varnish of a most beautiful gold colour. For my information I took the varnish off, in order to submit it to the analysis of a clever chemist who, being a talented amateur violinist and also a pupil of Spohr, showed great interest in the matter and communicated to me, as the result of his investigations, this fact that among the quantity of varnish which I had placed at his command, there was not a trace of evidence which could lead to the conclusion that linseed-oil varnish had been employed. In my own researches I found that the varnish was immediately dissolved in spirit of only 90 per cent., while in oil of turpentine and linseed-oil it was scarcely affected, and by boiling only a small portion was removed. Again, it is not probable that Stradivarius, in whose workshops about 3000 violins were constructed, would have employed linseed-oil varnish, seeing that it would have required, in each case, six months for the violin to get thoroughly dry.
There are many resins which can be dissolved in spirit or oil of turpentine and used as a varnish, but the preference is generally given to spirit-varnish, as it dries more quickly. If the spirit or turpentine-oil has evaporated, only the resin remains.
The greatest attention must be paid to the relative hardness of the resin and the wood, for both should be of equal density. Hard resin hinders the vibration of the wood, and consequently the quality of tone suffers.
In my opinion shellac is quite useless for varnishing, it being much too hard, but nevertheless it has been employed from 1770 until the present day, in spite of the fact that the best Italian instrument might be completely ruined by being varnished with it. In all Italian instruments the old varnish is always very porous and soft, and can easily be dissolved by the application of spirit, while, on the contrary, it requires great labour to effect the same with turpentine-oil.
Many people affirm that the art of mixing the old Italian varnish which so charms us with its brilliancy and transparency, is no longer known, in fact that it is for ever lost. I am, however, of a different opinion and maintain that our modern varnishes are quite equal to the old, but what we have until now been unable to produce scientifically, is the golden-brown underground which the wood of older violins has acquired through age and other influences. The proof of this I have practically demonstrated by varnishing old instruments with new varnish, in imitation, with such success as to arouse the wonder of connoisseurs, the varnish being quite as transparent and brilliant-coloured as that used for violins in the last century.
To one other point I should like to call the attention of the reader. In repairing old instruments of the time of Stradivarius, I have found that an extraordinary cleanliness and lustre is obtained by rubbing them with fine glass-paper, which is not the case with Tyrolean and German violins of the same period. At a later period this peculiarity was not met with so frequently and from the year 1750 not at all. This fact I primarily attribute to the action of the resin on the wood, being also of opinion that the fine dust of the same gets firmly embedded in the pores of the wood, and in this way, in course of time, a more or less thick coating is formed.