7. The string gauges

To discover the gauges of early strings and to establish their working tensions, the contemporary documents and treatises must of course be considered (as researchers have done in the past), but I would propose doing it from a slightly unorthodox viewpoint: our main point of departure must be the information (both direct and indirect) that can be derived from the string makers themselves. This would seem the right approach because, whatever the treatises and violin manuals said, in the end it was the string makers who established (or rather imposed) the commercial diameters.

The diameters are in turn unseparably linked to the number of guts used to make a string. Obviously a specific number of guts corresponds not to a specific gauge but to a mean value, with a degree of oscillation on either side: guts, being natural products, are never exactly the same size. This is a fundamental consideration that needs immediate clarification. Unlike today, when mechanical processes of rectification allow makers to produce a wide variety of progressively scaled string sizes (e.g.: 0.60, 0.62, 0.64 mm, etc.), until the first decades of the twentieth century the ultimate caliber of the strings was determined almost exclusively by the number of guts used to make a string of a given diameter. As certain documents show (56) , the strings on sale were distinguished not by their diameters in mm but by the number written on the packet which served to specify how many guts were used to make the strings inside the box.

String makers had always endeavoured, to the best of their ability, to standardize the quality and type of gut used: by using material from lambs of the same age, race and geographic area and by selecting the guts carefully before combining them. Nonetheless, there was inevitably a margin of uncertainty or variability in the diameter of the finished product. Nor could this be remedied by manual polishing (which lacks the precision of mechanical rectification), for there was a strong risk of making an untrue string, owing to the real difficulties of achieving perfect rotundity in the gut, with the added risk of excessive damage to the surface fibers. In fact, to avoid this risk, in late nineteenth century violin first strings were usually not polished at all (57).

The diameter of a string made of three lamb-guts, for example, could thus be represented by the Gaussian curve. And the same, of course, applies to strings of other gauges obtained by combining different numbers of fresh guts. The skill of a good string maker consisted in being able to manufacture a box of strings (which would be marked, for example, as "3") with a low oscillation around the mean diameter and to reproduce this mean diameter in different batches of strings made at different times. Such abilities were understandably highly appreciated by musicians. The mark of a good maker was therefore the achievement of a narrow Gaussian curve for the string diameters.

An idea of the diameter variance of strings made with the same number of guts can perhaps be deduced from the three degrees of tension George Hart recommends for a violin first string: they range from 0.65 to 0.73 mm. Inevitably, with the increase in the number of guts twisted together (to obtain thicker strings), there is a corresponding decrease in diameter variance, explained by a "mediation" effect arising when a larger number of guts are used. With increasing numbers, we also note smaller differences in gauge between adjacent numbers (for example, between a string of ten guts and one of eleven).

Let us now examine the historical information from the string makers.

-The first record of Italian string making known to us would seem to be De Lalande's above-mentioned Voyage en Italie, a work that contains very interesting information on the most important string makers of the Abruzzi (58). Among them are included Angelo and Domenico Antonio Angelucci, the owners of an important string factory in Naples in the early eighteenth century; Domenico Antonio died in 1765 (59). From this document we learn that making a violin first string requires three whole lamb guts of eight to nine months of age; the bottom string — i.e. the third, not the fourth which was, as we shall see below, overspun — needs seven guts (60). The use of three guts in the making of a first string is also mentioned in a do-it-yourself recipe dating probably from the beginning of the eighteenth century (61).

The same tendency — that of using three, sometimes four, whole guts for a violin E string — remains constant throughout the nineteenth century (62).

It even appears in Maugin and Maigne's manual, which cites information from the French stringmaker of Neapolitan origin Henry Savaresse: "Les chanterelles se composent de 4, 5 ou 6 fils, selon la grosseur du boyau, et chaque fil est formé d'une moitié de boyau divisé dans sa longueur. Les ‘mi’ de violon ont de 5 à 4 fils pleins, mais très fins. Les ‘la’ en ont le meme nombre, mais plus forts. Quant aux ‘re’, ils en ont de 6 à 7 pleins" (The chanterelles are made of four, five or six strands, depending on the thickness of the gut, and each strand consists of a half gut cut lengthwise. The violin E strings have from three to four whole, but very thin, threads. The A strings have the same number, though stronger ones. As for the D strings, they have from six to seven full strands) (63). This is confirmed by Philippe Savaresse, who writes: "On a longtemps attribué la supériorité des cordes de Naples aux secrets de fabrique, plus tard on l’a attribuée à la petite espèce de moutons qui permettait de faire les chantarelles à trois fils" (For a long time the superiority of Neapolitan strings was attributed to manufacturing secrets; later it was attributed to a type of sheep that allowed one to make chanterelles with three strands); further on he adds: "La chantarelle ayant trois fils, si les autres cordes sont faites avec les mêmes intestins, la seconde aura 5 ou 6 fils et la troisième 8 et 9“ (With a chanterelle of three strands, if the other strings are made with the same gut, the second will have five or six strands, the third eight and nine) (64). Clearly, when the gut is split in half, twice as many pieces are needed to make a string. One can therefore conclude, with a certain margin of certainty, that a violin chanterelle was universally made by the Italian string makers – but also by the French and Germans – from three (sometimes four, if thinner) whole guts of ca. one-year-old lambs or from double the amount if previously split in half.

But how does we translate all of this into string diameters?

The answer can be obtained both by experimental means and by examination of the historical documents.

As regards the former method, we find that the manufacturing of strings today from three whole lamb guts normally leads to unsmoothed string diameters ranging between 0.66 and 0.75 mm.

And what about the historical documentation?

The most significant source from eighteenth-century Italy offering useful evidence for determining diameters is undoubtedly the work of Count Giordano Riccati from Treviso. Riccati was not only an accomplished physicist in the field of acoustic and harmonic theory, but also an accomplished violinist. His book Delle corde, which he began writing in 1740, accurately measures the weight and length of the first three gut strings of his violin: "Colle bilancette dell'oro pesai tre porzioni egualmente lunghe piedi 1 ½ veneziani delle tre corde del violino, che si chiamano il tenore, il canto e il cantino. Tralasciai d'indagare il peso della corda più grave; perchè questa non è come 1'altre di sola minugia, ma suole circondarsi con un sottil filo di rame" (Using gold-weighing scales, I weighed three portions, each 1 ½ Venetian feet long, of the three violin strings, those called the tenore, canto and cantino. I omitted the weight of the lowest string, because unlike the others this is not of gut only, but is usually surrounded with a thin copper wire) (66). Assuming the mean specific weight of gut to be 1.3 gr/cm³, the diameters of the E, A and D are: 0.70, 0.90 and 1.10 mm. The same diameter of the E string is also found on an extant violin chanterelle of silk (silk having approximately the same density as gut). This string, which had never been used, dates from the very end of the eighteenth century and is today preserved in the Académie de Sciences in Paris along with some harp strings (67).

A third possible source of evidence is a "completely intact" violin first string, found in a case with a violin of Nicolas Lambert of 1765 (though this date cannot be verified) and thought to have "never left its case for at least a century" (68). The string, which could well date from the end of the eighteenth century, has a high twist and a diameter of 0.71-0.72 mm. Further evidence consists of some violin E strings belonging to the present author. They are preserved in their original boxes and date from the early years of the twentieth century. They are highly twisted and have diameters ranging from 0.66 to 0.68 mm. This confirms the hypothesis that the manufacturing tradition outlined earlier remained consistent.

Paganini’s strings. Among the evidence in the Palazzo Rosso inventories in Genoa, these finds (more details in Recercare XII, 2000, pp.137-47) consist of a violin bridge, two bows (one broken at various points), a box of rosin made by Vuillaume, and a roll of gut strings in a reasonable state of preservation.

It on this last item that our attention is focused. For it is the first, if not only, instance of gut string samples that can be dated with some certainty: in this case to the early decades of the nineteenth century. The material that we inspected, in April 2001, was preserved in an envelope that had already been opened by its discoverers. It bears the stationer’s stamp of the “Cartoleria Rubartelli Genova”, has a seal of red sealing wax showing the symbol of the City of Genoa and a manuscript inscription in black ink: “Antiche corde del Violino di Nicolò Paganini”.

We measured the string gauges with a micrometer; the strings can be assumed to be two “Ds”, three “As” and two “Es”: it would seem likely that they are segments taken from longer lengths and cut to size for the violin. They are straw-yellow in colour, fragile, slightly wrinkly and intact (i.e. never used).

Below are the diameter ranges found over all the samples:

*this measurement was found on only one segment of string

Other historical data on Italian strings can be derived from certain English violin methods from the late nineteenth century. Huggins, for example, (69) writes the following:

“The measures of a set of Ruffini's strings were found to be:”

Ruffini, the greatest of the late nineteenth-century Neapolitan makers (and not a violinist working in England, as Segerman has suggested) (70), exported his excellent products to cities all over Europe. Strings made in Naples, and particularly by Ruffini, were in great demand in Victorian London: "The best strings in the market to-day are imported from Signor Andrea Ruffini, of Naples, which are sold by all the leading violin-dealers in London (71)". As can be noted, Ruffini's strings — about whose diameters Huggins writes: "these were found to be in about the same relative proportion to each other as the sizes indicated on the gauges sold by several makers (72)" — coincide almost exactly with those calculated by Riccati over a century earlier. This should come as no surprise if we consider that neither the primary resource (the gut of lambs aged eight to nine months) nor manufacturing procedures had undergone significant change since De Lalande’s day, either in Italy or in France. In all likelihood this was equally true for the other Italian cities renowned for their string production, such as Padua and Rome; for all the Italian manufacturers would appear to have descended from the same line of string makers, those of Salle, Musellaro and Bolognano, who later spread over the rest of the country (73).

The strings sold in London by George Hart, Edward Heron-Allen and Bishopp, all probably imported from Italy, had the following diameters (Hart uses the terms "small, medium and thick"), which can be derived from the tensions in pounds given in their tables: (74)

Assuming that the gut used to make the violin E, A and D strings is of exactly the same type and has the same amount of twist, then the number of guts used and the final diameter are, at least in theory, mathematically related (75). Given that the first string of the violin tended to be made of at least three whole lamb-guts (as we saw above) and had a mean gauge of, say, 0.70 mm, then the theoretical diameters of the second and third strings — of respectively five-six and eight-nine guts — are 0.90-1.00 and 1.14-1.21 mm (76). The correspondence with the evidence of Riccati, Savaresse, Ruffini and other French sources is remarkable and seems to confirm our hypothesis that manufacturing procedures were standardized in both Italy and France (though for France, as we saw earlier, this would probably apply as from the beginning of the nineteenth century) (77).

Given that the string length was already sufficiently standardized, the variations in violin working tensions in the eighteenth and nineteenth centuries seem to be mainly the result of variations in pitch standards (78); to a lesser extent they can be attributed to the personal preferences of those who, with the aid of a string-gauge, opted for the larger diameters contained in the boxes (each box of first, second and/or third strings would contain several dozen strings soaked in olive oil, each with the same number of strands) (79). To support the hypothesis that during the early decades of the nineteenth century the tension of violin strings radically increased merely as the result of an increase in string diameters, some scholars use the data from Spohr's string-gauge (80). The marks indicated on the gauge —18, 23, 31 and 25— represent the diameters of the E, A, D and the overspun G (the external diameter, probably). As the system of conversion is not known, They thought fit to refer to a gauge system still used today by certain string makers such as Pirastro: a system that already existed in the nineteenth century and that assigns 20 "grades" to each millimeter. Accordingly, a string marked as 20 P M would have a diameter of 1 mm (20 x 5 = 100 hundredths of a millimeter). In this way the following calibers were calculated: E = 0.90 mm; A = 1.15 mm; D = 1.55 mm and G = 2.22 mm (like equivalent solid gut).

In our opinion, this interesting hypothesis is inconsistent with Spohrs writings, for he not only recommends Italian strings over those made in Germany (which he found too stiff), but also suggests choosing a "light" stringing. And that is not all. If we consider the sizes on his string-gauge illustrated in the text and the position of the markings for measuring the strings, we clearly see that on the basis of the proportion between the total length of the slot and the approximate estimate of its width at the opening — ca. 2 mm — the distance of the E marking shows a width of ca. 0.70 mm rather than the 0.90 mm suggested by Segerman. Therefore the correct ratio is more likely to be a factor of 4, and not a factor of 5, which in any case is based on the subdivision of a modern unit of measurement and not the (unknown) unit of Spohr’ s day (81).

The calibers derived from Spohr's gauge should therefore probably be E = 0.72 mm; A = 0.92 mm; D = 1.24 mm; G = 1.00 mm (corresponding, in our opinion, to the external diameter): results that are evidently in line with the preceding data.