One of the things I want to learn more about is string tension in the 19th century, in particular in connection to Piatti and the Milanese cello school. A good starting point seems to be the cello method by Guglielmo Guarenghi (1877), a friend of Piatti who studied with the same teacher (Merighi) in Milan. Quarenghi writes that the tension of each cello string must be 13 Kg. At A=440, this would correspond to an A string of 1.18 MM and a D string of 1.76 (uncovered gut). Quarenghi doesn’t specify the pitch, but in another chapter he writes that the lowest note of the cello has a frequency of 130,5 Hz, which corresponds more or less to a 440 tuning.
Piatti was working in England during most of his career. It is said that English cellists of the Lindley-school were using very thick strings. I have yet to find a source on how thick exactly. Also, I intend to find out whether or not Piatti converted to the “English system” at some point in his career. That is, if there still was an English system when he arrived… In a review from 1846 of a concert in London by Piatti, the reviewer complains (about the piece by Romberg that Piatti played, not about his performance, which he loved): “It is the fault, we think, of almost every solo player on the violoncello, to throw almost entirely aside the full, deep tones which belong to its natural scale, and to scramble incessantly towards the bridge in search of tones which belong to the compass of the violin, though inferior in quality; producing an effect like the singing of some Italian tenors, who insist on warbling incessantly in falsetto. To facilitate this, too, these violoncellists string their instruments with mere threads, from which the full tone of the instrument cannot be drawn.”