Surgical suture father of medicine, Hippocrates, described suture techniques, as did the later Roman Aulus Cornelius Celsus. The 2nd-century Roman physician Galen described gut sutures. In the 10th century, the catgut suture along with the surgery needle were developed by Abulcasis. The catgut suture was similar to that of strings for violins, guitar, and tennis racquet and it involved harvesting sheep intestines. Joseph Lister endorsed the routine sterilization of all suture threads. He first attempted sterilization with the 1860s "carbolic catgut," and chromic catgut followed two decades later. Sterile catgut was finally achieved in 1906 with iodine treatment. The next great leap
Catgut as withstanding high tension within low alto, tenor, and high-bass ranges. Many acoustic guitarists moved away from gut strings in the early 1900s when the C. F. Martin & Company introduced steel strings, which gave greater volume to the guitar. "The demand for steel came from ensemble players, who couldn't make themselves heard clearly without it." Within a few years the majority of Martin guitars were made with steel strings to accommodate the demand. After World War II, most classical and flamenco guitarists switched from catgut to the new nylon strings for their greater smoothness, durability, and stability of intonation.