Strings (tennis) be more durable than many other types of strings due to its outstanding tension retention. This may help to offset the high initial cost. The use of a dense string pattern also generally improves the longevity of natural gut. Natural gut is produced by drying fibers extracted from a part of the cow intestine called the serous membrane, or serosa, which contains collagen designed to withstand the stretching and contraction of the intestine. It is this elasticity that makes the fibers useful for tennis string. Sheep intestines have also been used for racquet strings in the past. The first natural
Geophone (musical instrument) performance in New York City). Messiaen's wife, Yvonne Loriod, commented that when she and the composer first collected the new instrument from the maker in her car it made a "splendid crescendo" whenever they went round a corner. Messiaen also included the instrument in his only opera, "Saint François d'Assise", which was first performed in Paris 1983. Other works that use the geophone include "Asyla" by Thomas Adès, "…towards a Pure Land" by Jonathan Harvey, and the operas "The Sacrifice" by James MacMillan and "Dark Sisters" by Nico Muhly. Geophone (musical instrument) The geophone is a percussion instrument, invented by