Musical instruments that start with the letter I include the igil, ipu, Irish uillean, Irish bouzouki, ichigenkin, inci, iya, itotele and istarski mih. The instruments originate from countries ranging from Cuba and Ireland to Croatia, Japan and the Philippines.
Beno Zerr Â· ENSTA Bretagne. Bessel functions are used to solve in 3D the wave equation at a given (harmonic) frequency. The solution is generally a sum of spherical bessels functions that gives the acoustic pressure at a given location of the 3D space.
A serrated mussel shell edge can be used on wood much like a metal rasp. Shells were used to de-bark trees, and to chip out soft charcoal during some stages of canoe making. Mussel shells were used to make the blades of digging tools for agricultural work. A hole would be bashed through the middle of the shell and used to attach the shell to a wooden handle. The shell would be used much like a modern hoe blade (Fig 3). Shells were also used as scraping tools for shaping pottery.