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.
Bessel's functions are often used in acoustics for describing circular membranes behaviour (exploited by most of the musical instruments). They are the solutions of the wave equations using polar coordinates. Set the properties of the membrane Bessel's functions describe the vibrational modes of the membrane.
You shall make tassels [tzit-tzitot] on the four corners [kanafim=wings] of the clothing with which you cover [kacah] yourself Deu 22:12. This garment is used at all major Jewish occasions: circumcisions, bar mitzvahs, holidays, weddings and burials. It originally was a poncho-type wrap that extended below the knees. Later, the talit-katan (tah-leet kah-tahn), a shorter poncho-type garment, was worn.