The Alp horns built and sold by the late Joseph Littletown of Hammondsport, NY are analyzed. His dimensions of bore as a function of position are used in the solution of the Webster equation for impedance solved numerically earlier for the flügelhorn and the trombone. In addition, the steady flow through the instrument is calculated by Laplace equation. The musical notation for the frequencies of the impedance peaks found by the solutions to the Webster equation are given below. Here the subscripts refer to the harmonic number. The fundamental, rarely used, is 12 cents sharp from Eb at 51.9 Hertz. The intonation errors for C1, C2, G3, C4, E5, G6, B7b, C8, D9, E10, F11, G12, A13, B14b B15, C16, C17# and D18 are 269, 30, 63, -39, -41 ,-25, -13, -7, -11, -1, 2, 11, 11, 15, 15, 20, 24 and 28 cents.