There is another kind of acoustic delay line that was used in late 50's - early 60's that used nickel strips and took advantage of magnetostrictive property of

There is another kind of acoustic delay line that was used in late 50's - early 60's that used nickel strips and took advantage of magnetostrictive property of Ni. I'm calling it acoustic because the memory was in the form of a compression wave propagated from driving magnet to sensing coil, then regenerated. Elliott Brother's 803 series computers used these for the CPU registers.