[Leica] Babbage Difference Engine

[lrzeitlin at aol.com (lrzeitlin at aol.com)]

 Herbert,From Wikipedia?s article on magnetic core memories:
"Two key inventions led to the development of magnetic core memory in 1951. 
The first, An Wang's, was the write-after-read cycle, which solved the 
problem of how to use a storage medium in which the act of reading erased 
the data read enabling the construction of a serial, one-dimensional?shift 
register?of o(50) bits, using two cores to store a bit. A Wang core shift 
register is in the Revolution exhibit at the?Computer History Museum. The 
second,?Jay Forrester's, was the coincident-current system, which enabled a 
small number of wires to control a large number of cores enabling 3D memory 
arrays of several million bits e.g.?8K x 8K x 64 bits.? ?So I guess we are 
both right.


Now back to the Leica S. A toy for the very rich.


Larry Z