Sunday, September 16, 2018
Wheatstone all the way down
As I learn about the astonishingly complex and creative computing system called Railroads, one DOMINANT concept appears over and over.
From the start, railroad circuitry and mechanisms were DIFFERENTIAL. Two-sided, like nervous systems. The hugely complex staff system was diff all the way.
On the electrical side, this was a British tendency, starting from Mr Diff himself, Wheatstone. Later British electronics carried on the principle of balance. A balance doesn't have an absolute zero, it only has DELTAS between two or more inputs. British culture and politics are also diffish. See Shadow Cabinet.
American electronics has tended more toward on/off, 1/0, again starting from Mr On-Off himself, Morse. An American system does have an absolute zero. Our politics and culture continue the On-Off tradition. See Impeachment.
Obviously both tendencies are needed in various situations, but railroads are a British invention and always retained the British preference for diffs and deltas.
The simplest mechanical expression of a diff is the switch.
Always this way vs that way, SPDT. Not this way vs no way, SPST. There are always two destinations, even when one of them is a short siding for a loading dock. You can't send REAL PHYSICAL OBJECTS into nowhere. You can send bits and bytes into nowhere. An economy devoted to bits and bytes, or a "store of value" consisting of bits and bytes, can be obliterated in an instant.
Switches have been part of the system for 170 years. There are an uncounted number of switches... probably millions? ... in the world. Each one moves back and forth by just a few inches, turning a vast load of REAL VALUE toward one path or the other, bearing millions of tons of weight, lasting many decades.
That's a SUCCESSFUL TECHNOLOGY. 
Always this way vs that way, SPDT. Not this way vs no way, SPST. There are always two destinations, even when one of them is a short siding for a loading dock. You can't send REAL PHYSICAL OBJECTS into nowhere. You can send bits and bytes into nowhere. An economy devoted to bits and bytes, or a "store of value" consisting of bits and bytes, can be obliterated in an instant.
Switches have been part of the system for 170 years. There are an uncounted number of switches... probably millions? ... in the world. Each one moves back and forth by just a few inches, turning a vast load of REAL VALUE toward one path or the other, bearing millions of tons of weight, lasting many decades.
That's a SUCCESSFUL TECHNOLOGY. Labels: Morsenet of Things, Natural law = Sharia law, Natural law = Soviet law, Patient things
¶ 2:34 AM
