Two excellent new books on the history of technology

1. David Arnold, Everyday Technology: Machines and the Making of India’s Modernity.  The typewriter and the bicycle revolutionized India early in the twentieth century

2. Ernest Freeberg, The Age of Edison: Electric Light and the Invention of Modern America.  Two of the takeaways from this book are a) the United States had a more statist approach to electricity infrastructure than did most of Europe, and to its advantage, and b) we didn’t let lots of people accidentally being electrocuted stop progress, again probably to our advantage.


I'd like to see a book about Almon Strowger, the inventor of the dial telephone. Most of his career was as an undertaker, and he suspected that a competitor's wife, who was a telephone operator, was sending business toward her husband's funeral parlor. In the ultimate revenge of the nerds, Strowger came up with an invention to get rid of telephone operators everywhere.

I'm willing to believe TC's take-aways from in the broad sweep of things, I'd say the 110V standard is an exception. It is (b) a disadvantageous idea design to prevent electrocution.

It also (a) smells like the work of politicians, though I can't claim that outright - my knowledge is limited. Still it seems like some government reaction to Edison's scare campaign about high voltages.

Edison's scare campaign was against AC, not high voltage. DC is much less of an electrocution hazard than AC, and 60 Hz is a particularly dangerous frequency. However, DC would also have been a greater fire hazard, because of the increased arcing at power switch contact points. 400 Hz (the standard frequency used in aircraft) would have been a safer frequency for AC because it is much less likely to provoke cardiac fibrillation, and it would have allowed for smaller and cheaper transformers. 60 Hz was a poor choice.

How would you step DC up and down? Especially 100 years ago.

That's why AC couldn't have been adopted in the old days -- transformers only work on AC. Edison's system required local powerplants everywhere. 400 Hz AC would have been much safer against electrocution than 60 Hz AC, safer against fire than DC, and the equipment would have been cheaper.

There was a way to convert between DC voltages using motor-generator sets. They have reasonable efficiency (not as high as transformers, of course), but they're expensive and they wear out.

Wouldn't transmission losses be huge for 400 Hz AC? I think there's a good reason it has only seen use in small-size networks like ships and aircraft.

You can compensate for the decrease in skin depth by the design of the transmission lines. If you converted a 60 Hz line to 400 Hz, yes the losses would go way up.

Even for a new line, a tailor made design suitable for long distance 400 Hz AC, would have way higher capital costs I suspect, if you keep losses at the same level as a conventional 60 Hz AC line.

It is (b) a disadvantageous idea design to prevent electrocution.

Yes, but it's only trivially disadvantageous. What percentage cost is associated with the difference in 120V (the actual nominal standard, YMMV), vs the EU 230V standard? I'm guessing less than a 1% difference in efficiencies, effectively probably much less than 1%.

The I2R loss would be 4 times as much. Typically T&D losses are 7%. Not sure how much of this is last mile conductor loss.

But does seem like the difference ought to be more than 1%.

"... history of technology"

Hope to someday see a good book-level treatment of Doug Engelbart and other computing visionaries of his time. RIP.

I smile whenever Tyler uses words like "statist" and "progress" in an approving way.

"we didn’t let lots of people accidentally being electrocuted stop progress"

Right, we thankfully used statist policies to mitigate the risk of electrocution.

How many regulations written by how many NGOs does the state require you to comply with so electricity does not kill and destroy?

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