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Comment: Re:Library Science was and is a true profession (Score 2) 93

by Deadstick (#48653379) Attached to: Librarians: The Google Before Google

Sanitation was the first engineering challenge and it has yet to go away. You can pretty well locate a population on the technology totem pole by observing how it takes a shit. I suspect Rome in the second century, thanks to its spending on engineering, smelled better than London in the 18th.

Comment: Re:Like many inventions ... (Score 1) 247

by Deadstick (#48652965) Attached to: The Magic of Pallets

There was something like that in 19th-century fire departments. Their wagon had a storage tank and two pump/hose assemblies: one to suck up water from the nearest river, and one to spray it. The outflow pumpers tried to empty the tank, and the inflow pumpers tried to overflow it, with bragging rights hanging in the balance.

Comment: Re:This is where the ton for AC capacity comes fro (Score 1) 83

by Deadstick (#48652647) Attached to: How a Massachusetts Man Invented the Global Ice Market

More formally, the rate of heat absorption of ice melting at a rate of one short (i.e., not metric) ton per day. It's about 12,000 Btu's per hour or 3517 watts.

Note that this does not include any heat required to bring colder ice up to the melting point, or any heat added after the melting takes place. The power required to drive an air conditioner equals the number of tons, times 3517 watts, divided by the coefficient of performance of the unit (which is in the neighborhood of 3 for most AC installations). So a one-ton unit with COP 3 will draw a bit over a kilowatt while it's cooling; what you see on your electric bill will be that, times the fraction of the time that the thermostat commands cooling on.

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