Talk:Transatlantic telegraph cable/Archives/2015

48000 km * 0.98 tons/km = 1600 tons ?

"The weight of the new cable was 35.75 long hundredweight (4000 lb) per nautical mile (980 kg/km), or nearly twice the weight of the old. The Haymills site successfully manufactured 30,000 miles (48,000 km) of wire (1,600 tons), made by 250 workers over eleven months."

So how can 48000 km of wire weigh 1600 tons? Is there something wrong or am I missing something here?

• I don't know for sure, but I'm fairly certain that the 48,000 km is referring to the individual wires that make up the cable together. I'm not so sure whether it means the seven copper communication wires (7×73 kg/km, 510 kg/km total), or the eighteen protective high-tensile steel wires; the former would be more relevant, but the latter are specified as being made at Hay Mills/Haymills (I'm assuming the two are equivalent). Also, 48,000 km would only give almost 2,700 km length when eighteen strands are used, ignoring the shortening by the twist; the distance covered is about 3,000 km, but they might have been manufacturing for just one half of the cable. --J. Randall Owens (talk)

• Why the hell does it suddenly, without explanation, and in only one place, use "long hundredweight" as a measurement?????? — Preceding unsigned comment added by 50.197.161.162 (talk) 16:05, 27 May 2015 (UTC)