Help with (fictional) celestial navigation

[Stu Jackson]

Originally Posted by skipmac

Surely at least some of these derive from some common use of the word dead.

Of course. That's 'cuz all those old sailors are, by now, uhm, dead.

[skipmac]

Originally Posted by Stu Jackson

Of course. That's 'cuz all those old sailors are, by now, uhm, dead.

I was thinking more like all those old sailors getting grog all the time they were dead drunk.

[El Pinguino]

Its all a bit academic really as real sailors just say and write DR.
A bit like radio detection and ranging.

[Wotname]

Originally Posted by El Pinguino

Its all a bit academic really as real sailors just say and write DR.
A bit like radio detection and ranging.

Actually that's pertinent for me right now

A week or so back, I was forced (socially) to listen to someone banging on about the Philadelphia Project or something similar and he was sporting a lot of hogwash about radar beams and such. Finally I could stand it no more and causally asked him what radar was short for. He just looked at me like I was very blonde and replied "Don't be silly, it doesn't stand for anything, it's a complete word by itself".

I didn't bother to reply, just got another beer and went outside to stare at the stars.

[skipmac]

Originally Posted by Wotname

Actually that's pertinent for me right now

A week or so back, I was forced (socially) to listen to someone banging on about the Philadelphia Project or something similar and he was sporting a lot of hogwash about radar beams and such. Finally I could stand it no more and causally asked him what radar was short for. He just looked at me like I was very blonde and replied "Don't be silly, it doesn't stand for anything, it's a complete word by itself".

I didn't bother to reply, just got another beer and went outside to stare at the stars.

My hat is off to you sir. You demonstrated much greater restraint than I could have in the situation. I doubt I would have been able to resist explaining the acronym to a blowhard.

[NevisDog]

Originally Posted by skipmac

I can think of a number of sailing terms that also use dead..... Surely at least some of these derive from some common use of the word dead.

That's dead right, and dead clever too if I may say so! The common usage of 'dead' from my childhood years was to emphasize the accuracy of a statement. 'Deduced reckoning' would surely be a redundancy, equivalent to saying deduced deduction, or reckoned reckoning - not something a simple sailor lad would dream up.

My 1910 copy of 'Wrinkles' quotes Lord Kelvin's lecture on dead reckoning, beginning, "When no landmarks can be seen, when the water is too deep for soundings, if the sky is cloudy... the navigator... has no other way of knowing where he is than the dead reckoning..."

He goes on to quote "the mariner's creed": Lead, Log, Latitude and Look-out! I can recall entering harbor at low water, swinging the lead every few yards to ensure we didn't touch bottom, and in fog, tossing a scrap (log) of wood over the bow to estimate speed. Echo sounders and Walker logs were around then, but for some of us electronics, and even engines, were luxuries we couldn't afford, so accurate DR was critical.

[Stu Jackson]

Originally Posted by skipmac

My hat is off to you sir. You demonstrated much greater restraint than I could have in the situation. I doubt I would have been able to resist explaining the acronym to a blowhard.

Blowhards usually don't even understand what an acronym is.

[skipmac]

Originally Posted by NevisDog

He goes on to quote "the mariner's creed": Lead, Log, Latitude and Look-out! I can recall entering harbor at low water, swinging the lead every few yards to ensure we didn't touch bottom, and in fog, tossing a scrap (log) of wood over the bow to estimate speed. Echo sounders and Walker logs were around then, but for some of us electronics, and even engines, were luxuries we couldn't afford, so accurate DR was critical.

The use of the lead line and soundings was in the past a very useful tool. There is a bit in Two Years Before the Mast when they are making landfall back in the US after a non-stop trip around the Horn. Not only the depth but the bottom characteristics were well known to the navigators. So when they threw the lead the pocket in the bottom was filled with tallow to bring up a sample from the bottom.

"The soundings on the American coast are so regular that a navigator knows as well where he has made land by the soundings, as he would by seeing the land. Black mud is the soundings of Block Island. As you go toward Nantucket, it changes to a dark sand; then, sand and white shells; and on George's Banks, white sand; and so on."

I made a trip from RI to FL a few years back without a depth sounder (not by choice) and did just fine with an improvised lead line, a big SS nut on a piece of string.