Rudimentary Geography Question 1

[waterman46]

Originally Posted by StuM

Nope, you still don't get it. You said:
"Each time you go into a new time zone you have to set your clock 1 hour earlier. If you traveled all the way around the world, you would end up setting your clock 24 hours earlier. If you didn't do that, and your clock also had a calendar, you'd find your calender was 24 hours, or one day, later than where it should be."


That is completely wrong.

If you didn't do that, your calendar would be correct.


By not changing your clock at all, its offset from UTC doesn't change.
By turning it back by an hour 24 times, it ends up 24 hours (1 day) earlier than UTC.

You are right, my post was unclear and had an outright error. "If you didn't do that" is completely unclear. If you didn't do what? And "later" should have been "earlier" in my post.


BTW I think the use of bold or underline, red or whatever is very useful to call out the emphasis or differences. It isn't shouting, as some have said. Shouting is the use of all CAPS!!!!!

[StuM]

Originally Posted by waterman46

BTW I think the use of bold or underline, red or whatever is very useful to call out the emphasis or differences. It isn't shouting, as some have said. Shouting is the use of all CAPS!!!!!

Thank you.

[StuM]

Originally Posted by fivecapes

I think you meant Enrique was from Malacca (now Melaka) in Peninsular Malaysia, not Moluccas (Maluku) in East Indonesia.

" few weeks later, another 13 men (12 Europeans and one Moluccan), who were held captive in Cape Verde, returned to Seville, thereby completing the circumnavigation as well. They were the following:
...
"Manuel", a Moluccan without known role"

I can't find any information about whether he was in the fleet when it left Spain or whether he was picked up in Molucca.

If he was in the fleet, then he must have done the first part of his circumnavigation in getting to Spain and the second part on Magellan's voyage, so would have completed his circumnavigation on arrival in Molucca and would have indeed been the first circumnavigator by about 9 months.

Since El Pinguino has apparently asserted the latter, given that he certainly didn't arrive back in Spain until weeks after the first returnees, I presume he can provide evidence that Manuel did join the expedition in Spain, not Molucca.

While not conclusive, it's worth noting this from the Wikipedia article:
"In addition to the returning Europeans, the Victoria had aboard three Moluccans who came aboard at Tidore"
(Tidore is one of the Molucca (Spice) Islands)

[belizesailor]

Originally Posted by tkeithlu

Wow, Stu. That's a beautifully clear explanation. Were you a teacher in another life? If so, your students were lucky to have you.

[emoji106]

[Lodesman]

Originally Posted by StuM

Since El Pinguino has apparently asserted the latter, given that he certainly didn't arrive back in Spain until weeks after the first returnees, I presume he can provide evidence that Manuel did join the expedition in Spain, not Molucca.

While not conclusive, it's worth noting this from the Wikipedia article:
"In addition to the returning Europeans, the Victoria had aboard three Moluccans who came aboard at Tidore"
(Tidore is one of the Molucca (Spice) Islands)

I'm reasonably certain that fivecapes has it right and Pingo in his dotage has gotten it confused.
https://en.wikipedia.org/wiki/Enrique_of_Malacca

The scholarly opinion is that Enrique was dropped at Cebu, but it is unknown if he made it on his own back to Malacca, some 2500 miles away. He had the better part of a year to do so, but I doubt it would have been an easy trip in 1521. There is certainty about the return of Elcano et al, so I think the spoils go to them.

[Benz]

Originally Posted by El Pinguino

That carried on until well into the 1930s.... and only died out after people( old phart captains?) became used to using radio time signals to correct their chronometers.

So yes .. they set their days from local apparent noon... which is why my 1960ish Nories has has speed / days run tables based on 22h to 26h days.....

drifting even further, I've long thought that a set of tables containing a "best fit" sine curve equation would be a really handy way of finding LAN without having to shoot the sun at precisely noon, or average a bunch of shots before and after. Three shots; altitude and GMT as arguments, and voila! Time of LAN. I just need a math geek to help with the equation bit.

[El Pinguino]

Originally Posted by Lodesman

I'm reasonably certain that fivecapes has it right and Pingo in his dotage has gotten it confused.
https://en.wikipedia.org/wiki/Enrique_of_Malacca

The scholarly opinion is that Enrique was dropped at Cebu, but it is unknown if he made it on his own back to Malacca, some 2500 miles away. He had the better part of a year to do so, but I doubt it would have been an easy trip in 1521. There is certainty about the return of Elcano et al, so I think the spoils go to them.

I recall reading it in an article about the voyage published in 'The Mariner's Mirror' - a publication you may or may not be familiar with - some 15 or 20 years ago... it will be in the shed somewhere.... but no I don't feel inclined to provide proof.... and yes..in my dotage I may indeed be confusing my Moluccas with my Malaccas...

[El Pinguino]

Originally Posted by Benz

drifting even further, I've long thought that a set of tables containing a "best fit" sine curve equation would be a really handy way of finding LAN without having to shoot the sun at precisely noon, or average a bunch of shots before and after. Three shots; altitude and GMT as arguments, and voila! Time of LAN. I just need a math geek to help with the equation bit.

Nories do have the Ex-Meridian Tables... 17 pages of them ... to correct the altitude from a sight taken just before or after MerPas. I must admit I have never felt the need to use them...
Accurate time of mer pass... two equal altitudes will do that... note time diff... divide by two... add result to time of first sight.. job done.

[Benz]

Originally Posted by El Pinguino

Nories do have the Ex-Meridian Tables... 17 pages of them ... to correct the altitude from a sight taken just before or after MerPas. I must admit I have never felt the need to use them...
Accurate time of mer pass... two equal altitudes will do that... note time diff... divide by two... add result to time of first sight.. job done.

With my proposed method (if it works), you won't need two equal altitudes. With the midmorning and midafternoon LOP shots, and one whenever in between, you could find time of LAN. Seems terribly convenient to me.

[SeanPatrick]

Originally Posted by Benz

With my proposed method (if it works), you won't need two equal altitudes. With the midmorning and midafternoon LOP shots, and one whenever in between, you could find time of LAN. Seems terribly convenient to me.

Have you searched the archives of NavList* or tried posting there? I'm sure someone there could help.


*Try searching for the phrase "equal altitudes" and sort the results by date.

[Benz]

Originally Posted by SeanPatrick

Have you searched the archives of NavList* or tried posting there? I'm sure someone there could help.


*Try searching for the phrase "equal altitudes" and sort the results by date.

A quick search revealed nothing. Perhaps it would simply be one tool too many in a box that's already suffering a regrettable neglect.

[SeanPatrick]

Originally Posted by Benz

A quick search revealed nothing. Perhaps it would simply be one tool too many in a box that's already suffering a regrettable neglect.

Perhaps coincidentally, there are some new posts on this very subject over at NavList.

[Benz]

Originally Posted by SeanPatrick

Perhaps coincidentally, there are some new posts on this very subject over at NavList.

Nice. I'm getting at something like this, only with a very simple set of tables. Thanks for the heads' up, though.