The Peralta Stones

[Blindbowman]

here i will help you once ... you see this old set of dividers .. thats the type of tool that made the drawings on the stones ,, ya portuguese captains had them .. ........

 

[mrs.oroblanco]

BB,

I've seen a lot of dividers in my time, but, I will admit, I have never seen a pair like you are showing, nor have any clue as to how that would be used for stone. ?

Beth

 

[Real de Tayopa Tropical Tramp]

HI Beth, those are probably old shipboard dividers, They were made sturdier by using that curved section for extra support. On an old sailing ship, pitching and rolling, it would be all too easy to spring a standard type.

Don Jose de La Mancha

 

[Blindbowman]

HI Beth, those are probably old shipboard dividers, They were made sturdier by using that curved section for extra support. On an old sailing ship, pitching and rolling, it would be all too easy to spring a standard type.

Don Jose de La Mancha

very true my friend ...i have uses this type before ,and they are very very hard and can be re sharpend dozen and dozen of times ..they are also razor needel sharp ...and can be sharpend with a common wet stone ..

 

[shadow hunter]

what leads you to the conclusion that those are what the tool of choice was when making this map? let's hear some thoughts behind this?

 

[EE THr]

I don't think that being sharp had a lot to do with the quality or accuracy of dividers back then, because who would want to poke holes in their maps?

Even "modern" use of navagation dividers include the use of glass or plexi over the map, and a grease pencil to mark your sightings and course with, so they can be erased, and to protect the map.

 

[mrs.oroblanco]

Ok, I'm officially confused.

If you sharpen them with a stone, how are they used to work on stone maps? I can understand how to use things (from dividers to compasses, etc for paper maps) but, I thought we were talking about stone. Are you talking about "scratching" the surface before it is carved?

Beth

 

[shadow hunter]

Good point EE THr and Beth....

plus the odds of the person who made the map having that particular kind of instrument is highly unlikely. I am not saying he/she did not have something similar, but the high quality, sea mapping kind is kinda a far fetch. also, anyone that mad maps out in the sea rely heavily on the stars and the time of year, these maps don't really give that kind of indication. I think BB it was a valient attempt, but i don't think anyone is buying into that theory. I don't have a theory on how they were made, but you know the old saying, “Wise men speak because they have something to say; Fools speak because they have to say something.”

 

[Cubfan64]

“Wise men speak because they have something to say; Fools speak because they have to say something.”

That should be locked at the top of every forum post

 

[mrs.oroblanco]

“Wise men speak because they have something to say; Fools speak because they have to say something.”

I love that statement - kewl.

B

 

[Blindbowman]

what leads you to the conclusion that those are what the tool of choice was when making this map? let's hear some thoughts behind this?

first off i dont think they are the tool that made the stone maps, i know they are .. there is a reason why i posted that type .. i did not just guess ..

 

[Blindbowman]

I don't think that being sharp had a lot to do with the quality or accuracy of dividers back then, because who would want to poke holes in their maps?

Even "modern" use of navagation dividers include the use of glass or plexi over the map, and a grease pencil to mark your sightings and course with, so they can be erased, and to protect the map.

..you sir are so wrong ...thats out right not true .. the new dividers are still used on the surface of the charts . the charts are plastic coded surface .. but that is made right on to the chart it self .in fact very much like the Beartooth...read the front of the map .. it says "Waterproof Tear Resistant plastic". i think you are talking about CIC tracking plexaglass boards .. use to do combat tracking ..to much TV i guess..lol


http://www.columbusnavigation.com/dr.shtml


"pricking the chart with a pin to mark the new position" this so call expert is also confused a pin was not used .. the divider pionts were and still are .. the modern type of dividers have a much more pin prick effect .. but the marks made reflect hunders of years of navigation skills past down in training and sea fairing guides and training books..

 

[Blindbowman]

Good point EE THr and Beth....

plus the odds of the person who made the map having that particular kind of instrument is highly unlikely. I am not saying he/she did not have something similar, but the high quality, sea mapping kind is kinda a far fetch. also, anyone that mad maps out in the sea rely heavily on the stars and the time of year, these maps don't really give that kind of indication. I think BB it was a valient attempt, but i don't think anyone is buying into that theory. I don't have a theory on how they were made, but you know the old saying, “Wise men speak because they have something to say; Fools speak because they have to say something.”

do some research before you reply ,, you are wrong again "anyone that mad maps out in the sea rely heavily on the stars and the time of year"

where did you get this idea .. its out right wrong .

 

[shadow hunter]

Good point EE THr and Beth....

plus the odds of the person who made the map having that particular kind of instrument is highly unlikely. I am not saying he/she did not have something similar, but the high quality, sea mapping kind is kinda a far fetch. also, anyone that mad maps out in the sea rely heavily on the stars and the time of year, these maps don't really give that kind of indication. I think BB it was a valient attempt, but i don't think anyone is buying into that theory. I don't have a theory on how they were made, but you know the old saying, “Wise men speak because they have something to say; Fools speak because they have to say something.”

do some research before you reply ,, you are wrong again "anyone that mad maps out in the sea rely heavily on the stars and the time of year"

where did you get this idea .. its out right wrong .

please enlighten me sir. because from what i have been taught is maps were made at sea by using the stars. Sailors measured the position of the stars above the horizon using a sextant, from a table of known postions of the stars. they also had to know what time of year and what time of day it was, this was taken from a known point at Greenwich in England (Greenwich Mean Time GMT). Every place on earth takes its time from being plus or minus so many hours from GMT. If you could please tell show me the other methods used i would be more then happy to learn something new. well, let me clarify, I would be happy to learn something new if it had some truth behind it then a wild eyed theory.

 

[Blindbowman]

Good point EE THr and Beth....

plus the odds of the person who made the map having that particular kind of instrument is highly unlikely. I am not saying he/she did not have something similar, but the high quality, sea mapping kind is kinda a far fetch. also, anyone that mad maps out in the sea rely heavily on the stars and the time of year, these maps don't really give that kind of indication. I think BB it was a valient attempt, but i don't think anyone is buying into that theory. I don't have a theory on how they were made, but you know the old saying, “Wise men speak because they have something to say; Fools speak because they have to say something.”

do some research before you reply ,, you are wrong again "anyone that mad maps out in the sea rely heavily on the stars and the time of year"

where did you get this idea .. its out right wrong .

please enlighten me sir. because from what i have been taught is maps were made at sea by using the stars. Sailors measured the position of the stars above the horizon using a sextant, from a table of known postions of the stars. they also had to know what time of year and what time of day it was, this was taken from a known point at Greenwich in England (Greenwich Mean Time GMT). Every place on earth takes its time from being plus or minus so many hours from GMT. If you could please tell show me the other methods used i would be more then happy to learn something new. well, let me clarify, I would be happy to learn something new if it had some truth behind it then a wild eyed theory.

sorry to have been so forward .. i have had a injury last week and have spent the last 4 days with my back out ,, wich dose not feel very good ..

no sorry you were wrong .. most people believe the same thing .. but its not true .. i have shot well over 80,000 star & sun azimuth lines useing a sextant ,, this type of navigation dose not become common untill the perfection of the magnetic compass after the early 1600,, before this stars were more a random guessing game ..we learn most of our modern basics from the portuguese ,, two real good exsamples ,, one link i posted , here is another that will help you under stand the basics


Columbus and Dead Reckoning (DR) navigation
http://www.columbusnavigation.com/dr.shtml

Dead reckoning and magnetic declination: unveiling the mystery of
www.e-perimetron.org/Vol_3_4/Gaspar.pdf

 

[Real de Tayopa Tropical Tramp]

Good morning: I have to partially side with BB on this. Maps were made on shore with the accumulated data from the pilots of that time. The first crude attempts to measure Celestial bodies 'prob'. came in the 1600's using astrolabes. The later refinement of using a sextant required an accurate time piece as suggested by Shadow. The usual needed position correction, came with the normal noon day sun shot, or Moon shot which when used with reference to the time piece adjusted to Greenwich, gave a fairly accurate location . The accumulated data from many pilots logs was then transferred to the charts.

Geeze, it has been so long since I did any celestial navigation that I am a bit rusty on my historical and actual memories, so don't shoot me if I am a bit off.

Don Jose de La Mancha

 

[shadow hunter]

BB

interesting site, like they say.....you learn something new everyday, and that was mine today. I do see where you are coming from on how they navigated then, and i can see your point. I still don't buy into the fact that you think the stones were carved with such an instrument, but i can see how you may suggest that as a theory. i do have a question though, let's say that they did use deviders to carve the map, and as they dulled they had to resharpen them. would it be safe to say that the carvings would indicate that by showing some places that are more dull and rounded in the stone, opposed to a newly sharpened tool that would leave a deeper sharper cut in the stone. so presumably the stones carvings would have differnt styles of cuts on them depending on the sharpness of the tool used?

shadow hunter

 

[Blindbowman]

Good morning: I have to partially side with BB on this. Maps were made on shore with the accumulated data from the pilots of that time. The first crude attempts to measure Celestial bodies 'prob'. came in the 1600's using astrolabes. The later refinement of using a sextant required an accurate time piece as suggested by Shadow. The usual needed position correction, came with the normal noon day sun shot, or Moon shot which when used with reference to the time piece adjusted to Greenwich, gave a fairly accurate location . The accumulated data from many pilots logs was then transferred to the charts.

Geeze, it has been so long since I did any celestial navigation that I am a bit rusty on my historical and actual memories, so don't shoot me if I am a bit off.

Don Jose de La Mancha

very true .. the best time to shot a sun line with a sextant is between 10:00 -02:00 why because the elevation is greater and thus leaves less room for vairation in modern sextant the azimuth reading is corrected twice . ones for daylight saveings time and the secound is a hymisphere correction , the reason those times are better is think of rough sea waves .. no one said the job was easy ...the astrolabes are not very fun to use , but they do the same thing messure azimuth ..these readings are between 0.00 and 90 degrees,, a variration is less then 100th of a degree

 

[Blindbowman]

BB

interesting site, like they say.....you learn something new everyday, and that was mine today. I do see where you are coming from on how they navigated then, and i can see your point. I still don't buy into the fact that you think the stones were carved with such an instrument, but i can see how you may suggest that as a theory. i do have a question though, let's say that they did use dividers to carve the map, and as they dulled they had to resharpen them. would it be safe to say that the carvings would indicate that by showing some places that are more dull and rounded in the stone, opposed to a newly sharpened tool that would leave a deeper sharper cut in the stone. so presumably the stones carvings would have different styles of cuts on them depending on the sharpness of the tool used?

shadow hunter

the answer to your question is no .. in this case the dividers are so sharp the avg eye sight could not defind the difference but the trained skills of the navigator would know the tool was becoming dull and sharppen it way before the avg person would see it taking place ..

for the most part there would be very little if any seeable sign of the tools dulling .. but .. this said .. look who noticed it .. another navigator ...i stated the stones were not finished .. and if you look close some lines are nothing more then scratches why most are in full detail .. note .. the lesser are not as deep and are not as smooth on the edges .. why because it would take many traces of the same line to ware them down and those that are deeper are for most part wider as well and the same condition is not only in the lines of the drawing but also the holes them self's ..

we could test this by a machinist's dial indicator by measuring the depth of the holes vs the wide .. it will confirming one tool made all the holes and then we can use that data and compair the variation of the hole to the variation of the lines ,, they should share a common variation between them if i am correct .. being both a machinist and a navigator i believe i am correct

plus i am saying only what i need to at this point .. i know a lot more about this person and the stones then i am willing to share at this point in time ..

 

[Real de Tayopa Tropical Tramp]

BB, the Astrolabe was used to find the probable latitude, nothing more. They would sail North or South to the approx Latitude, then sail east or West to the desired landfall. Not very accurate, but it fullfilled the requirements of the day.

Prob on par with your work, why US ships ended up on rocks or shoals. snicker.


Don Jose de La Mancha