Congratulations, happenby, for giving an intelligent reply.

Quote from: happenby

Perhaps Neil is talking about an astrolabe. Used from about the year 250 until the 16th century.

Astrolabe
From Wikipedia, the free encyclopedia

"An astrolabe (Greek: ?????????? astrolabos, "star-taker")[1] is an elaborate inclinometer, historically used by astronomers and navigators, to measure the inclined position in the sky of a celestial body, day or night. It can thus be used to identify stars or planets, to determine local latitude given local time and vice versa, to survey, or to triangulate. It was used in classical antiquity, the Islamic Golden Age,[2] the European Middle Ages and the Renaissance for all these purposes.
While the astrolabe is effective for determining latitude on land or calm seas, it is less reliable on the heaving deck of a ship in rough seas. The mariner's astrolabe was developed to solve that problem."

Astrolabes were highly accurate and were eventually joined with precision time pieces.

Information on the mariners astrolabe for rough seas is found here.
https://en.wikipedia.org/wiki/Mariner%27s_astrolabe

Wiki continues

"At first mechanical astronomical clocks were influenced by the astrolabe; in many ways they could be seen as clockwork astrolabes designed to produce a continual display of the current position of the sun, stars, and planets. For example, Richard of Wallingford's clock (c. 1330) consisted essentially of a star map rotating behind a fixed rete, similar to that of an astrolabe.[27]
Many astronomical clocks, such as the famous clock at Prague, use an astrolabe-style display, adopting a stereographic projection (see below) of the ecliptic plane."

The astrolabe was used to do the job of determining latitude but they were very challenging to use at sea, as you have indicated, making them accordingly inaccurate. This principle was further developed by an invention that occurred in the 18th century that enables its use even in adverse conditions with greater accuracy, and was improved over many decades, even centuries, to the point where now very effective and precise versions are made even today, to serve as backup tools when GPS systems fail to deliver. I am going to post one video that demonstrates in great detail how to use a particular version made in Germany, for example.

I'll give you another chance to guess the name of the device to which I refer, before I post some very instructive videos that cover how they are used by modern navigators at sea.

Quote from: Truth is Eternal

Quote from: Neil Obstat

Quote from: FlatEarthInquisitor

Quote from: Neil Obstat

Quote from: FlatEarthInquisitor

Now if you would like to ask me a question, with respect, I am more than happy to try to answer.

Okay, I'll ask you directly, if that's important to you:

What is the name of the instrument that mariners have been using for the past 6 centuries

Actually it has been more like the past 4 centuries, but the principle it's based on has been used much longer than that.

Quote

Quote

to determine their angular distance in the northern hemisphere from the equator?

No it is not important to me whether you ask me or not. The point, which you still don't get, is you need to change your attitude. You're clearly a very unhappy person.

The purpose of forums is not to compete to see who can make the nastiest remark to other people. It is to arrive at the truth.

I know what instrument you are talking about, but why do you want to know? Is it pivotal to accepting the flat earth for you?

Your incessant penchant to comment on your opinion of the happiness of your opponent is telling.

If you know what the instrument is, perhaps you can explain how it works.
What I would like to know is how you can explain its function, in your dream world.

That is, explain how it works when presuming there is no curved surface on the earth.
For example, how do you measure the angular distance from the equator if there is no such angle like on a "flat earth"?

The ball's in your court.

The horizon always appears perfectly flat 360 degrees around the observer regardless of altitude. All amateur balloon, rocket, plane and drone footage show a completely flat horizon over 20+ miles high. Only NASA and other government “space agencies” show curvature in their fake CGI photos/videos.

FAIL.

True to form, you have again ignored my question and have attempted to change the subject.

Your answer about the horizon being flat, amateur balloon, rocket, NASA, CGI, etc., does not answer the question: What device has been used for the past few centuries to determine latitude from the rolling deck of a ship at sea (which is what a sailor has to deal with) and how does it work in your flat-earth model?

In any event, thank you for not continuing to whine about how you think I must feel, because that makes you appear feminine, even while you complain that I reply to women not to men. If you want me to reply to you then you should try acting like a real man.

E.g., try acting like a man by answering the question like a man, instead of trying to change the subject.

There were several instruments with different advantages, including the octant and quadrant, but the most effective and least limited is the sextant.

It remains that no curvature of the earth has ever been demonstrated. Further, things like lighthouses, gyros, sundials, bubble levels, compasses, astrolabes and sextants were developed by people with the horizontal plane in mind. For good reason. Earth is a plane. While extrapolation and clever doublespeak goes a long way to show how these might operate on a sphere using low down lies and high brow 'math', in fact,  by their very nature, these devices were designed for measurments that are TRUE.

Stop being needlessly pedantic and condescending, and make an argument. I agree with you and I still find you almost as infuriating as the deluded people in this thread.

Here is a well-known person explaining how to plot the position of your boat at sea, using a sextant together with The Air Almanac, which was published twice each year when the video was made (1984).

Especially noteworthy is minute 5:15 when Mr. Buckley says for the purposes of celestial navigation the earth is presumed motionless with the sun continually moving around it. His model shown at that point speaks for itself. It would make no sense whatsoever if the earth were "flat."

[youtube]https://www.youtube.com/embed/Xz0VazejX1Q[/youtube]

Why do those who espouse a flat earth claim that water cannot cling to a "ball" earth because gravity would not allow for it, and then also say that gravity is a myth?

Why do those who espouse a flat earth claim that water cannot cling to a "ball" earth because gravity would not allow for it, and then also say that gravity is a myth?

If you fill a balloon with helium, a substance lighter than the nitrogen, oxygen and other elements which compose the air around it, the balloon will immediately fly upwards. If you fill a balloon with hydrogen, a substance even lighter than helium, the balloon will fly upwards even faster.

If you blow a dandelion seed out of your hands, a substance just barely heavier than the air, it will float away and slowly but eventually fall to the ground. And if you drop an anvil from your hands, something much heavier than the air, it will quickly and directly fall straight to the ground.

Now, this has absolutely nothing to do with “gravity.” The fact that light things rise up and heavy things fall down is simply a natural property of weight. That is very different from “gravity.” Gravity is a hypothetical magnetic-like force possessed by large masses which Isaac Newton needed to help explain the heliocentric theory of the universe.

Now, even if gravity did exist, why would it cause both planets to orbit the Sun and people to stick to the Earth?  What sort of magic is “gravity” that it can glue people’s feet to the ball-Earth, while causing Earth itself to revolve ellipses round the Sun? How does gravity hold trillions and trillions of gallons of water to the outside of a ball earth while a child with little effort hops, skips and jumps right next to all that water on the seashore?   How do bubbles rise to the surface of water and gravity has no effect on them?  

Gravity is the blanket answer to all questions globalists cannot answer.  Yet, it is purported to cause weight, pull, push, spin, orbit, affect heavenly bodies and even cause things to act contrary to their nature. The theory of gravity, invented by a Luciferian worshiping Isaac Newton, is so full of holes, many honest scientists in the scientific community are abandoning it. One such scientist, Dr. Erik Verlinde is not an enemy of the globe, and he admits gravity is a lie.

"The unfolding story of gravity is like the emperor’s new clothes. “We’ve known for a long time gravity doesn’t exist,” Dr. Erik Verlinde says, “It’s time to yell it.”

Quote from: happenby

Broadly speaking a sextant is an instrument that measures the angle between two objects that are visible. Primarily, it is used to measure the angle between a celestial body and the horizon, a process normally known as sighting the object or taking a sight. The angle measured and the time at which it was measured is then used to identify the location of the user on the grid map of the world. Thus sextants are basically navigational tools and have been successfully used by seaman and even other travelers over the years. The most common process of this is to sight the sun at noon to find the latitude of one’s location.

Measuring the angle between two objects that are visible, which is the purpose of a sextant, has nothing to do with curvature.

Source, please?
Let me guess: you're just making this up.

Quote

Every measurement is based on lines, line of siight, mirriors, angles, parallel, and vertical. In fact, the mirrors must be maintained or the measurement will be off. Mirrors within reflect directly, and cannot reflect curve. Notice that identification of location is charted on GRID MAP. A grid map is flat. That they can translate these lines and angles to a globe is just another step. But its an unnecessary one, unless one wants you to believe you are on a globe.

But if the earth were flat, the angle between the north star, Polaris, and the horizon, would always be the same, regardless of latitude.

Maybe your failure to grasp that fact is why you think that the earth is flat.

No, I am not making this up.  The instrument itself denies that it can, with straight lines and angles, measure something that is curved.  That stands to reason.

Why do you say that the angle between the north star, Polaris and the horizon would always be the same regardless of latitude?  Are you making that up?  Naturally, if you change distance, an angle will change.  Period.  

I assume Neil is blabbering on about a sextant, but I have no idea what his point is. A sextant certainly does not show any curvature of the earth.

It appears to me that Neil has it in his head that this all has something to do with the globe because he doesn't understand the sextant.  He thinks the mention of the word arc assumes that a portion of the earth (for his purposes, a globe) is involved with the measurement, when in fact, the arc is a degree of a circle used in relation to angles and lines to denote distance and has zero to do with a globe earth.