How were earlier navigators knowing their positions when no GPS was there ?

Question

How accurate was the earlier systems?

Answer 1

The standard 19th century method was by "shooting the Sun" using a sextant and chronometer.

The navigator had a chronometer (a very accurate watch) that kept the local time at Greenwich, England. Every day at sea, as local noon approached, the navigator would "shoot" the sun with a sextant, to measure the sun's "altitude", or angle above the horizon. With each shot he made note of the exact chronometer time and the altitude. At some point, the sun stopped getting higher and started getting lower; that point marked "local apparent noon".

The time of local apparent noon, according to the chronometer, would tell you your longitude, and the altitude of the Sun at the time of local apparent noon would tell you your latitude.

For a skilled navigator, this method was accurate to within a half a mile or even less.

Answer 2

More often sailors would have to go close to the land
to follow landmarks around the coast.

But if they were going further then they would need to use the stars and the position of the sun. As long as you know the time you don't need GPS.

Answer 3

That was the problem
You plan to sail to your european neighbour and the next thing you know you are in America.
The trick was to sail away from land in a straight line for a certain amount of knots and then turn back.
If you got it wrong you just fell off the edge of the Earth.
Imaging how many ships sunk.
And the locals in the pub would say "if they ain t back by now then they fell off the edge of the Earth me harties"
So my answer is they just travelled short distances in a straight line.

Answer 4

they used the SKY ... STARS.
as accurate as the changing Seasons allowed.