Why did it used to be harder to sail over deep ocean, compared to shallow waters

Question

Why did it used to be harder to sail over deep ocean, compared to shallow waters

In: 152

Answer 1

There is a great book called Longitude by Dava Sobel that gets into the big problem of deep ocean travel: that you can’t really tell how far east or west you are without landmarks to navigate by so it’s challenging to tell your longitude exactly on long distance voyages at sea. Only a few cultures found methods to mitigate these problems before sea clocks were invented.