As we sail across the Atlantic toward Miami from Tenerife, in the Canary Islands off the coast of Africa, the ocean often seems nearly flat, but the swells are powerful enough to rock our 694-passenger ship. It’s not a violent movement. It is a motion that never stops.

During the first crossing night, as we left the craggy volcanic mountains of Tenerife, beginning the 3,135-mile run to Miami, I slept like a baby.

Goodbye Europe, heading west from Tenerife:

Our voyage on Azamara Journey is steady, measured, and relentless.

At a speed of about 20 miles an hour, we are creeping across the Atlantic. You go to bed at midnight, wake at 8, and you’ve got another 160 miles of ocean behind you. You get on the treadmill in the gym for 30 minutes, and when you get off, you are 10 miles closer to Miami.

We are not taking the shortest course to Nassau in the Bahamas, which will be the first land we see after seven days at sea.

Sailing a little bit south

As sailors know, the shortest distance between two points is not a straight line. The earth curves. In the Northern Hemisphere, the shortest distance between two points – such as the Canary Islands and Nassau – would take the ship on a curve that would bend north.

North is not the best choice in late fall, not if you are hoping for sunshine and your passengers enjoy sitting outside for breakfast and lunch, at Windows Cafe, right.

Captain Jason Ikladis and his staff have plotted a more southerly course, which is a straight line, or rhum line, toward Nassau.

As Captain Ikladis explained, the rhum line will be only about 40 miles longer than a course following the Earth’s curve. Besides, he said, as you sail farther south you may pick a westerly current that will move the ship slightly faster. So, the overall cost in time on the longer route probably is minimal — well worth any added temperature.

Next: Why the port side is sunny on Azamara Journey

David Molyneaux is editor of TheTravelMavens.com