(Happy Children's Day to all!)

φ=δ±（90°-H）

H is the noon solar elevation angle, which can be measured by the midday shadow.

δ is the current latitude of the direct point of the sun, even if you don't know, you can also calculate it by date - the angle of the yellow and red intersection is 23.5 degrees, the vernal equinox day is March 21, at this time the height of the direct point of the sun is 23.5 degrees, although the earth's orbit is elliptical, but the long and short semi-axis of the ellipse is very close, it can be simply defaulted to a circle, it is now summer, calculated from the day of the vernal equinox, it can be simply defaulted to move 0.25 degrees per day.

Even, with the help of solid geometry calculations, this value can be made more accurate.

In this way, it is possible to deduce the geographical latitude φ where the ship is located at noon on that day.

Longitude can be determined by adding or subtracting from the local noon time difference on the day using a watch.

The gap of knowledge cannot be bridged by experience, as the current hegemon of the Caribbean, Barbossa's sailing experience is definitely the best in the world, but even he cannot confirm the ship's position without relying on charts.

The so-called nautical charts, which no one can understand, simply refer to the determination of directions by constellations and dates.

......

"Jack~" Barbossa greeted Jack affectionately.

"Hector!" replied Jack affectionately, not in the slightest disillusioned by the terrifying pirates around him and the man in front of him who had almost killed him, as if he were at home.

The reason why the two rivals were able to face each other so calmly was mainly because of one person.

At this time, the moon was in the middle of the sky, and it was already halfway through the night, and the Black Pearl floated on the surface of the sea in Port Royal Harbour, gently undulating with the waves.

There was no shelling of the harbor, and the notorious terrorist pirate ship of the last decade was docked on the dock inside the harbor, and the harbor batteries did not fire at the Black Pearl.

The main reason for such a harmonious picture is that the harbor below is beckoning the boy who is constantly carrying raw meat to the ship by a group of Royal Navy soldiers.

Hei needs to eat meat, and God knows that they will have to float at sea for a few days on the long journey, and they must prepare enough meat for Xiaolong.

As for the source of the meat, after a cordial and friendly conversation between Karl and Governor Swan, Governor Swan enthusiastically expressed his willingness to give Carl a whole shipload of raw meat for free on behalf of all the military and civilians of Port Royal.

Karl tried every means to shirk it, but in the end, he gritted his teeth and reluctantly accepted it.

Looking at the expression on Governor Swan's face that he was almost crying with joy, Karl's heart sighed more and more.

What a good guy.

With the joint efforts of the entire Royal Navy in Port Royal, the Black Pearl is gradually being filled with fresh cattle and sheep, the smell of fresh manure fills the whole ship, and the draft of the hull is gradually being pressed close to the waterline.

In this way, the legendary pirate ship was turned into a cargo ship for transporting livestock by Carl.

"I have a question, Jack. ”

Looking at Carl standing on the dock, Barbossa asked Jack beside him curiously.

"How did you meet this boy?"

Jack turned his head to look at Barbossa and smiled mysteriously, "I'm Captain Jack Sparrow. ”

Of course, he won't tell his sworn enemies about the shame before, don't look at the two of them being so harmonious now, but in his heart he can't wait for the other party to die in front of his eyes immediately.

"It's still the same rhetoric, Jack. "To tell you the truth, I find it strange that a pirate like you, who is stupid and cowardly, but who has done nothing, can survive every time...... Sometimes I wonder if you're the son of Lady Luck. ”

"Aha!" Jack's eyes lit up and he looked at Barbossa in surprise, "I can't believe that Hector, who looks so ugly, can come up with such a beautiful nickname - Captain Jack Sparrow, Son of Lady Luck." ”

"Nice name, I laughed. ”

Despite knowing that the other party was deliberately angry with him, Barbossa couldn't help but roll his eyes, and was about to say something sarcastic, when a gentle voice sounded behind the two of them.

"Two, it's almost, let's go. ”

The two turned around, and Carl was already standing behind them.

The boy had a small dragon lying on his left shoulder.

In the sky, at the top of the Black Pearl's mainmast, a crow and an owl were standing on either side of the crossbar of the mast, looking down on the deck below.

Barbossa and Jack nodded at the same time, saying in unison.

"As you wish, sir. ”

As soon as the words fell, the two looked at each other strangely.

Seeing this, Carl couldn't help but laugh.

"The relationship between the two of them is really good. ”

As soon as the words came out, as if electrocuted, Jack and Barbossa's gaze immediately separated from each other's gazes.

......

"Adjust the ...... of the sail" - "Adjust the ...... of the sail"

"Unswivel halyards and halyards ......" – "Unswivel halyards and halyards ......"

"Pull up the flag line, prepare to anchor ......" - "Pull up the flag line, prepare to anchor ......"

One after the other, Barbossa and Jack shouted orders from the deck.

When the two finished the last sentence almost at the same time, they immediately looked at each other angrily.

"What are you doing?" Barbossa yelled at Jack.

"What are you doing?" said Jack, not to be outdone.

Barbossa was about to fight back, but was surprised to find that the pirates on board had not moved at all.

If it was just Jack who was ordering, it was normal for them not to move, but just now he was also ordering, but none of the pirates on the ship moved, which was a bit abnormal.

"What are you waiting for, you idiots, don't you hear your captain already giving orders?" he shouted.

However, the pirates did not move.

Even, this group of people didn't look at him at all.

"Haha! they won't listen to you as soon as I get on the boat, Hector, I'm the real captain of this ship!" Jack said happily along.

Although it was strange that the pirates who had betrayed him had changed their minds at this time, it seemed to Jack that it was the only possibility.

However......

"Actually," Carl smiled embarrassedly at Jack and Barbossa, standing beside them, "I think they're waiting for me." ”

Ignoring the somewhat stupid Jack and Barbossa, he waved his hand at the pirates who looked hideous but kept flattering him, and said flatly, "Let's go." ”

"Yes, Captain!"

The pirates replied in unison.

The voices were unequivocal and unanimous, ignoring Jack and Barbossa's eyes that almost popped out of their sockets when they called Carl.

They methodically hoisted their sails and anchored.

Looking at this scene, Jack and Barbossa opened their mouths wide in a daze, and didn't say a word for a long time.