The sea breeze billowed the sails as a large ship sped forward. Waves crashed against its bow, shattering into spray that flew one or two meters high with a rushing roar.
Behind the ship followed dozens more large vessels with raised sails, closely trailing the flagship.
At the flagship's bow, Jiang Hao stood on the deck with an instrument in hand, observing the distant sea.
Ji Bu watched curiously as his lord fiddled with the strange device, occasionally peering through a small hole. Unable to contain his curiosity any longer, he asked, "My lord, what are you doing?"
"I'm using a sextant to determine our current position and make sure the fleet hasn't gone off course," Jiang Hao said.
"This little thing can tell us where we are? But all I see around us is endless ocean. How can you distinguish anything, my lord?" Ji Bu asked curiously.
"Simply put, I use this instrument to measure the angles between the sun, the stars, and the horizon. Then I calculate our longitude and latitude, which tells us where we are."
"Of course, measuring the angles alone is useless. You also need to know the sun's position at different times, the stars' positions on different dates, memorize the world's longitudes and latitudes, and use a formula to calculate the ship's location."
Ji Bu quietly swallowed.
That was the simple explanation.
Being bad at studying was truly painful.
"Don't underestimate this little thing. It took quite a bit of effort to make. Just the telescope on it took the craftsmen a long time. Grinding the lenses was one thing; the main problem was finding crystal so clear and flawless. Fortunately, I managed it. I even had an extra telescope made," Jiang Hao said with a smile.
Ji Bu still did not understand. He