The Mariner’s astrolabe improved navigational technology. Before the Mariner’s astrolabe people used the cross staff and the quadrant. But there was a problem. The boat would rock so it would be hard to keep a straight eye on the stars. The Mariner’s astrolabe was made of heavy brass with holes cut into the centre of it so the wind could go through it.
Double entry Bookkeeping
Double entry bookkeeping makes it that every transaction recorded, two entries will be made instead of one. Luca Pacioli made double entry bookkeeping popular by writing a book. He made the book easy for people to understand. It led to grow the economy.
Luca Pacioli was interested in arithmetic from a young age. He wrote many books but his most famous book was about double entry bookkeeping. Even though people knew about double entry bookkeeping Luca Pacioli wrote about it in a way that people understood.
Leonardo da Vinci
Leonardo da Vinci was born into a rich family and was naturally gifted. Leonardo was taught by a great painter, and when he was 20 he was entered into the drawing guild, and his father opened up a shop for him to sell his art in. He was supported by many wealthy people including the King of France who invited him to France to paint. He was an amazing painter and he also invented things but he was much better at art. But he had one problem, he could not focus.