"The History of Technology" makes my head big

I read the shipbuilding part of "History of Technology" during the day, and it was written slowly, and there was a bit of work to do at night, so I'm sorry for not changing it today. A colleague recommended a good book "All-round Athlete". I also want to watch Monday 10th! It's a pity that the concubine can't do it! (To be continued.) )