Complex sentence: The design of the Herodotus machine does not go into more depth as to what it looked like; however, Leonardo da Vinci is said to have sketched a machine that he believed to be the machine Herodotus described.
Split into simpler sentences: The design of the Herodotus machine does not go anymore in depth as to what it looked like. However, Leonardo da Vinci is said to have sketched a machine that he believed to be the machine Herodotus described.