Hero (or Heron) of Alexandria

Hero (or Heron) of Alexandria (c. 10–70 AD) was an ancient Greek mathematician and engineer  who was active in his native city of Alexandria,  Egypt. He is considered the greatest experimenter of antiquity and his work is representative of the Hellenistic scientific tradition. Most of his writings appear as lecture notes for courses in mathematics, mechanics, physics and pneumatics. Although the field was not formalized until the 20th century, it is thought that the work of Hero, his automated devices in particular, represents some of the first formal research into cybernetics (wikipedia). For some he is the spiritual father of Leonardo Da Vinci.

Hero's explanation regading Eupalinos tunnel alignment