1) A2K Handbook, free online, http://a2knetwork.org/handbook

"Access to Knowledge (A2K) is the umbrella term for a movement that aims to create more equitable public access to the products of human culture and learning. The ultimate objective of the movement is to create a world in which educational and cultural works are accessible to all, and in which consumers and creators alike participate in a vibrant ecosystem of innovation and creativity."

2) Sci-Fi author L. Sprague de Camp's 1963 book, "The Ancient Engineers", covers the period from early Egyptian engineering up to Galileo. http://www.amazon.com/Ancient-Engineers-L-Sprague-Camp/dp/03...

“History, technology, culture, finance, and sociology intersect here. It’s not history from the top (kings and such, which some say is dry), nor history from the bottom (average people, which is necessarily endless and perhaps not very revealing). It’s history from the nuts-and-bolts middle – how structures were built, how materials were transported, how wars were fought. When you know this sort of foundational information, everything else becomes more real.”

3) Paul Calter, "Squaring the Circle: Geometry in Art & Architecture", http://www.amazon.com/Squaring-Circle-Geometry-Art-Architect...

"the combination of the subject knowledge of design, architecture, art, geometry, philospohy, music theory, and mathematics ... Calter includes the basic lessons and explanations of a regular Geometry course in his book, but then he interweaves an integrated classical curriculum (based on deductive reasoning)"

4) Georges Ifrah, "Universal History of Numbers", http://www.amazon.com/Universal-History-Numbers-Prehistory-I...

"the first complete account of the invention and evolution of numbers the world over ... Dubbed the "Indiana Jones of numbers," Georges Ifrah traveled all over the world for ten years to uncover the little-known details of this amazing story. From India to China, and from Egypt to Chile, Ifrah talked to mathematicians, historians, archaeologists, and philosophers."

Pick a random interesting page from a reference below, then use a search engine to find and connect with people who care about the topic:

Harper's dictionary of classical literature and antiquities, https://archive.org/details/harpersdictiona00peckgoog

David Rumsey Map Collection (includes old "maps" of human knowledge, today could be called infographics), http://www.davidrumsey.com

The Ancient Engineers, by L. Sprague de Camp, http://www.amazon.com/The-Ancient-Engineers-Sprague-Camp/dp/...

Oxford English Dictionary, 1888 Edition, 15000 searchable pages as a Windows app, https://archive.org/details/oed11_201407

Sci-Fi author L. Sprague de Camp's 1963 book, "The Ancient Engineers", is also worth a look, from early Egyptian engineering up to Galileo. From an Amazon review: “History, technology, culture, finance, and sociology intersect here. It’s not history from the top (kings and such, which some say is dry), nor history from the bottom (average people, which is necessarily endless and perhaps not very revealing). It’s history from the nuts-and-bolts middle–how structures were built, how materials were transported, how wars were fought. When you know this sort of foundational information, everything else becomes more real.”

Review: https://www.kirkusreviews.com/book-reviews/l-sprague-de-camp...

Preview: http://www.amazon.com/Ancient-Engineers-L-Sprague-Camp/dp/03...

Excerpt: "Everybody has heard of Julius Caesar - but who knows about his contemporary Sergius Orata, the Roman building contractor who invented central indirect house heating? Yet Orata has affected our daily lives far more than Caesar ever did." (http://en.wikipedia.org/wiki/Sergius_Orata)