A near extinction level event strikes the earth, humanity is devastated and left with just a handful of hardy survivors. How will a small group of survivors not just survive but how can they rebuild modern civilization from the ashes? Lewis Dartnell's The Knowledge tries to answer this question and serve as a guidebook for restarting civilization.
The beginning of the book covers how, without routine human intervention, infrastructure quickly begins to rot. Survivors will need to scavenge and scrape to get by. Once able to survive Dartnell describes the processes of rebuilding agriculture, basic chemistry, all the way to getting metal out of rocks, elaborate electrolysis processes and creating medicines like penicillin by isolating penicillium mold.
I really enjoyed the first chapters where the basics are covered. I learned a bit about agriculture, using kilns to create materials like concrete and pottery, making paper, fertilizer, soap, and generating electricity. The later chapters covering advanced ideas such as medicine and photography were interesting but harder for me to grasp.