Book review of TUBES- In 2009, a squirrel chewed through a wire in Andrew Blum’s back yard, slowing his broadband to a trickle and propelling him to begin a quest to find out what the physical nature of  what the internet actually is. He goes beyond the concept of the internet into what is it in tangible hardware on the ground. What didn’t exist in 1972 that is in existence now? He recounts the compelling story.