This book is in the rarified genre of reluctant memoirs. As a man who grew up without grandparents, thinking that was something for other people, Jones needed a violent, literally earth-shaking reason to start looking into his family's past. I love the way Jones sees metaphors in everything around him, constantly writing the world. He sees a woman gardening against the backdrop of a destroyed city and asks whether we are solving the right problems as we go about our lives. He learns of the liquified foundations of a city built on a drained swamp (Christchurch), and wonders what the foundations of his identity are. So unless you're willing to wander in the world of metaphor with him, some of this may not make sense to you. But I loved it.
His parents were both abandoned children, termed "orphans" although their parents were not technically all dead. So the identities of his grandparents and their personalities are more mysterious to him than they are to most people. He traces back to their lives, trying to find their cores. The title is both literal and metaphorical -- he describes his father as someone who hardly ever speaks, and his history is silent because of its mystery.
Anyway, this is a very different sort of memoir than even most authors write (and most who write memoirs have not lived their lives as writers). He has been resisting questions about his past for a long time, so he's not sure where this investigation will go or whether he wants to know what he will find. It's full of metaphor, of questioning, and of vulnerability, and therefore a bit of discomfort. I found it a very interesting read.