chapter 1 How many sweets in the jar? -- chapter 2 Loose change and tight packing -- chapter 3 Hard problems with hard spheres -- chapter 4 Proof positive? -- chapter 5 Peas and pips -- chapter 6 Enthusiastic admiration: the honeycomb -- chapter 7 Toils and troubles with bubbles -- chapter 8 The architecture of the world of atoms -- chapter 9 Apollonius and concrete -- chapter 10 The Giant’s Causeway -- chapter 11 Soccer balls, golf balls and buckyballs -- chapter 12 Packings and kisses in high dimensions -- chapter 13 Odds and ends -- chapter 14 Conclusion.