We’ve just returned from three glorious days of seaside frolicking at Boggle Hole in Robin Hood’s Bay. Within moments of arriving, I dawned on me that I’d made a huge mistake and neglected to buy Clarence Ellis’ rock-spotter’s guide The Pebbles on the Beach. Faber's beautiful new edition, designed by Alex Kirby and illustrated by Eleanor Crow, has a wonderful fold-out jacket for easy reference and would’ve really come in handy for imparting some geological wisdom to my boy.

In its absence, he had to make do with my own home-brewed classifications, such as:small pebble; largish pebble; black pebble with a stripe; pebble that is probably a new potato; don’t touch that pebble, a dog made it; and fossil it’s a fossil FOSSIL no wait it’s seaweed.