Four years ago, when my daughter was born, I learned that the National Health Service sends a midwife to the home of every mother within a week or so after she leaves the maternity ward. It's a friendly visit to make sure she is recovering and her new baby is thriving. The midwife arrives with a backpack full of equipment, including this portable baby scale. When she pulls it out, it looks like a pillowcase with a metal hook--mildly sinister, and not something you would want anywhere near your baby. But these ladies have a way of inspiring confidence, and before you know it you're smiling at the cleverness of the contraption. Henry didn't wake up for his big weigh-in. He didn't even wake up for the heel-prick test, in which blood was drawn from his heel to screen for a handful of diseases and genetic conditions. And thanks to the visiting midwives of the NHS, all this could be done without loading him into his carseat and taking him out into the cold.