Diamonds and purls

This represents yesterday evening's progress (~1.75 hours) on the sock from The Joy of Knitting:



Isn't it cute? I love the little purl-bump design that forms. There will be three diamonds, each one progressively smaller, and then just a line of purl bumps every other row down where the "middle" of the design would be, down the rest of the leg along the instep of the sock.