In the early 1970s, Hasbro introduced a new line of roly-poly toy called Weebles. Egg-shaped figures small enough for a youngster's hand, Weebles wobbled in just the right way to make a kid chuckle. For a precocious child, there is a lesson in gravity in the way Webbles work, but really, Webbles are just too much fun to worry about how they work. Since 1971, more 115 Weeble characters have been introduced, in addition to about 40 figures in the line of larger Weebles it introduced in 2010. To add play to the figures, Hasbro created scores of play sets for Weebles including vehicles (Wehicles), buildings, and furnishings, and many themed sets named after children's everyday activities and characters from children's books. Advertising for Weebles uses the catch phrase: "Weebles wobble, but they don't fall down."