When was bubble gum invented?

In 1848, John B. Curtis made and sold the first commercial chewing gum called the State of Maine Pure Spruce Gum. But William Finley Semple Was the First Person to Patent chewing gum in 1869. However, Frank Fleer was the person credited with inventing the first bubble gum called Blibber-Blubber; which was never sold! In 1928, Walter Diemer of the Fleer company was able to perfect the treat we know today as "Double Bubble" bubble gum. All information was found at about.com; more on the history of gum can be found there.