The world's first great bakers were the ancient Egyptians. Their large-scaled bakeries produced unleavened breads and cakes that were first baked on hot stones. The Egyptions were the first to discover how to use wild (natural) yeast to make the flatbreads and cakes rise. Round cakes descended from the round loaves of dough placed on hearthstones to bake. Whipping eggs to make cakes rise did not appear until another few millennia. By the 1840s, baking soda had been invented, followed by baking powder in the 1860s. It was with the invention of regulated temperatures in ovens and the more prevalent availability of sugar that led to more baking and increased creativity in the recipe department. The modern cake as we know it began to take shape in the mid-19th century.