Preheat the oven to 350 degrees. Place the butter in a 9 x 13-inch baking dish and place the dish in the preheating oven.
In a small bowl, combine ½ cup of the sugar with the cinnamon and mix well. Set aside.
In a medium bowl, sift together the flour, the remaining 1&frac1/2; cups sugar, the salt, and the baking powder. Blend in the milk, stirring just until the mixture forms a batter.
When the butter in the baking dish has melted, remove the dish from the oven and pour the batter into it.
Spoon the peaches and their juice on top of the batter and sprinkle with the reserved sugar and cinnamon mixture.
Bake for 35 to 45 minutes, until the peaches are bubbling. As the cobbler bakes, the batter will rise up around the peaches.
Remove from the oven and allow to cool for about 20 minutes before serving.