Charles Hermann began manufacturing his pottery in Milwaukee, Wisconsin in 1856. His son-in-law Louis Pierron joined the company in 1882 and the name changed to The Chas. Hermann Stoneware Co. That dates this mark from 1856 to about 1882-3. "C. HERMANN MILWAUKEE" in an oval is the stamp used on Hermann's pottery, although not all the undecorated pieces like this one were marked. The mark is above the shoulder of the jug on the opposite side from the handle.
The beehive shape of this jug is covered with an extremely dark brown, matte Albany slip glaze, almost black, which marks this as an early Hermann piece from the 1850's-1860's. His later undecorated pieces made in the 1870's have a light brown/tan glaze. The glaze coats everywhere except the bottom, which has just some swipes of the glaze. The applied strap handle curving from the mouth of the jug ends in a fish tail shape where it meets the body of the jug, typical for Hermann's jugs.
The one gallon jug stands 10 inches tall, has a base 7 1/2 inches in diameter and weighs 6 pounds 10 ounces. It took a hard knock sometime in its past that took a chunk out of the bottom, which is unseen when the handle is turned to the left. There is also a hairline radiating out from that divot which has not traveled to the upper surface and another hairline in the oval mark (all of this is shown in our photos). Other than those flaws and a few nicks in the glaze, the jug is in good shape and displays handsomely.