The above is an English mallet and dates from about 1720 to 1750. Certainly, we are finding pieces of this style.
This pictures shows the pontil or base portion. These bottles were all hand blown with a tube attached to the base while the glass was still molten. Once formed, the tube was broken off and the scar left behind was sometimes sanded smooth. Earlier onion style bottles were not smoth and left a jagged pontil scar. Yes, they can still cut you!
Just prior to the American Revolution, bottles began to take on a more cylindrical appearance like the one shown above. This style was prominent until just prior to the Civil War.
The above bottle shows a new way of making bottles. While the molten glass was still blown by hand, it was blown into a mold of two or sometimes three sections. This is obvious by the seam lines that are visible along the sides or neck. The tops were always applied separately.
After about 1900, bottles were machine made and most were made from colorless glass. These are easily recognized by the seam running up the side all the way to the top of the bottle.
Perhaps we can find some of these bottles intact if we find ourselves excavating a cellar this summer. It's always exciting to find any artifact intact!