Georgian baluster stem wine glasses and many other 17th and 18th century English forms owe their form and existence to the slower cooling lead metal (lead crystal or flint glass if you prefer) developed at the Savoy glass house. The glass was not suited to the production of the earlier Venetian styles with thin and light funnel shaped bowls, although examples do exist. A baluster glass of the late 17th and early 18th centuries owe their distinctive style to necessity and English invention. Baluster wine glasses may be true balusters, the stem becoming progressively thicker towards the foot , or inverted balusters. There are a multitude of different stem types, swellings in the glass stem called "knops". These may be baluster knops, angular knops, drop knops, mushroom knops and there are some rare forms such as acorn knops, cylinder and egg types. Stems and knops occasionally contain tears and may also be hollow and occasionally contain coins within a hollow knop.
Early examples, prior to the imposition of taxes on glass, have a folded or domed foot or very rarely terraced and beehive feet. Those with less common knop types are avidly sought. There are examples in soda glass mostly continental and these are much underrated in my opinion.
Sizes vary from goblets that can hold a quart of wine to deceptive toastmaster glasses that hold a fluid ounce. As a rule of thumb baluster glasses became progressively smaller as the 18th century progressed. Engraved examples do exist but these are almost invariably later engraved. The most common bowl types are round funnel and bell shaped or waisted bowls.
Inverted balusters are the most pleasurable to use as they are both tactile and tend not to slip in the hand. These are iconic glasses and every eclectic collection should have one or two examples in lead or soda.