Round Bottom Bottle

I have never seen this kind of glass bottles, so fascinating. 

According to Historic Glass Bottle Identification & Information Website on glass bottle bases 

Rounded bases were  designed to do the opposite of most bottle bases - to ensure that  the bottle was not left standing upright.  The point behind  the rounded bottom was to ensure that the bottle was left on its side so that  the wired down cork would not dry out and shrink allowing the contents to loose  carbonation and/or evaporate (Riley 1958).  The typical rounded base bottle was made of  thick heavy glass and used for carbonated soda, mineral water, and in  particular, ginger ale (Munsey 1970).  Some rounded bottom soda bottles  actually have a small flattened area in the middle of the base that allows for  the bottle to stand upright though somewhat precariously.  These are  referred to as "club" or "tenpin" in shape, "semi-round",  or "egg-shaped" (McKearin & Wilson  1978, Elliot & Gould 1988, Jones & Sullivan 1989).

These type  bottles are commonly referred to as "round bottom sodas" or "ballast bottles"  since it is believed (and may be true) that many of them were imported from  England as "ballast" (weight) in ships returning to the United States.  A  common variation is the "torpedo" bottle which is distinctly more pointed on the  end with an bulging "amphora-like" body.  The torpedo style was first used  in England at least as early as 1809 when a patent was granted to William F.  Hamilton.  These type bottles are often referred to as "Hamilton's" by  English collectors (McKearin & Wilson 1978).  Torpedo bottles are also  known by some as "bombs" (Elliott & Gould 1988).  A picture  of a typical pointed base torpedo soda bottle is pictured below right.  It  is embossed with "Walkden Aerated Water Co." (Manchester,  England) and dates from approximately 1880-1890.

Round bottom & torpedo bottles were usually  produced in a true two-piece mold where the neck, shoulder, body, and entire  base (and sometimes all or a part of the finish) were produced by the two halves  of the mold.  As such these type of bottles are simply a rounded  base version  of the "hinge" mold discussed earlier and exhibit one continuous mold seam that runs from one side  of the body, around the base, and then up the other side.

The majority of these bottles - round  bottomed or torpedo - date from  the 1870s to the 1910s, though there are some American made torpedo  bottles  (Eastern Seaboard) that date back as early as the 1840s (McKearin &  Wilson 1978,  Baltimore Bottle Club 2002).  Most have a blob style finish,  occasionally an oil or mineral finish, though some were made with a Codd  finish/closure and later ones (early 20th  century) were produced with a crown finish (Elliott & Gould 1988). 

I really want to see an image or an actual aerate bottle with liquid inside.