William Stewart Bottle Stopper

U.S. Patent Numbers: 320,189                     Patented: June 16, 1885

U.S. Patent Numbers: 339,592                     Patented: April 6, 1886

William Stewart’s 1886 patent application was filed October 19, 1885 and specified:

I, William Stewart…of…Brooklyn…New York, have invented certain new and useful Improvements in Bottle-Stoppers, of which…

This invention relates to a new and improved self-acting internal stopper for bottles containing or intended to contain soda-water or other liquid charges with gases; and the objects are to produce a stopper which can be used in any bottle, which will be buoyant enough to float on the liquid and light enough to be lifted by the internal pressure to its seat in the neck of the bottle without requiring a lifting device or the bottle to be tilted or inverted, and which will not necessitate the use of any special kind of machine for filling or cleaning the bottle.

Heretofore internal stoppers, usually of a spherical shape, have been employed, and such stoppers may be divided into two classes – viz., first, gravitating stoppers, or stoppers of greater specific gravity than the liquid, and, second, floating stoppers, or stoppers of less specific gravity than the liquid.  Stoppers of the first class have heretofore consisted of a solid glass ball or a weighted hollow ball, and in some cases of a flat disk of pearl, ivory, or glass, and those of the second class of hollow balls composed of glass, porcelain, or sheet metal, and in some cases of a flat or nearly flat disk of several layers of cork or pearl or cork and india-rubber, or a ball composed of elastic material has been employed; but all such stoppers were objectionable in that they required special manipulation in filling and cleaning them, and, further, because to bring the stopper to its seat in the neck of the bottle, after the latter had been filled, it was necessary to use a lifting device or to tilt the bottle, so that the stopper would drop into the neck, thus causing a waste of liquid and gas.

By my invention I seek to produce a stopper which will obviate all these objections; and to this end my invention consists in a self-acting internal stopper, preferably composed of hard non-elastic material – such as vulcanized rubber – and which is buoyant enough to float on the liquid and light enough to be impelled to and seated against the packing-ring automatically by the gaseous pressure within the bottle without extraneous assistance or manipulation…

Figure 1 is a sectional view of an empty bottle supplied with my improved stopper.  Fig. 2 is a similar view of a bottle filled with the liquid.  Fig. 3 is a section of my improved stopper.

The stopper, a is composed of two semi-spherical shells, united to form a hollow ball.  I propose to make these stoppers of hard vulcanized rubber, as this is the only material I have been able to find from which it is possible to make a practically useful stopper of the requisite buoyancy and lightness.  I have found by careful practical experiments that is not possible to make a self-acting stopper from glass, porcelain, sheet metal, or elastic material, and that while cork is light enough for the purpose it is very objectionable, because it will rot, and thus render the stopper useless in a short time.

A stopper of elastic material, as heretofore made, is not light enough to be self-acting to close the bottle when the bottle is in the usual upright position during the filling process, and is too buoyant to roll into the neck to close the mouth of the bottle when it is inverted…(and)…unless they are of greater diameter than the inside diameter of the neck of the bottle they are liable to be blown out of the bottle by the internal pressure…

Stoppers composed of glass, porcelain, or sheet metal, besides not being self-acting, are objectionable, because of the liability of breakage of the bottle or the stopper during the washing, filling, or emptying of the bottle, and, further, because they require a bottle of special construction to prevent the stopper from rolling back to its seat in the neck when the liquid is being poured out…

A floating stopper composed of a flat or nearly flat disk is objectionable, in that it is difficult to get such a stopper properly seated, as it requires a special construction of the neck of the bottle to make a gas-tight joint.

In Figs. 1 and 2 of the drawings I have shown my improved stopper in connection with a bottle supplied with a cap of the construction described and claimed in…Letters Patent No. 320,189, granted to me June 16, 1885…

In these (1886) figures of the drawings, a designates the stopper, b a soft packing, and c a metal cap.  The packing is ring shaped, and is laid over the edge of the mouth of the bottle, and held there by the cap, which has a central aperture, d.  This cap is provided with arms which are bent around a fastening wire, e, which encircles the bottle neck.  The bottle itself is of ordinary construction, and the stopper of less diameter than the inside diameter of the neck.  When the bottle is filled, the stopper a rises to the surface of the liquid, and is then lifted by the internal pressure to its seat against the packing, thus closing the bottle.  When the liquid is to be poured out, the stopper is pushed from its seat by means of a rod or other suitable implement, and rises through the liquid to the highest part of the bottle, when the latter is tilted or inverted to discharge its contents. 

My improved stopper, with a ring-shaped packing and aperture cap, can be applied to any bottle, and the bottle can be filled by any ordinary bottling-machine in the market, thus enabling a bottler of soda-water or other liquids charged with gas to utilize bottles which are now practically useless, resulting in a saving to the bottling trade of many thousand dollars every year.


William Stewart’s patent specifications outline many of the challenges bottlers and customers faced, and in combination with the illustrations provide a fairly easy-to-understand description of his stopper’s design and how it functioned.  Once the patent was approved, a Stewart Bottle Stopper Company advertisement in an 1886 issue of the National Bottlers’ Gazette proclaimed:


The Self-Acting Floating Ball Stopper is a light, hollow ball, a mere shell, but strong enough to bear the weight of a man and hard enough to withstand the action of acids.  It is, therefore, impervious and will not contaminate the beverage…

DIRECTIONS TO FILL – To fill these bottles you simply place it right end up, like you would fill a bottle with a cork, and place a cork in the cylinder, and instead of driving it you leave it remain, to prevent the flow of water up through the cylinder.  That is all there is to it.  It is just as easy and as simple as rolling off a log.  See the point?  When you desire to open a bottle, when it is freshly bottled, with the foam filling the neck, use an opener to force the ball to the liquid.  After the foam has subsided, you can drop the ball to the liquid by one quick motion of the forefinger.

Bottles utilizing Stewart’s 1885 patent stopper are known, but we’ve yet to see an example matching the Self-Acting Floating Ball Stopper bottle as illustrated and described in his 1886 patent.  Historical research has yet to fill a major gap in this story, as there certainly appears to have been an as-yet-to-be-determined business relationship between William Stewart, Selden Twitchell (of the Twitchell Bottle Stopper Company of Philadelphia, Pennsylvania), and William Roorbach.    

In 1885 the Twitchell Bottle Stopper Company was advertising “Twitchell’s Self-Acting Floating Ball Stopper.”  Less than a year later, an identical closure was being marketed by the Stewart Bottle Stopper Company of New York City as “Stewart’s Self-Acting Floating Ball Stopper,” with the bottles listed as being made by The U.S. Bottle Manufacturing Company of Findlay, Ohio as sole licensee.  The bottle illustrations pictured below were used with 1885 Western Bottler Twitchell and 1886 National Bottlers’ Gazette Stewart advertisements.  Not only are the similarities obvious, both bottles appear to be identical to William Roorbach’s June 23, 1885 patent!  The Roorbach patent was co-owned by Selden Twitchell, so the patent date on the illustrated Twitchell bottle is understandable.  Mysteriously, however, the Stewart bottle specifies his April 6, 1886 patent date, yet the illustrated bottle doesn’t come close to matching his patent specifications.  These comments will be updated if/when we determine exactly how William Stewart fits into the picture. 

The floating-ball stoppers promoted by Twitchell, Stewart, and Roorbach achieved limited marketing success with bottlers across North America.  Twitchell’s stopper was the most prevalent of the three, perhaps due to the “laundry list” of benefits-type advertising copy they employed.  This text from Twitchell’s 1885 advertisement provides numerous clues to the many challenges faced by bottlers and customers:  



1 – It can be filled and stoppered with any Bottling Machine, hence no expense in adopting it.

2 – It is filled and stoppered quicker than cork or any other patent stopper.

3 – It has no metal about it to contaminate beverages with metal poisons.

4 – It has no soft rubber to come in contact with or to contaminate the beverages with obnoxious flavors or odors as with all other patented stoppers.

5 – All parts of this stoppered bottle can be washed quickly and thoroughly with brush, shot or any bottle-washing machine.

6 – It has no protruding stopper to be knocked down by placing filled cases on top of each other, therefore much more safe.

7 – It is more quickly opened than any other stoppered bottle, and as the ball quickly leaves the mouth when opened, there being no obstruction in the mouth of the bottle, the beverage flows out quickly, without any agitation at the expense and loss of carbonic gas.

8 – This bottle has no crevices or irregularities about it to prevent its thorough cleansing in every part.

9 – No flies or dirt can get into the bottle after being emptied, to rot and breed maggots, if, after being washed and drained, it be placed in box or case, mouth downward, as the ball drops to the mouth and prevents flies or dirt from getting into it.

10 – It cannot be used for spirituous liquors of any kind, nor for root beer or ketchup.

11 – When properly filled about to the shoulder, even though frozen solid, the bottle will not break if thawed out in cool water.

12 – The bottles for our Patent Stopper can be made in private moulds that are used for making bottles for cork or any of the metal spring stoppers, by enlarging the part of the moulds that forms the neck of the bottles.

13 – Our Patent Floating Stopper is of such shape and material as to withstand all wear without being broken; hence there are no repairs or replacing of parts at considerable expense and labor, as this is with all other patent stoppers for same purposes.

14 – Our Patent Floating Stopper is so little affected by wear that it will outlast one hundred of the metal spring style of stoppers.

We supply Special “Finishing Tools” so any Glass Factory can make Perfect Bottles

Price of Twitchell’s Floating Ball Stoppers, Fittings Complete, $2.25 per Gross.  Our Hard Rubber Floating Ball Stopper, $1.25 per gross.  Our Patent Rubber Bushing, $1 per gross.

The Twitchell Bottle Stopper Co.,

221 Vine St.,       Philadelphia, Pa.