Manufacturing Carbonated Water

Although bottle filling machinery and bottle stoppers evolved considerably during the second half of the nineteenth century, the process of manufacturing carbonated water changed very little.  Two methods of carbonated water production evolved, known as the “English Continuous System,” and the “Standard American System.”  The basic difference between these two approaches was the way in which the water was carbonated.  The English system enabled bottlers to fill bottles indefinitely, stopping only to recharge the acid and marble dust in the generator.  Water was drawn continuously into the generator with only occasional adjustments to pressure valves.  The American system required refilling of the water cylinders when they were empty.  If a cylinder was dry, water couldn’t be added without wasting the remaining carbon dioxide it contained.  Although the American system required additional maintenance, it was the predominant approach used by U.S. bottlers because much higher carbonation pressure could be attained. 

In order to bottle with the American system, the cylinder was filled three-fourths full of water.  Then several pounds of marble dust (calcium carbonate) and bicarbonate of soda (to keep the marble dust dissolved evenly, soften the mass, give it a smooth, lump-free texture, and cause the gas to be more freely generated) were introduced into the marble chamber, along with enough water to aid in agitation of the mass.    Next, a quantity of sulfuric acid was poured into the acid chamber and then released into the marble chamber by means of the acid valve.  As the agitator wheel was turned slowly, the gas was released from the marble dust and flowed thru the gas pipe and into the cylinder.  This gas dissolved in the water producing carbonated water.  James W. Tufts’ 1888 book, The Manufacturing and Bottling of Carbonated Beverages, listed “Marble-Dust.  Price per barrel, delivered free on board in New York, $1.50.”  The W. H. Hutchinson & Son Manufacturers and Dealers in Bottlers Supplies catalog for 1889 advertised marble dust “by the barrel or carload,” and sulfuric acid “by the carboy or carload.”

As the gas supply decreased, more acid could be let into the marble chamber to react with any remaining marble dust.  Once the water in the cylinder was charged to the desired pressure, the discharge valve was opened and the carbonated water allowed to flow thru a hose to the bottling table.  Due to the corrosive nature of sulfuric acid, generators were always rinsed thoroughly with fresh water.

Generators were typically six to seven feet tall and weighed 1,000 pounds, with larger ones weighing as much as four tons.  They were easily kept in working order, but when damaged often required shipment to the manufacturer for repairs.  Most damage involved collapse of the block tin or lead lining due to a sudden reduction in pressure.  Foreign objects in the marble dust also tore the lining or bent agitator blades.  The greatest operating danger posed by generators typically occurred when the wrong valve was accidentally opened or closed, causing the internal pressure to rise, exploding the generator and spraying the acidic contents.   

The safe and successful operation of carbonated water generators required a thorough understanding of how this sophisticated machinery functioned.  For those seeking additional details, James W. Tufts’ 1888 book, The Manufacture and Bottling of Carbonated Beverages, provides highly detailed descriptions and operating instructions for setups of one generator with one, two, or three cylinders, and several other configurations.  The accompanying illustrations show a typical installation (note the tools) and a sectional view revealing the inner workings of the cylinder, and acid-chamber, and a purifier.  Tufts produced cylinders of both iron and copper, with both styles having block tin linings.