This section is from the book "A Treatise On Beverages or The Complete Practical Bottler", by Charles Herman Sulz. Also available from Amazon: A Treatise On Beverages.
Since the introduction of the syphon from France, for the dispensing of mineral waters, there have been few material improvements on the original construction of the "head" or syphon proper, until recently, and these latter improvements have not been very distinct in their differences from the old ones in use.
Fig. 300. - Sectional View of French Syphon Heads.
All have worked well, however, and their use is spreading in the trade, and each year witnesses its adoption by scores of bottlers. It is a popular method of dispensing plain charged waters, and its great and obvious advantages, and the growing favor wherein the syphon is now evidently held by the mass, has been always advocated. Most certainly the syphon, at once elegant, convenient and economical, richly deserves the favor in which it is now held, and we are quite sure that no better means for taking refreshing drinks in hot weather, or, indeed, in any weather, can be devised, and this the more particularly for the private-house trade.
The principal objections raised against the syphon have been the facts that the beverage in being discharged is subjected to so much friction in its circuitous route, which causes the loss of a large proportion of its gas, and that the parts composing the syphon head were so complicated as to easily get out of order, causing leakage. These objections have been remedied to a great extent in some of the accomplished improvements.
The syphon consists of a glass bottle to which a metal top, forming a tap, is attached. The syphon is filled at a high pressure - 120 to 140 lbs. - with carbonated water, and is so disposed that, when the tap is opened, the liquid inside it is forced out by the internal pressure of the carbonic acid gas.
Fig. 301. - Sectional View of Improved English Syphon.
The American manufacturers have also made various improvements in the construction of syphon heads, and the carbonator will have the choice which style to approve.
It will readily be understood that the bottles require to be of very great strength to resist the heavy internal strain, and at the same time the metal fillings must be such as in no way to contaminate the liquids contained. These are points which require the most careful attention, for the consequences of imbibing carbonated waters contaminated with lead may be very serious.
The syphon head should be made of pure block tin, with no lead or other injurious metal in it. The glass must be clear and brilliant, which adds greatly to the appearance of the charged water.
To remedy the foaming of beverages and loss of gas when drawn from a cock dispensing at the counter is the object of one of the American patents. An English manufacturer has introduced this improvement into the syphon bottles, as illustrated here, with the introductory remark, that it has been found by experience in drawing soda water from a cock or syphon in the usual manner that a great part of the gas is entirely wasted, owing to the small stream which issues from the jet being exposed to the action of the air. The effect of this is that the water never has the full strength due to the pressure at which it has been manufactured, and soon becomes flat and tasteless.
Fig. 302. - New Syphon Spout.