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.
This style or finish of fountain should never be used for making or storing carbonated water. The lining should be done with heavy tin sheets, seamless, consist of two sheets only, or, what is best and more preferable, they should be lined with rolled block-tin. No soldered linings should be accepted, as the solder, being never pure tin, will contaminate the beverages. A good tin lining will also strengthen the fountains. The agitators in fountains must be covered with block-tin, the bearings of substantial thickness, and their exposed parts protected against the highly solvent action of water, charged with carbonic acid gas. The pipes and valves connected with the apparatus must be of pure tin.
Silver-lined fountains are the best for wine and cider. Porcelain or glass-lined fountains would be the most desirable for all purposes, but the great liability of these linings to crack is a serious objection to their employment.
The American apparatus must be tested in regard to its capacity of pressure before leaving the factory. It should be tested to stand at least double the pressure ordinarily required: 400 to 500 pounds to the square inch, of which each purchaser should convince himself before bargaining. As this pressure is several times the ordinary pressure on a steam-boiler, only the apparatus of reliable makers should be used.
As the tin plays so important a part in the construction of an apparatus, and since the purity or contamination of beverages depends so much on its purity, it is necessary for the manufacturer to get acquainted with this metal.