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 filter, manufactured by The Baker Water Filter and Purifying Co., New York, is made of bronze, tinned or nickel plated, and divided in two halves, bolted together. The medium is "Baker's Filter Compound," consisting essentially of magnesia and animal charcoal, combined to form a plastic, porous mass in blocks or sheets at any desired thickness, and can be used in connection with any filter. This filtering compound is surrounded by fibrous asbestos to arrest the coarse impurities of the water. All the filtering material is secured by perforated plates. This filtering compound acts mechanically and chemically very well, but where any amount of work is to be done and hydrant water is filtered through, it should be renewed almost daily; where ordinary well or spring-water is used, it may last longer.
Fig. 20. - Baker's Pressure Filter.