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 is made of heavy metal thoroughly tinned. Its centre of body is filled with sponge of a high grade compressed into about one-quarter of its original size. Below this sponge is a perforated metal plate. Water passing through this filter leaves all suspended impurities behind it, and for this purpose it will serve very well.
However, water holding organic or inorganic impurities in solution should be treated as directed in this Chapter.
The sponge in this filter must be cleansed frequently and renewed occasionally, but this can be done with ease.
Fig. 22. - Puffer's Sponge Filter.