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.
We do not care to go into a scientific explanation of all the minute constituents or impurities of water, but it is deemed necessary to explain what is meant by the above nomenclature, as the manufacturer in the course of time might run across this term and search for information in this work.
Huminic, Geinic or Ulminic Acid are, if not identical, certainly nearly related, and by analysts only differently termed; they consist of or are found in the sediments of springs, are of a humous nature, but are not at all definite in composition. There are organic substances free of nitrogen, while there are others with nitrogen, and therein is the difference in their organic nature.
All these substances have been found or proved in spring water, and it may be certain that many other substances partake in the combination of water, but have hitherto not been found, not been searched for, or not been definitely explained.