Creosote mixed with coal-tar creosote, or fortified with pentachlorophenol. Water-gas-tar creosote is also derived from petroleum oil or shale oil, but by a different process; its distilled during the production of water gas. The tar is a by-product resulting from enrichment of water gas with gases produced by thermal decomposition of petroleum. Of the creosotes derived from oil, it is practically the only one used for wood preservation. It has the same degree of solubility as coal-tar creosote and is easy to impregnate into wood. Like standard oil-tar creosote, it has a low amount of tar acids and tar bases, and
English words of Greek origin "bacterium" < βακτήριον 'stick (diminutive)' is a kind of microorganism rather than a small stick or staff. This also applies to combining forms used in neologisms: "-cyte" or "cyto-" < κύτος 'container' means biological cells, not arbitrary containers; "-oma" < -ωμα, a generic morpheme forming deverbal nouns such as "diploma" 'a folded thing' and "glaucoma" 'greyness', comes to have the very narrow meaning of 'tumor' or 'swelling', on the model of words like "carcinoma" < καρκίνωμα. For example, "melanoma" does not come from Greek μελάνωμα 'blackness', but rather from the modern combining forms "melano-" 'dark (in biology)' + "-oma" 'tumor'.