Moss among three divisions: Bryophyta, Marchantiophyta and Anthocerotophyta. The current circumscription of Bryophyta includes only the mosses. The mosses, now division Bryophyta (Bryophyta sensu stricto), are divided into eight classes: Six of the eight classes contain only one or two genera each. Polytrichopsida includes 23 genera, and Bryopsida includes the majority of moss diversity with over 95% of moss species belonging to this class. The Sphagnopsida, the peat-mosses, comprise the two living genera "Ambuchanania" and "Sphagnum", as well as fossil taxa. However, the genus "Sphagnum" is a diverse, widespread, and economically important one. These large mosses form extensive acidic bogs in
Oxy-fuel welding and cutting is what chemically combines with the fuel to produce the heat for welding. This is called 'oxidation', but the more specific and more commonly used term in this context is 'combustion'. In the case of hydrogen, the product of combustion is simply water. For the other hydrocarbon fuels, water and carbon dioxide are produced. The heat is released because the molecules of the products of combustion have a lower energy state than the molecules of the fuel and oxygen. In oxy-fuel cutting, oxidation of the metal being cut (typically iron) produces nearly all of the heat required to "burn" through