Acetylene of 180°. Acetylene was discovered in 1836 by Edmund Davy, who identified it as a "new carburet of hydrogen". It was rediscovered in 1860 by French chemist Marcellin Berthelot, who coined the name "acétylène". Berthelot's empirical formula for acetylene (CH), as well as the alternative name "quadricarbure d'hydrogène" ("hydrogen quadricarbide"), were incorrect because chemists at that time used the wrong atomic mass for carbon (6 instead of 12). Berthelot was able to prepare this gas by passing vapours of organic compounds (methanol, ethanol, etc.) through a red-hot tube and collecting the effluent. He also found that acetylene was formed by
Acetylene and advantages of arc-based welding processes have made oxy-fuel welding nearly extinct for many applications. Acetylene usage for welding has dropped significantly. On the other hand, oxy-acetylene welding "equipment" is quite versatile – not only because the torch is preferred for some sorts of iron or steel welding (as in certain artistic applications), but also because it lends itself easily to brazing, braze-welding, metal heating (for annealing or tempering, bending or forming), the loosening of corroded nuts and bolts, and other applications. Bell Canada cable-repair technicians still use portable acetylene-fuelled torch kits as a soldering tool for sealing lead sleeve