Wood preservation a long-practised method and often used in today's carpentry workshops. Technological developments mean it is also possible to spray preservative over the surface of the timber. Some of the liquid is drawn into the wood as the result of capillary action before the spray runs off or evaporates, but unless puddling occurs penetration is limited and may not be suitable for long-term weathering. By using the spray method, coal-tar creosote, oil-borne solutions and water-borne salts (to some extent) can also be applied. A thorough brush or spray treatment with coal-tar creosote can add 1 to 3 years to the lifespan
Picoline its unpleasant smell. In 1849, the Scottish chemist Thomas Anderson (1819 – 1874) prepared picoline in pure form, from coal tar and via the pyrolysis of bones. Anderson also named picoline by combining the Latin words "pix" (tar) and "oleum" (oil) because coal tar oil was a source of picoline. By 1870, the German chemist Adolf von Baeyer had synthesized picoline in two ways: by the dry distillation of "acroleïnammoniak" (CH=CH-CH=N-CHOH-CH=CH) and by heating "tribromallyl" (1,2,3-tribromopropane) with ammonia in ethanol. In 1871, the English chemist and physicist James Dewar speculated that picoline was methylpyridine. If the structure of pyridine that