soft, raised surface upon cloth, mid-14c., downy plumage, from Anglo-French pyle or Middle Dutch pijl, both from Latin pilus a hair (source of Italian pelo, Old French pel). Phonological evidence rules out transmission of the English word via Old French cognate peil, poil. Meaning nap upon cloth is from 1560s.
Updated 01/08/17. 1  of 06. Gas Furnace Types and Efficiency Ratings BanksPhotos / Getty Images The gas furnace in your home is a critically important appliance and one you depend on to work reliably, efficiently and quietly. 2  of 06. Low Efficiency Furnace: 55% to 72% AFUE (obsolete technology) Characteristics. 3  of 06.
For gas tungsten arc welding (GTAW), pure argon is more commonly used as a shielding gas. Helium/argon mixtures can be used for applications that require high heat transfer, but those applications arenât widespread. Pure helium or mixtures with a high percentage of helium sometimes are used with GTAW machines with direct current electrode negative.