Whilst the greatest effort has been made to ensure the quality of this text, due to the historical nature of this content, in some rare cases there may be minor issues with legibility. The pressure from the company's mains suffices for all the processes mentioned, but the furnaces may be fitted with air-blast appa ratus for producing higher temperatures. The consumption of gasper furnace in Sheffield ranges up to cubic feet per hour. Sev eral noted firms which were pioneers in gas cooking have lately given attention to the pro duction of furnaces suitable for almost every conceivablerequirement of the metal trades.