History of Chemistry in Ancient and Medieval India, Incorporating the History of Hindu Chemistry by Acharya Prafulla Chandra Ray c15.s2.35

c15.s2.35

Absence of manganese is significant. Low percentage of sulphur indicates the use of charcoal as fuel, as also the purity of the ore. The pillar has wonderfully withstood the influence of rain and air for over fifteen centuries without giving any sign of rust formation. It has been suggested that possibly high phosphorus and low sulphur and manganese content has contributed somehow to its strikingly high corrosion resistance. There might be some truth in it, for in the absence of a second metal the possibility of the formation of galvanic couple is not realized, which constitutes one of the most fundamental conditions for rusting to occur. Or, there might be a thin protective film of magnetic oxide (Fe₃O₄), produced on the surface of the pillar by treatment like heating and quenching after being painted with a mixture of different salts and organic substances. There are evidences of iron being subjected to such treatment for improvement of their quality in some of the ancient alchemical treatises. Expert observers of all classes are of opinion that this pillar presents an indisputable and permanent record of marvellous metallurgical skill and engineering ability of the ancient Indian workers, which can reasonably claim unstinted admiration even of our present time. According to the opinion of the experts the pillar was constructed by welding short pieces of wrought iron previously forged into shapes. The Committee of the Iron and Steel Institute in 1872, which made special enquiries with regard to this pillar, came to the conclusion that iron blooms of about 80 lbs. weight each, produced in a primitive blast This page appears to be entirely blank, with no visible text, headings, figures, or page furniture to transcribe.