History of Chemistry in Ancient and Medieval India, Incorporating the History of Hindu Chemistry by Acharya Prafulla Chandra Ray c37.28

c37.28

The composition is, therefore, very similar to that of the iron of the Delhi Pillar. But while the iron pillar at Delhi, as reported before (*vide*, p. 100), shows immunity to rusting even after centuries, the iron beams of the Konarak temple are more or less severely corroded. This seems to suggest that the moist and salt-laden air of the Orissan sea coast possibly provides a more favourable condition for corrosive action. This has been corroborated by the recent work of J. C. Hudson† of British Iron and Steel Research Association, who investigated the causes responsible for the remarkable resistance to corrosion shown by the Delhi Pillar, which has long been a subject of great scientific interest. Hudson has shown that the relative humidity of the air at Delhi seldom exceeds 70 per cent, which, according to the classical researches of W. H J. Vernon, serves as the critical limit for the atmospheric corrosion of iron and steel to set in. This should, therefore, lay to rest all speculations, and eliminate all hypothesis, regarding the alleged intrinsic superiority of the iron of Delhi Pillar, so far as its corrosion resistance is concerned.