Note 522 — Chapter VIII · THE SWORD IN ANCIENT EGYPT AND IN MODERN AFRICA.
Reading edition
Quenching in oil or grease instead of water is a common practice. The workman still ‘adds to the water a thin cake of grease, or pours over it hot oil, through which the steel must pass before it enters the water, for by these means it is prevented from acquiring cracks and flaws.’ (Beckmann, loc. cit. ii. 330.)