[17] The case of nickel may be here treated as exceptional. It is eliminated with difficulty, the nickel and copper tending to oxidise together on bessemerising. Transcriber’s Notes: Underscores “_” before and after a word or phrase indicate _italics_ in the original text. Equal signs “=” before and after a word or phrase indicate =bold= in the original text. A single underscore after a symbol indicates a subscript. Small capitals have been converted to SOLID capitals. Parentheses are used for subscripted numbers, for example 2 is represented by _{2} as in “Cu_{2}O”. Illustrations have been moved so they do not break up paragraphs. Inconsistent hyphenation has been left as printed, except “firebox” has been changed to “fire-box” in the Index to match the spelling in the main body of the book. Typographical errors have been silently corrected but other variations in spelling and punctuation remain unaltered. In some tables “Number” has been abbreviated to “No.”, “United States of America” to “U. S. A.” and trailing punctuation has been omitted to make the rows shorter. In some equations an ampersand has been used instead of “per cent.”, again in order to reduce the line length. The advertisements at the beginning of the book have been re-located to the end of the book, just before the footnote section. End of Project Gutenberg's Modern Copper Smelting, by Donald M. Levy