The intention in making this translation was two-fold; firstly, to school myself in the matter of ore-deposition; and secondly, to place before British mining engineers and geologists an important work upon this subject, in a language with which, upon the whole, they would be better acquainted than with the original German. In the first part of this intention I feel I have succeeded. With regard to the second I trust that the realization will not fall too far short. I have endeavoured faithfully to bring out both the fact and the spirit of the author's work, this being of such high standard that the reception of a translation must depend largely upon the degree of closeness with which the original is approached.