This work is intended primarily as a text-book for a year's work in the study of minerals and rocks. While full enough for class work it is condensed enough for field work. There is decided advantage in using the same book in the field as in the class room and laboratory.<br><br>Part II contains the description of 175 minerals. These have been selected with great care, although the list is necessarily an arbitrary one based upon the author's experience and judgment. These include all the common minerals and most of those of any special economic, geological, or scientific importance. Some of the minerals are comparatively rare but are selected so as to give a comprehensive view of the mineral kingdom as a whole.<br><br>About a third of the more common and important of the minerals are distinguished by larger type than the others. These fifty-six minerals include all the very common minerals taken the world over. In a short course in mineralogy attention may be confined exclusively to the shorter list and in that case other portions of the book also would have to be disregarded.<br><br>The section dealing with the chemical properties of minerals has been placed first because in elementary work it is of prime importance. A qualitative scheme, especially applicable to minerals in that calcium phosphate, fluorid, and borate are provided for, has been included.<br><br>In geometrical crystallography, symmetry has been emphasized and the idea of hemihedrism is abandoned. A tabulation of the thirty-two crystal classes is given but only eleven of the thirty-two classes are described in detail. From one to four common minerals of each class are used as illustrations.