The American Journal of ScienceJ.D. & E.S. Dana, 1915 - Science |
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Al,O angle anorthite anorthosite appears Arroyo Mocho axis binary system bone boundary curve cent chemical chloride clinoenstatite components composition compound cooling Creek cristobalite crystallization curve delta deposits described determined diabase diagram diameter disks equilibrium Escarpment ester etching ethyl hydracrylate eutectic facet fauna feet feldspars field figures forsterite fossil Geol Geological given glaucophane grains gram granite harlani heating hydracrylic acid hydrochloric acid inches indicated lake lawsonite liquid material melting point melting temperatures method minerals mixtures molar morainic Mylodon neural observed obtained olivine optical oxide Paramylodon plane plates portion present pressure primary phase pyroxene quartz quintuple point radiation reaction Refractive indices region represented robustus rocks Sams Valley sand Schoharie Schoharie Creek schreibersite separated shows side silica sodium solid phases solution species specimens spinel stream surface TABLE ternary system tion trapezohedral triangle tridymite twin valley vapor
Popular passages
Page 14 - As the components of a system there are to be chosen the smallest number of independently variable constituents by means of which the composition of each phase participating in the state of equilibrium can be expressed in the form of a chemical equation.
Page 326 - ESTABLISHED BY BENJAMIN SILLIMAN IN 1818. The Leading Scientific Journal in the United States Devoted to the Physical and Natural Sciences, with special reference to Physics and Chemistry on the one hand, and to Geology and Mineralogy on the other.
Page 326 - Professor JOSEPH S. AMES, of Baltimore; Mr. JS DILLER, of Washington. Two volumes annually, in MONTHLY NUMBERS of about 80 pages each. This Journal ended its first series of 50 volumes as a quarterly in 1845 ; its second series of 50 volumes as a two-monthly in 1870; its third series as a, monthly ended December, 1895. A FOURTH SERIES commenced in January, 1896.
Page 14 - The number of degrees of freedom of a system is the number of data which must be given in order completely to determine its position.
Page 14 - We shall therefore define the number of degrees of freedom of a system as the number of the variable factors, temperature, pressure, and concentration of the components, which must be arbitrarily fixed in order that the condition of the system may be perfectly defined.
Page 14 - Findlay ('04, pp. 8-18) will assist in gaining some of the general ideas involved in this subject: A heterogenous system is made up of different portions, each in itself homogeneous, but marked off in space and separated from the other portions by bounding surfaces. These homogeneous, physically distinct and mechanically separable portions are called phases.
Page 211 - Bumelia with about a score of species is confined to America in the existing flora, ranging from the southern United States through the West Indies and Central America to Brazil. It has numerous fossil species, the oldest coming from the Upper Cretaceous (Dakota sandstone) of the western interior. In addition to the six Wilcox species, which are prototypes of still existing forms, there are two Eocene species (Ypresian) in southern England. There are about a dozen Oligocene species, ten of which...
Page 14 - C + 2 — P where P denotes the number of the phases, F the degrees of freedom, and C the number of components. From the second form of the equation it can be readily seen that the greater the number of. the phases, the fewer are the degrees of freedom. With increase in the number of phases, therefore, the condition of the system becomes more and more defined, or less and less variable.
Page 66 - A12O« and MgO always consists of three solid phases whose fields are adjacent. The same three solid phases will be the final product of crystallization from any solution whose composition lies within the triangle formed by lines joining the compositions of these three phases. These composition lines which have been drawn in Fig. 7 divide the diagram into 6 triangular areas. Each of these triangles represents all possible mixtures of those three compounds whose compositions are represented by the...
Page 121 - Your committee finds as follows as to the facts: I. Prior to the hostilities domestic chemical industry was utilizing and exploiting every reasonable opportunity to its full extent. II. Since the outbreak of hostilities domestic industry has increased its output just as fast as physical means could be provided and physical obstacles overcome. III. Since the outbreak of hostilities domestic plants that had theretofore been shut down or partly dismantles because of disastrous foreign competition are...