SIR: You will proceed at once to San Francisco, California, and thence by steamer or by rail and steamer to Sitka, Alaska. It is expected that you will join Mr. I. C. Russell, Geologist, at Victoria, B. C., or at Sitka; and you will report to him for further orders. Very respectfully, G. K. GILBERT, _Chief Geologist_. _Approved_, J. W. POWELL, _Director_. * * * * * {194} _Washington, D. C., May 29, 1890_. Mr. MARK B. KERR, _Topographer_. SIR: You are hereby assigned to field-work in the vicinity of Mount St. Elias, Alaska, in the party under charge of Mr. I. C. Russell. Upon the receipt of these instructions you will please proceed without delay to the field, and map upon a scale of four miles to an inch such territory in the vicinity of Mount St. Elias, including that mountain, as the field season will permit. The work should, if practicable, be controlled by triangulation. Special attention in the course of your work should be given to measuring the altitude of Mount St. Elias, and it should be determined by triangulation and also, if practicable, by barometer in such manner as to be conclusive. The topographic work should be controlled by triangulation. As many positions on this coast are approximately known, including a number of the prominent peaks, astronomical determinations of position will not be necessary unless needed to supplement the triangulation. The details of your outfitting and the management of the work will be left to your own judgment. Very respectfully, HENRY GANNETT, _Chief Topographer_. * * * * * _NATIONAL GEOGRAPHIC SOCIETY_. _Memorandum of Instructions to the Party sent out under the Direction of Mr. I. C. Russell, assisted by Mr. Mark B. Kerr, to explore the Mount St. Elias Region, Alaska, 1890_. The general object of the expedition is to make a geographic reconnoissance of as large an area as practicable in the St. Elias range, Alaska, including a study of its glacial phenomena, the preparation of a map of the region explored, and the measurement of the height of Mount St. Elias and other neighboring mountains. Observations should also be made and information collected on other subjects of general scientific interest as far as practicable. The purpose of these instructions is mainly to suggest the lines of investigation that give promise of valuable results, but it is not intended that they shall limit the director of the expedition in the exercise of his own discretion. GARDINER G. HUBBARD, _Chairman_, MARCUS BAKER, WILLARD D. JOHNSON, _Committee_. _Washington, D. C., May 29, 1890_. {195} APPENDIX B. REPORT ON TOPOGRAPHIC WORK. BY MARK B. KERR.