446 l.XI'KIHTIOX TO POINT BAKROW, ALASKA. 



fuuud afterwards tlmt so tar as the first year's magnetic work was concerned it appeared to have 

 been undertaken rather prematurely, inasmuch as it could not be supposed that differential instru- 

 ments ut' a particular description were ready at hand, nor was there suflicient time to procure them. 

 Disclaiming, therefore, such close cooperation as would have been desirable, but which was impos- 

 sible under the circumstances, the records and results herewith presented are the outcome of faith- 

 ful labor and are believed to be an acceptable contribution to our knowledge of magnetism in high 

 latitudes, and it is thought that in the second year, at least, these records will prove to be a valua- 

 ble part of the material accumulated by the several expeditions. 



Later on, in full co-operation with the work undertaken by the International Polar Commission, 

 the Coast and Geodetic Survey established at Los Angeles, Cal., a magnetic observatory and 

 equipped it with a .set of Adie's self-recording magnetometers of the Kew pattern. In the spring 

 of 1882 the adobe building had been constructed by Assistant J. S. Lawsoii, and in July following 

 the instruments were mounted and the photographic process was arranged by Mr. W. Sness, 

 mechanician Coast and Geodetic Survey. The observatory was then permanently turned over to 

 the charge of Mr. Marcus Baker, Coast and Geodetic Survey, under whose direction the absolute 

 and differential measurements have been made uninterruptedly from about the end of September, 

 1882. to the present time, and it is the intention to continue the work for some years. 



In May, 1881, Mr. J. B. Baylor, and in June following, Mr. M. Baker, of the Coast and Geodetic 1 

 Survey, were detailed to instruct at Washington Sergeants E. Israel, J. Cassidy, J. Murdoch, and 

 M. Smith, Signal Corps, U. S. Army, in the use of the sextant and the alt-azimuth for the deter- 

 mination of time, latitude, longitude, and azimuth, and in the requisite computations; they were 

 likewise instructed in the use of those magnetic instruments which they were to take with them. 

 Mr. A. C. Dark was instructed at San Francisco in astronomical observations by Subassistant J. 

 F. Pratt, Coast and Geodetic Survey. With the exception of Sergeant Israel, who proceeded to 

 Lady Franklin Bay, the above named observers formed part of the personnel of the Point Bai row- 

 party. These observers made the best use of the short time available for their instruction. 



In May, 1882, J. Palmarts and Sergeant J. E. Maxfield, Signal Corps, TJ. S. A., received instruc- 

 tions from Mr. Baker in the use of the sextant and the theodolite, and in June they practiced 

 under As.Mstant Eimbeck, Coast and Geodetic Survey, with the Brooke differential instruments, 

 which left the office for Point Barrow June 14, 1882. 



The following instructions to the parties were drawn up (June y, 1881] by the writer under 

 direction of Superintendent C. P. Patterson : 



"Instructions and notes for the guidance of the observers to Ic stationed at Point Barroic, Alaska, and 

 at Lady Franldin Bay, north of Smith Sound, Arctic Ocean. 



'As soon as the quarters of the expedition have been fixed upon a magnetic house will be 

 erected, in which the regular magnetic observations as described below will be made : other obser- 

 vations will be made when on boat or sledge trips. 



"Inistniments. For the use of the magnetic observatory there will be provided a magnet 

 ometer, for absolute and differential declination and for horizontal magnetic intensity, to be per- 

 manently mounted on a stone pier. In connection with this instrument a meridian or azimuth 

 mark will be established a short distance off the observatory and visible from it through an open- 

 ing in its wall. The astronomical bearing of this mark will be carefully determined by means of 

 an alt-azimuth instrument and solar observations. Jn the same house, but on a separate pier, will 

 be mounted a Kew dip circle, and, in the case of Point Barrow, a third instrument, a bililar mag- 

 netometer, will also be permanently mounted on its pier. At Point Barrow the magnetometer (or 

 nnifilar) and the bililar instruments will be mounted in the magnetic meridian and at a distant e 

 apart of not less than twelve feet, and the dip circle will be mounted equidistant from these instru- 

 ments, forming an equilateral triangle. At Lady Franklin Bay the two instruments will be 

 mounted in the plane of the magnetic prime vertical and not loss than 12 feet apart. Xo iron is to 

 be used in the construction of these buildings and they should not be nearer than lifty yards to 

 any other building or double that distance to any large mass of iron. Special reading lamps (of 

 copper must be provided (or use with the instruments, and they must be tested to make sure that 



