50 Report of the U. 8S. Coast Survey for 1883. 
tinez Enst, was determined by spirit leveling to be 1116-09 
meters (3661 ‘7 feet). This difference of level was also further 
determined from hourly readings of the barometer for about 40 
days, and also from hourly seigrrmentane of reciprocal zenith 
distances during the same time, whenever the weather permit- 
ted. The results by the three rabedes are compared and some 
general principles deduc 
ed. i 
e 13th moves also prepared by Mr. Schott, we have — 
the first. general account, with results from magnetic observa- 
tions, of the U. S. International Polar Station at Ooglaamie 
near Point Barrow, Alaska. r. Schott makes very clear at 
the outset, the nature and extent of the codperation which the 
survey was able to give. This codperation related solely to 
terrestrial magnetism, and this appendix is entirely devoted toa 
discussion of the results obtained. Owing to the want of 
trained observers and the necessary instruments, sion pro-. 
duction requires time, the ee i first year was ‘ incl- 
dental” rather than complete. e second year additional 
instruments and an addict observer saedares the codpera- 
tion much more complete and satisfactory. 
Regular magnetic observations began December 1, 1881, and ; 
continued hourly, with two se interruptions, till ‘August 27, 
1883, giving a series of about 21 months. The pt seta et : 
during the year 1881-2 sacs of hourly observations of t 
declinometer sha dip circle (with needle weighted), and the 
term day observations. ede the year 1882-3, differential 
magnetometers were in placé and gave hourly readings of de- 
bso 
clination, horizontal ran ae vertical force. The absolute 
measures of the elements were continued through this second 
year. 
The estimate of Mr. Schott, who has gone over these records — 
with laborious fidelity is that the ‘records and results here- 
with presented are the outcome of faithful labor, and are believed to 
be an acceptable contribution to our knowledge of magnetism in — 
high ese a and it is thought that in the second year, at least, 
these will prove to be a valuable part of the mater ee _ ; 
sia : bapa several expeditions.” We hasten to add t 
that Mr. Schott’s experience, skill and diligence in the re : 
sion ie magnetic observations are shown by the long series of - 
papers on this subject from his pen during the past thirty — 
years, yt if, therefore, he has sueceeded in extracting a “con- — 
tribution to our knowledge” from a series of observations pa | 
reveal serious self. contradictions, important omissions 
defects which nothing but patient ingenuity and skill can har : 
monize. even roughly, he deserves our hearty thanks. Noo 
experienced in the study of terrestrial magnetism is ignorant of 
the fact that his own earlier observations were poor, - and 
