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APPENDIX NO. X. 
No. X. 
Methods of Survey . 
It is proposed in the following sketch to give a general account of 
the methods used in surveying the coasts of Smith’s Straits, and of 
Greenland, as far south as Melville Bay. For a large portion of this 
labor I am indebted to my assistant, Mr. Sontag. 
It will be seen that the survey conducted by the returning expedi¬ 
tion has more claims to accuracy than is attainable by a mere 
running or flying survey, although the operations were limited by the 
peculiar condition of the party. 
The means employed were, of course, not new; yet a short and 
precise account of the methods used to secure as perfect a delineation 
of the shore-line as circumstances would permit may be properly given, 
with a view to a comparison of results with other surveys of the same 
region. 
It may be remarked at the outset that the geographical results of 
the expedition depend altogether for their longitude on the meridian 
of Rensselaer Harbor. The establishment of this prime meridian was 
therefore an object of great attention. 
As a general rule, the geographical positions were determined on 
shore whenever practicable; on some occasions on large floes, which 
afforded a firm basis for the artificial horizon. On several occasions, in 
Smith’s Straits, observations for latitude and longitude were made by 
means of a theodolite. This instrument was provided with a vertical 
circle of ten inches diameter, and its limb was divided to four seconds; 
attached to it was a very sensitive level, the value of a scale-division 
of which had been determined at Washington, and was found to 
equal 113". 
F ir latitude, a number of measurements of the altitude of the sun’s 
upper and lower limb were taken, commencing about twenty minutes 
before and ending twenty minutes after the culminations. An equal 
number of readings of both limbs were taken with tho instrument in 
the direct and reversed position. A screen of pasteboard protected the 
instrument from the direct action of the sun’s rays. 
Observations for time (and longitude) were taken about 9 o’clock 
a.m. or 3 o’clock p.m. 
The appareut path of the sun in these high latitudes is but slightly 
