Jan. 1830. COMPASS AFFECTED—DRAWINGS. 383 
ing to make no further use of a compass in this place; and as 
Lieutenant Skyring might have been deceived in his bearings 
from a similar cause, I hoped to procure a round of angles, with 
a theodolite set to a true bearing, which might be serviceable 
for his work, as well as my own. Many pieces of the stone, 
from different heights, were brought down ; and in most of 
them were traces of metal. 
‘“« The peaked top of this mountain is a mere heap of loose 
stones of all sizes. Whether the rock has been shattered in this 
manner by frost, by volcanic fire, or by lightning, I cannot 
tell; but I should think, from its appearance, by all three. 
Many of the stones are vitrified, and many are porous, like 
pumice-stones, although not so light. 
* 20th. I again went up Mount Skyring, taking a theodolite 
with me; and as the day was perfectly clear, and free from 
clouds, every point of land was visible, which can at any time 
be seen from that summit. Mount Sarmiento appeared in all 
its grandeur, towering above the other mountains to at least 
twice their height, and entirely covered with snow. Having set 
the theodolite to a painted post, fixed on shore near the Beagle 
(five miles distant), from which I had previously obtained the 
exact astronomical bearing of the spot on which the theodolite 
was placed; I obtained a most satisfactory round of angles, 
including most of the remarkable peaks, islands, and capes, 
within a range of forty miles from the mountain. The day was 
so fine, that it was not cold on the height, nor was there any 
wind to disturb the adjustment of the instrument. 
This business being completed, I returned on board with 
Mr. Wilson, who, during the time I was on the height, made 
some very good sketches. Even at this early period his draw- 
ings were becoming a valuable addition to the gleanings of our 
cruise, and their number increased fast; for he took much 
pains with them, and produced not only good drawings, but 
most accurate delineations of the coast. 
“* 21st. Fine weather for this climate. Mr. Murray returned 
in the whale-boat, having had a successful trip. 
*< By shooting and fishing we obtained frequent change of 
