534 
APPENDIX. 
placing them in charge of a suitable person for safe-keeping, until far¬ 
ther orders from the Department, or myself. 
In passing around the Cape of Good Hope, you will keep a good 
look-out for ice, as it is sometimes seen at this season. 
The enclosed notice of an island off the Cape of Good Hope, will 
claim your attention; and if possible you may pass over or near the 
spot, in order to verify or disprove its existence in that position. 
Let your stay at St. Helena be as short as possible; Horsburgh’s 
directions relative to making and anchoring at the island, are good. 
I herewith enclose you the error and rate of your chronometer, 
obtained by comparison with this ship’s standard, which has been 
performing very accurately since we left Oahu. 
Wishing you a safe and pleasant passage, and a happy meeting with 
your friends, 
I am, &c., 
Charles Wilkes, 
Commanding- Exploring Expedition. 
Lieut. Com. C. Ringgold, 
U. S. Brig Porpoise, 
P. S. You will make magnetic experiments at the island of St. 
Helena. 
Similar orders to Lieutenant-Commandant Carr of the Oregon; in a 
postscript to which, he was required to make experiments for intensity 
with Gauss’s magnetic instrument, at the island of Enxados. 
C. W. 
