418 APPENDIX. 
The theodolite Mr. Perry has, will be delivered to you. You will 
land, if possible, on the above reefs, and observe a full round of angles, 
together with the latitude and longitude, by equal altitudes. 
Any reefs you may meet with on your way, you will take sufficient 
angles to establish their positions. The direction of the current will 
also claim your attention, and the time of high and low water. 
Should you require the services of another officer, you will take one 
from the launch or cutter. 
You will be expected to join me at Sandalwood Bay, on or before 
the 10th instant. 
Iam, &c., 
Cuartes WILKES, 
Commanding Exploring Expedition. 
Lieutenant James ALDEN, 
U.S. Ship Vincennes. 
Xe 
U. S. Ship Vincennes, 
Savu-savu, July 3d, 1840. 
Sir 
You will, with the launch and first cutter, Mr. Knox, proceed this 
night to the harbour of Kombelau, which you will finish your survey 
of, by taking careful soundings, &c. This, it is presumed you will 
finish to-morrow. You will proceed the next day to survey the bay 
of Nandi, if you should hear nothing from me in the mean time ; and 
after completing that work, you will proceed to Passage Island, where 
you will remain a day, for the purpose of proving the observations 
heretofore made there; thence to Sandalwood Bay, by the way of the 
sunken patches of coral leading from the main reef, which you will 
carefully explore, where you will find me or orders. 
The former orders relative to your intercourse with the natives, 
must be observed strictly: they are only revoked so far as respects 
landing for the necessary observations ; and you must on no account 
omit the necessary precautions, as if you were apprehensive of an 
attack from them, viz.: that of arming yourselves well. 
The tides must be carefully observed, to ascertain the times of high 
and low water, in the way I have indicated to you, and their direction 
in ebb and flood, together with their strength by the current log. You 
will note, at the time, particularrly the trending of reefs and land in 
places. 
If the ship should be seen by you to-morrow evening off Kombelau, 
you will hoist two lights at the cutter’s masthead, anchored off the 
