444 APPENDIX. 
Your attention is particularly called to investigating any shoal, 
reef, or island that you may fall in with, not duly represented on 
your chart, taking azimuth bearings, when you have determined 
your situation. 
If you should not possess the necessary charts of the Pacific Ocean, 
you will at once make a requisition on the navy agent for that 
purpose, getting the latest and the best; I have written to him ac- 
cordingly to supply all your wants, believing that you will require 
nothing that is not necessary. 
You will, of course, continue the usual observations of tempera- 
ture, &c, and acquire as much information on your route as you can. 
In the event of the Sea-Gull not being heard from within four 
months after the 1st of June, you have permission to return to the 
United States, or join the squadron on the Pacific Station, whichever 
may suit your own views. The attempt to follow the squadron would 
be impossible, with any chance of success; therefore I do not con- 
sider myself authorized to incur the expense, and devote the time of 
any officer to so vague a prospect of service. 
Wishing you a pleasant and prosperous passage, 
I am, &c, 
Charles Wilkes, 
Commanding Exploring Expedition. 
Lieut. Com. T. T. Craven, 
Valparaiso. 
Similar instructions were given to Lieutenant-Commandant Craven 
at Callao, omitting those parts relating to Valparaiso. 
U. S. Ship Vincennes, 
Harbour of Callao, July 11th, 1839. 
Sir, 
You will avoid by all means in your power a separation ; in the 
event of such an occasion, you will steer for the island of St. Paul's, 
or its supposed locality ; thence to the island of Minerva or Clermont 
de Tonnerre, in latitude 18° 32' S., longitude 136° W. ; then hauling 
to the northward to make the Isle of Disappointment; thence by 
King George's Group, Waterlandt Land, and Dean's Island; and 
from thence to Matavai Bay in the island of Tahiti. 
You will at each of these places make some stay, and remain at 
Matavai Bay until you hear from me. 
