APPENDIX, 403 
ascertained with regard to the main points in sight; and all entrances 
or passages through the great reef to the northward, must not escape 
your attention: none it is believed occur, until you reach Ragi-ragi, 
on the east side of the Malaki Islands. At these islands, the ship- 
channel is supposed to go between them and the main island. You 
will observe particularly if the main northern reef joins these islands. 
Ascertain their size, and get an azimuth on the high hill of Ovolau if 
possible; here it is extremely desirable to obtain accurately the lati- 
tude and longitude. Chronometers are furnished both beats, whose 
rates and errors are given. After passing these, you will continue on 
to Taboa, when you will find another passage through the reef to the 
northward; this will be examined, as that off Ragi-ragi, getting the 
trending of the outside reef both east and west by careful bearings at 
both places. Thence you will proceed through the aforesaid ship- 
channel, along the island of Vitilevu, down as far as Ba, where you 
will find the ship Leonidas, Captain Eagleston, who no doubt will be 
happy to supply any thing you may be in want of, for which he will 
receive remuneration. You will make no unnecessary delay here, but 
continue on your survey as far as the island of Malolo, off the western 
end of Vitilevu, where you will meet further orders from me in ten 
days; if, however, this should not occur, you will return. On your 
way back, following the outside reef on its inner edge (which J believe 
does not exist beyond fifteen miles from the land), and taking observa- 
tions so as to establish its various points by bearings and latitude and 
longitude, and regain this anchorage as soon as possible. A patent log 
is furnished you for measuring your distances run, and an azimuth 
compass. 
You will observe the variation, and not omit your latitude daily by 
meridian observation or double altitudes, and also sights for your 
chronometers, morning and evening; taking comparisons daily be- 
tween them, which will be inserted in your note-books. 
You will make a rough diagram as you proceed, on a large scale, 
which you will have in readiness to send me by any opportunity that 
may occur. 
Each boat will keep a log of her proceedings. 
You will always keep the boats within signal distance of each other, 
separating them in cases of extreme necessity only, for a short time. 
You will communicate these instructions to Mr. Knox. 
lam, &c., 
Cuartes Witkes, 
Commanding Exploring Expedition. 
Lieutenant James Aprn, 
U.S. Ship Vincennes. 
