384 APPENDIX. 



some and useless, are not to be lost sight of, but are to be picked up 

 for examination. 



Every opportunity of trying the current must be taken advantage of, 

 and marked. 



Astronomical observations, viz., lunar distances of the stars, east, 

 and west of the moon, of the sun, and of the planets, to be frequently 

 taken. 



Observations for chronometers must be taken daily, mornings and 

 afternoons, when the weather will permit ; azimuths and amplitudes, 

 at least once or twice a day, in the morning, or in the afternoon, and 

 the ship's head noted at the same time. 



Any of the officers (among whom are considered the scientific 

 gentlemen) will on all occasions promote the objects of the Expedition 

 by procuring any article referred to in the foregoing instructions, or 

 aiding in carrying into effect the same. And the officer of the deck 

 is authorized to stop the ship's way, and perform any evolution with a 

 view of carrying into effect the above, in which case he will report 

 the same immediately to me, if time does not permit his doing so 

 previously. 



It is necessary for the sea-officers to make themselves thoroughly 

 acquainted with the heavenly constellations, in order to be efficient in 

 noting the course of meteors, &c. 



Charles Wilkes, 

 Commanding Exploring Expedition 



U. S. Ship Vincennes, 



At Sea, August 25th, 1838. 



XL 



U. S. Ship Vincennes, 



At Sea, August 25th, 1838. 



The undersigned, commanding the Exploring Expedition, in com- 

 municating the following instructions, from the Navy Department, for 

 the government and information of those under his command, directs 

 the particular attention of all persons in the Expedition to the same, 

 and especially to that part of them, which prohibits any one furnishing 

 to persons not attached to the Exploring Expedition, any commu- 

 nications which have reference to the objects or proceedings of the 

 Expedition. 



" Although the primary object of the Expedition is the promotion of 

 the great interests of commerce and navigation, yet you will take all 

 occasions, not incompatible with the great purpose of your under- 

 taking, to extend the bounds of science, and promote the acquisition 

 of knowledge. For the more successful attainment of this, a corps of 



