Ixviii Instruction to Scientific Observer's, S^c, 



INSTRUCTIONS FURNISHED TO SCIENTIFIC OBSERVERS 

 ATTACHED TO THE VICTORIAN EXPLORING EX- 

 PEDITION—SURVEYOR, ASTRONOMER, METEOR- 

 OLOGIST, GEOLOGIST, MINERALOGIST, ZOOLOGIST, 

 AND BOTANIST. 



INSTRUCTIONS FOR THE SURVEYOR, ASTRONOMICAL' AND METEOR- 

 OLOGICAL OBSERVER. 



1. Every opportunity sliould be taken to ascertain the geographical 

 position of the party, referring it to some well marked point, as 

 offered by an easily recognizable mountain, the junction of rivers, 

 creeks, &c., &c. 



2. This should be done by astronomical observations, as well as 

 by dead reckoning. 



The dead reckoning always to commence with the last good, reliable 

 astronomical observations made. 



3. For determining the Latitude, the different methods to be 

 chosen depend entirely upon circumstances, and it is only mentioned 

 here that observations on sun, moon, and stars will have to be used. 



4. The determination of the Longitude should be effected by lunar 

 distances ; if with stars, eastern and western distances should inva- 

 riably be taken when possible, and the longitude should be derived 

 from both sets. These observations, as well as those on latitude, 

 should always be reduced immediately after the observations, or at 

 least as soon after as possible. The longitude should further be 

 ascertained whenever an opportunity occurs by occultation of stars, 

 by eclipses of the sun, moon, and Jupiter's satellites. There is no 

 necessity, however, for reducing these observations while on the 

 journey, as it would be impossible to devote that amount of care to 

 this work without interfering with the more essential work, and 

 which would be desirable; and the original observations should, 

 as early as possible, be clearly copied with ink, in a book, with every 

 fact necessary for the subsequent reduction. 



5. All astronomical phenomena of particular interest should be 

 observed, if the means at the disposal of the astronomer do admit 

 of such observation, and if these should not interfere with the ge- 

 neral progress of the Expedition. 



6. The variations of the Compass must be observed as often as 

 circumstances permit. 



