MAGNETIC SURVEY OF TASMANIA. 85 
Besides the chronometer, the astronomical instruments 
were an Everest theodolite, a sextant, and an artificial 
horizon. 
- From examination of the amount of inconsistency in re 
peated observations, and a careful examination of the scales 
of ihe instruments, it appears probable that the. accuracy of 
the astronomical work is of a slightly higher order than that 
which can be attained with the Kew magnetic instruments. 
It is probable that the deduced positions and azimuths are 
seldom in error by as much as 30/', and never by as much as 
60'’. But it is best to Jeave a record such that all the 
strictly astronomical work can be retested, and the accuracy 
of relative azimuths, according to our observations, may be 
tested with better instruments than were used in the present 
survey. For this purpose it will be necessary to pick up the 
M.S. marks, and re-cbserve all the terrestrial objects. 
In view of these necessities of the future, the information 
given below for each siation will be seen to be of permanent 
importance. 
The picking up of the M.S. marks, even when buried, will 
probably prove easy, with the help of (1) a prismatic com- 
pass, (2) a sextant, (3) a fine steel probe to feel for the mark, 
(4) a measuring-tape. 
No corrections have been made for diurnal variations, &e., 
as it has been thought that, when in the future the observa- 
tions are repeated, there will probably be better means of 
making such corrections. 
In the details given for each station below the azimuths 
are true, and are in all cases reckoned from the south point 
in the direction S.W.N.E. The various terrestrial objects 
observed at each station are partly denoted by capital letters 
and partly by small letters, the former being of the general 
nature of distant permanent marks, and the latter of near 
sub-permanent ones, 
Such an entry as for Scamander below :— 
“Magnetic station from M.S. mark.—Distance, 79 cos 10° 
3’ feet,” implies that the measured slant distance was 79 
feet, and the angle of elevation or depression was 10° 3’. 
This sometimes is not the dip of the ground, but that from 
the theodolite telescope to the peg marking the magnetic 
station. 
We desire to place on record our thanks to the Govern 
ment of the State of Tasmania for the enabling grant of 
£150 made to us; to the State Treasurer, the Hon: Stafford 
Bird, for the telegraphic facilities afforded to us; 
to Mr. H. C. Kingsmill, Government Astronomer, 
