Magnetic Observatory, Hobart Town. 279 
the telescope, that a very tolerable mean result will be 
obtained. I have rejected several of my own observations ; 
but it was always perceptible to me at the time that they 
were likely to be rejected, from the wavy, dancing appearance 
of the atmosphere surrounding the planet, as viewed through 
the telescope. 
TV.—Lunar DISTANCES. 
The result of these observations will be communicated 
hereafter. 
V.—CHRONOMETRIC DIFFERENCE OF MERIDIANS. 
The meridian distance between the Observatory at Hobart 
Town and the following places has been measured by chro- 
nometers. 
1. Paramatta Observatory, in N.S.W. 
2. Tahlee, Port Stephen, in N.S.W. 
3. Fort Macquarie, in Sydney Harbour. 
4, Portland, Victoria. 
H. M. 8. 
Paramatta is given in the Nautical Almanac as 10° 4° 6°25 
east of Greenwich, which is Sir Thomas Brisbane's deter- 
mination.—Philos. Trans., 1829. Part ITI. 
Hf Mare Se 
Tahlee, in Port Stephen, is 10° 8 11° east of 
Greenwich, by Captain P. P. King’s independent deter- 
mination.—See Capt. P. P. King’s Astronomical Obser- 
vations, 1843-1848. 
st, We 
Fort Macquarie is 10° 4° 59°3 east of Greenwich by a 
mean of several authorities, which are given at the end of 
this paper. 
Portland was determined by an able surveyor; and an 
excellent observer, Mr. Tyers, now Commissioner of Crown 
