200 
PROCEEDINGS OF SECTION A. 
by triangulation from Melbourne. "We are thus enabled to assign the 
most probable value to the longitude of the south end of the marked 
boundary, viz. : — 
Longitude of Melbourne Observatory — (xiv.) 
9h. 39m. 54 sec. 04=144° 58' 30"*G0 
Interval Mount Buskin A — Melbourne 
Observatory (by triangulation) ... 4 00 37 *46 
Longitude of Mount Buskin A ... ... 140 57 53 *14 
Pile No. 3 on Boundary Line 301 feet S. 
48° 10' E. of Mount Buskin A ... 2 *84 
Longitude of Pile No. 3 on marked boundary 
between South Australia and Victoria 140° 57' 55"‘98 
= 9h. 23m. 51s. 73 (xv.) 
This shows that the southern end of the marked boundary 
between South Australia and Victoria is 2' 04" 02=9,921 feet =150 
chains 32 links west of the 141st meridian of east longitude from 
Greenwich. 
1 may point out that in the plan showing the survey of the lower 
part of the Glenelg, issued by the Crown Lands Department of 
Victoria in November, 1874, the distance of the boundary near Mount 
Buskin from the 141st meridian is given as 136 chains 63 links, or 
13 chains 69 links less than the value deduced here. 
BOUNDARY LINE BETWEEN SOUTH AUSTRALIA AND NEW SOUTH 
WALES. 
In 186S Mr. (now Sir Charles) Todd, co-operating with the 
Government Astronomers of Victoria and New South Wales, deter- 
mined telegraphically through the Melbourne and Sydney Observa- 
tories the longitude of a point (to be referred to in these pages as the 
“ Boundary Pier”), situated in latitude 33° 55' 8" S. and 25 chains 
68 links W. of the north end of the marked boundary between South 
Australia and Victoria, for the purpose of deducing a more accurate 
position of the 141st meridian, which was to be adopted as the 
common boundary of South Australia and New South Wales. At the 
point in question Mr. Todd mounted a 4-feet transit instrument, and 
connected his temporary observatory with the telegraph line, which 
was about one-third of a mile away. He observed transits of 
previously selected stars on the nights of May 9, 10, 13, and 14, the 
first two being devoted to the interval Sydney-Boundary, and the 
others to the interval Melbomrne-Boundary. The observed times of 
transit of each star over the nine wires of his telescope were trans- 
mitted by corresponding galvanic signals, made by hand with the 
ordinary observing key, and automatically recorded on the chrono- 
graph of the receiving observatory, where the same stars were observed 
at meridian passage, and the corresponding times recorded on the 
same chronograph. 
These operations gave the following results, viz. : — 
h. m. Bee. 
Interval, Sydney to Boundary Pier ... 0 40 59*718 (A 1 ) 
„ Melbourne to Boundary Pier 0 16 03*767 (B 1 ) 
Melbourne-Sydney (indirect) 0 24 55*951 (C 1 ) 
