2 A DETERMINATION OF THE HEIGHT OF BAKN BLUFF, 



stated in the official maps of Tasmania t.o have a height 

 of 5,069 feet. This station was inside a wooden stockade, 

 now much decayed, approximately four feet in height, and 

 as the trigonometrical pole had fallen a new pine pole 5 

 feet 9 inches in height, with a white flag attached, was 

 erected on the approximate site of the station. Froin there 

 a ridge was obseirved running to Barn Bluff. About mid- 

 way between the two mountains it widened out to such 

 an extent as to- give an appearance of being a suitable 

 base to measure the difference in height of the two. The 

 remainder of the party then made their appsarance at the 

 acctiminodation house, having uiotoreij to within six miles 

 of Cradle Valley. 



The following day we visited the ridge mentioned 

 alcove, but found it to be rather too narrow to give an 

 accurate result, so determined to make a base along the 

 ridge, and then to triangulate to another point across a 

 small gully, which would give the required base. We, 

 therefore, went back to the accommodation house, and 

 next day returned and made a camp in a sheltered spot 

 approximately half-way between the two mounts. 



We first laid out a base X Y on the ridge, and 

 measured it bv a steel tape four chains in length, and 

 found to be 26.089 chains, 26.091 chains, and 26.078 chains 

 respectively. The correctnessi of the last measurement was 

 dovibted, owing to the high wind prevailing when the 

 measurement was being taken. As, however, only a 

 diflferencei in height was being ascertained, an error in the 

 length ol the base would have made a much smaller error- 

 in the height, the length of the base was adopted as 

 1.722 feet. A point Z was then fixed so that the base 

 X Z would be a suitable one to determine the distance 

 between the mo'untains, and next a flag was erected on 

 the summit of Barn Bluff. We then returned to point Z, 

 and Mr. Hutchison measured the horizontal and vertical 

 arjglesi to the points X and Y and tO' "C" (Flag on Cradle 

 Mountain) and "B' (Flag- on Barn Bluff). Owing to the 

 flag on Cradle Mountain having wrapped round the pole, 

 the point where the pole appeared above the stockade 

 was the point there measured, and on Barn Bluff the 

 ground line was found the best to adopt. 



He then took observations of the sun to determine the 

 bearing of Barn Bluff from Cradle Mountain. A good 

 site for taking observations could not be obtained, as the 

 ground wasi wet and spongy, and covered with vegetable 

 growth, but every precaution was adopted to make the 

 stand of the theodolite as firm as possible so as to minimise 

 any shifting of the instrument. Observations, however,. 



