4o6 Report S.A.A. Advancement of Science. 



360 deg. Unclamp vernier and read angle 1129 — 1128 — 1127, for 

 convenience called — , also read back vertical. The sum of each two 

 readings should be 360 deg. 



" Measure both back and fore distances with a steel tape, and 

 calculate horizontal distances. The back horizontal distance at 

 1 1 28 M should equal the fore horizontal distance previously obtained 

 at 1127 M. 



" Measure the length of the plumb bob at 11 27, distance of 

 instrument from peg at 11 28, and length of plumb bob at 11 29. 



"Subtract the rail distance (or add for Government levels) from 

 the level of survey peg, and one obtains the rail level at each peg, 

 and thus can work out the grade of track wherever required." 



(6) Sixth Method- 10 S.R.E. drive. Main Shaft. lOth May, 1898. 



1003 E to 1004 E. 



Back distance 1 5 21 Forward distance lO'SS 



Right L 200" 53' 10" Left L 159° 6' 50" 



700.^ E to 1005 E. 



Back I0'38 Forward 1015 



Right L 212^ 54' ID" Left L 147' 5' 50" 



1005 E to 1006 E. 



Back 1015 Forward 1 1 90 

 Right L 151^ 25' 30" Left L 208' 33' O" - - I' 30" 



Doubled 302' 54' o" 



Summary of Results. 



ia) Use of Instrument. In method (i) it is impossible to 



determine the use to which the instrument is placed. Checks, if 



made, are not recorded. Values of quadrants are completely at 

 variance with Government Surveyors' methods in the Colony. 



(2) A clear and concise method of shewing what is done. 



(3) The actual readings are apparently not recorded, and angles 

 are only taken out mentally. Check recorded. 



(4) Without footnote it is impossible to determine how instru- 

 ment is used. No checks of any kind are applied to eliminate 

 errors of instrument. 



