Dumpy Level Distance Measurement, Dumpy Level Rise and Fall Graphing

Today we started off by taking the dumpy levels out and measuring several different points around the entire perimeter of the Tafe college. Each point was roughly 60 metres away from the previous point. In all there were around 17 different points. To measure each point we set up the dumpy level inbetween two points and sighted the datum point, which was to be our neutral level, also written as 10 000.
We then kept the dumpy level, on the same point and simply turned the dumpy level around roughly 180 degrees to face the next point. We measured the next point on the staff as well. Once we had measured the first point, after the datum, we moved the entire level and tri pod, and set it up inbetween the next two points (marked on the ground). So we had the level set up around 30 metres from the last point and 30 metres away from the next point.
By amounting 34 different measurements, we then began to work out how much difference was between each set of two measurements, so the height of the point in front of the tripod minus the height of the point behind the tripod.
After we had completed this we then moved on to graphing our figures and our work can be seen on the graphs Greg, Mike and I have. We chose to graph the rise and fall of the terrain based around the 10 000 scheme, so first off we had two measurements that when equated came up with -860, so we did 10 000 - 860, which equalled 9 140. So we marked a dot on the graph at 10 000 and then one at 9 140, and joined them together. We repeated this process using a calculator and came up with a line graph that showed the change in height of the terrain.

We also showed on our graph how far away each point was away from the datum point, and came up with a heighest point being around 2.5 metres above the datum point.

After this we learnt how to estimate quite accurately how far away the staff was from the dumpy level by only using the dumpy level. All you have to do is sight what height the top stadia is at and then subtract the bottom stadia height. Once you have this then you multiply it by ten and it will give you a rather accurate measurement of how far away the staff is from the dumpy level.