See how for an area coverd by three stations, the station are marked and bearings are measured so that triangulation can be marked with respect to these three lines AB, BC and CA.
One cannot overstate the importance of taking the back bearing. My experience with compass work, decades ago, showed me how many times there appeared a "local attraction" which pulls the needle away from the proper heading. If one excludes the back bearing they become unaware of how far off they have become on the line to be surveyed. In the early 1980's I would use a compass to "rough traverse" the survey for new underground gas lines. We would use aerial photo's to map the proposed route, then place "targets" at road crossings and intersections to "reinforce" the course. I would go out with my compass and flag a line between these targets. Sometimes I was pretty close, most times I would have to back track and correct my error. Then the survey crew would come through with total stations and run the "true line". Now GPS has changed all of that, but it was a fun exercise and a real eye opener on the limitations of compass accuracy. Later I would have the crews rough tape the surveyed line, after it had been cleared to get from one reference point to the next. This to was a good exercise as the crews got a "real" lesson of how inaccurate many of the original surveys were. When we did boundary work this lesson helped them to understand that one had to look in a bigger circle than a layman might of expected to find the called for corner. As technology has progressed the accuracy of surveying has greatly multiplied. Accurate geospatial location is the basis for civil progress in land development. Many countries are way behind on the importance of this, as a result conflicts with roads, drainage, utilities, and buildings occur simply because there is no information base to prevent it. Governments would be advised to use GPS to place suitable controls so that private firms, even using a compass and tape could survey and plan for infrastructure that works together. Great video guys, how about one where you head out of the park!
Agree with Bell sir Yes from each station Back bearing needs to be taken first then the Fore bearing, always.... Also then from initial station the bearing observed.....
