Use a Compass to Determine the Width of a Stream
More Articles Related to CompassYour compass is a measuring tool that can be adapted to a variety of needs. As shown here, it can be used to measure more than just direction.
You can use your magnetic compass to determine the width of a stream or small body of water without having to get wet. This quick and easy method of determining distance using a compass may just come in handy. In any case, it is always a good trick you can use to amaze your fellow survivors.
Here is how it is done.
- Standing at the edge of the water, sight an object directly across from you on the far bank. Take a compass reading on this object and mark the spot where you are standing.
- Walk along the stream until the compass reading to the same object across the stream changes by 45-degrees and mark this spot also.
- Now measure the distance between the two marks you set. This will be equal to the distance between the first mark and the object you sighted across the stream.
For example:
Say you are standing next to a stream and directly across from you on the opposite bank is a large tree. Take out your compass and sight the tree. Let’s pretend the compass reads 300-degrees (Azimuth type compass) or S30W (Quadrant type compass). Mark this spot and then walk either downstream or upstream until the compass sighting on the same tree reads 45-degrees in either direction from your first reading (either 255-degrees or 345-degrees on an azimuth type compass, S15E or N15W on a quadrant type compass). Mark this position also. The width of the stream is equal to the distance between your two marks on the ground. If you have practiced pacing (and every survivor should) you can count the number of paces between the two marks and calculate the width of the stream.
You can click on the thumbnail picture above for a larger image showing just how the compass method of determining distance works.
The best survivalists are skilled in using whatever materials at hand in novel ways that give him an edge over his environment. "Thinking out of the box" is a trademark of the true survivor.
Florida, U.S.
I think that your conclusion that the distance from point 1 to point 2 on the bank is equidistant to the distance from point 1 to the mark on the other bank is incorrect. The formula for solving the hypotenuse of a right triangle is a squared plus b squared equals c squared. A simpler version is a ratio of 3-4-5 for sides a, b and c. Therefore the distance between point 1 and 2 would be different from that from point 1 to the opposite bank.
Survival Topics: Dennis, this would be true is we did not force the size of the angle formed between the stream bank at position 2 and fixed object across the stream. In this case we have made the angle 45°. Since the opposite angle therefore must also be 45° (45° + 45° + 90° = 180°) then both sides of this right triangle must be equal in length.
WA, USA
And math proves useful again. I always liked geometry when I was in school because I knew it had many practical applications in the real world (as you illustrated here). Thanks for sharing this.
You are welcome to share this Survival Topic with others. I only request that you use a short blurb (not the entire survival content) and this code to
link to the origional:
Struer, Denmark
Thank you very much for showing me how to use a compass to find the width of stream.