 So for this video, we're going to talk briefly about how to do a next step in the Thiesan polygon method. After step one, we've created a delone triangulation of our data set. And now what we're going to do is the next step of the delone triangulation, which is to divide each of these segments or bisect each segment in the triangulation. Now for each piece, each segment here in this triangulation we're actually interested in the position halfway between each segment. What we're going to sort of consider here is this idea that if 4.66 and 6.01 are two different, we'll say that they're little homesteads and they're making claim on the land in between them, if they were going to divide a line, create a line in between them, there would be a line to be halfway between the distance between the two of them and anything on one side of the line would be essentially claimed by the 4.66 and anything on the other half of the line would be claimed by the 6.01. So in order to do that, we're going to go ahead and measure each line and bisect the line. Now one way to do this is to use a ruler and actually do the measurement. For example, between this 4.66 and the 6.01, I can look carefully, line up the edges of my rulers best I can, and if I read carefully, I see a value of approximately 7.4 centimeters. 7.4 centimeters divided by 2 is 3.7, so I can move along the line here to 3.7 centimeters and I'm going to make a mark bisecting that particular point. And there's a mark halfway down that line. I can do a similar process with each of the parts here, going from 4.66 to 3.86. Again, I'm not concerned with the values 4.6 and 3.86. I'm only concerned of the distance in between them. If I look carefully in attempt to read that, I see it's 10.8. Half of 10.8 is 5.4, so I will go ahead and make a mark at that point bisecting the particular line. Now, you might recall from your geometry class a method of creating a bisector, a perpendicular bisector, using a compass. If I choose to use a compass, I can do so. This actually creates a fairly accurate and fairly quick method of doing so. What I can do is I find a place. In this case, my compass is not particularly large, so I'm going to use it on a smaller one of my segments. But what I can do is I open the compass so it's at least half of the distance. I estimate what half is, and I open the compass so it's at least half of that distance. And I create an arc. Now, I maintain that exact same size of that arc and place the point of the compass at the other end of the segment. And I create a second arc. Now, for that particular arc, you'll notice there are two intersection points for these two arcs that I created. And we know that both of those intersection points are the same distances away from the ends of the segment. Well, if I take those two lines, those two points, the point here where they connect and the point there where they connect and sketch and connect them, that connection point will run through, this line is called the perpendicular bisector, and that will run through the middle of the segment. So that's another way that we can find the middle of the segment and we don't have to do it with measurement and with the calculations from the measurement. Not necessarily an easier way to do it, but it is a way to use tools and perhaps a little bit more accurate. The other value of this is this is going to go ahead and create a perpendicular bisector for you, drawing a little bit of the perpendicular line. And we will want to be able to use the perpendicular extension of each line as we move forward. In fact, if we don't use a perpendicular bisector, what we will want to do for each of these bisection pieces is to go to each line, use the corner of a piece of paper, something else that we know is perpendicular, and extend those lines just a little bit so that each of them is perpendicular to the segment. So your next task to complete the thesis in polygon or the next step is to go ahead and triangulate or find the perpendicular. So your next step in calculating the thesis in polygon is going to be to find perpendicular bisectors for each of the segments and to sketch them in.