Hi I'm studying strain analysis using Mohr's circle. I have some problem using a star rosette to construct the circle. My problem lies with trying to identify the points which indicate the planes the rosette act on. Besides that, what is meant by "strain rosette with gauge X (gauge X being one of the gauges of the delta rosette) acting along a principal direction"? Sorry, no equations to show as Mohr's circle is really based on graphs. Any help is appreciated.