Testing a similar crystal, the team of scientists from Rennes University in France shows that by rotating it you can find the point where the two beams converge and that indicates the direction of the sun.

法国雷恩大学的科学家小组通过测试类似的水晶发现，转动这种水晶可以发现两个光柱的汇合点，这样就能指明太阳的方向。