Sound: play open strings alone; play slow scales, sustaining a 20- to 30-second bow; practice everything in the lower or upper half; or watch your contact point in the mirror.
A similar process occurs on a much smaller scale to gas surrounding a single star, forming the bow-shaped arc seen near the upper left side of the Cone.
类似的过程以小得多的规模发生在锥状星云左上方的一个恒星周围，形成了一个弧形光晕。
3
Check this part for accuracy. It should have the dimensions as shown below. Unlike the upper support bow, the height of the lower bow must be maintain along with proper symmetry and width.