nature : the use of light through transparent colorless gas formed components with different refractive index liquid instructions to the device surface changes. According to a working principle of separation of liquid dollars. Common components of the transparent side of irregular trough carved Meet the glass. Level of Gas partly because of the light through the prism for reflection and silver were white, due in part to below the liquid level of liquid and glass refraction of liquid so that different parts were black, in order to direct liquid position. Various plate surface is both reflective surface of dollars.
Notice:Each item can have many explanations from different angels. If you want grasp the item comprehensively,please see below "more details data".