But if we collect it very gently, and we bring it up into the lab and just squeeze it at the base of the stock, it produces this light that propagates from stem to the plume, changing color as it goes, from green to blue.
Però si l'agafem molt cuidadosament i la pujem al laboratori i apretem una mica la base de la soca, produeix aquesta llum que es propaga des de la tija fins les plomes, canviant de color mentre es mou, de verd cap a blau.