辐射和传导性。凫毛被用来制作凫绒,因为它们能保留大量的空气,防止对流。1925年的匿名插图。私人收藏。(Radiation and conductibility: Eider feathers are used to make eiderdowns because they retain a large amount of air and prevent convection. Anonymous illustration from 1925. Private collection.)匿名匿名 |
€ 98.15
Enthält 0% MwSt.
|
日期不详 · Engraving
· 图片ID: 918233
Private Collection / Bridgeman Images |
0 评测 |