| 摘要 |
A precipitation gauge including a clear elongated outer cylinder and an opaque or translucent inner member disposed longitudinally in the outer cylinder to define a tubular water receiver in the space between the cylinder and the inner member and markings disposed along either the outer cylinder or the inner member, the gauge indicating the amount of water collected in the water receiver with a sharp demarcation at the top surface of the water resulting from an optical illusion making it appear that the portion of the gauge below the demarcation is filled with a fluid of the color of the inner member.
|
