| 摘要 |
<p>The watering trough, for animals such as rabbits, may be of plastic material. It is inserted through a hole in a wall of an enclosure with a chamber containing automatic water level control apparatus. On the other side of the wall. The three sides of the trough in the enclosure are covered by a metal band which masks the hole when the trough is withdrawn. The band also serves to protect the trough from attack by the animal. The upper edge of the trough is protec ted by a turned over lip.</p> |
