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在防火瞭望台顶部安装有发现森林火灾的电视箱。电视箱不断地绕着防火瞭望台竖轴旋转,其速度每分钟不到半转。电视箱用特殊的透镜装成,在20
The top of the fire observation deck was fitted with a television box for detecting forest fires. The TV box is constantly rotating around the fireproof observatory vertical axis, its speed less than half a minute. TV box with a special lens installed at 20