 |
| |||
| 炮孔观察镜专门用来观察孔壁的仪器，观察时孔内用灯泡照明。参见 periscope, strata scope | |||
The server is undergoing maintenance and the site is working in read-only mode. Please check back later.">Add | The server is undergoing maintenance and the site is working in read-only mode. Please check back later.">Report an error
| Get short URL | Language Selection Tips