| 其他書名 | Delivered Before the Committee on Mines and Mining of the House of Representatives of the United States of America, Monday, April 22, 1872 |
| 出版 | M'Gill & Witherow, printers, 1872 |
| URL | http://books.google.com.hk/books?id=1vEKAQAAIAAJ&hl=&source=gbs_api |
| EBook | FULL_PUBLIC_DOMAIN |