| Topic | Relevant Location | Description. |
| India | Telegraph lines | 1867 Report on Ocean Postal Comunication including discussion about the telegraph lines to India and the extent of the lines in - see part 2 "As regards the Telegraph Service". |
| Advertising | Examples of revenue generating advertisements. | |
| Indigenous | Australia | Telegram from Stan Davey to Prime Minister Harold Holt. |
| Western Australia | Release of a group from Hall's Creek after being charged with making spearheads from insulators. | |
| International labels | Australia | Labels to be affixed to telegrams to show message originated from overseas. |
| Interruptions to the lines. | Handstamps. | Instructional markings |
| Examples in summary of interruptions in Victoria. | See the various Annual Reports for Victoria - for example: 1862 Report, Appendix B; 1872 Report, Appendix C; 1874 Report, Appendix B. |
|
| Caused by various birds | Cockatoos. | |
| Magpies. | ||
| Turkeys. |
