Perhaps you should try some spelling variations:
early telegraph » mails telegraph, early typography, early tomography
delay telegraph » der telegraph, solar telegraph, delay tomography
der telegraphie » der telegraph, der telegraphen, fur telegraphie

You may be able to get more results by adjusting your search query.

• If you are trying to use Boolean operators, they must be ALL CAPS: ((early telegraph) OR (((delay telegraph) OR (der telegraphie)))).
• Adding a wildcard symbol may retrieve word variants: ((early telegraph) or (((delay telegraph) or (der telegraphie))))*.