India Heliograph Diagram 1911
This is the foldout figure facing page 277 of the 1911 Signalling Manual[1] in Appendix II: INDIAN SUPPLEMENT TO THE TRAINING MANUAL SIGNALLING.
This is the heliograph used in India (which differed in many small ways from the Mance heliograph), for which the parts list is on the facing page 277 (and also in this album)
I believe this image to be in the public domain in the US, as a work published prior to 1923, and elsewhere in the world, as a Crown Copyright work published more than 50 years ago[2]. I don't claim that the simple act of reproducing this image earns me copyright, but if others differ, I dedicate any such rights to the public under a CC0 license.
[1] "TRAINING MANUAL –– SIGNALLING, 1907. [REPRINTED, WITH AMENDMENTS, to 1st MAY, 1911.], GENERAL STAFF, WAR OFFICE. LONDON: PUBLISHED BY HIS MAJESTY'S STATIONERY OFFICE.
[2]The title page says "All Rights Reserved", but since it was produced by the War Office, I would expect that to be the same as Crown Copyright, which expires 50 years from publication.
India Heliograph Diagram 1911
This is the foldout figure facing page 277 of the 1911 Signalling Manual[1] in Appendix II: INDIAN SUPPLEMENT TO THE TRAINING MANUAL SIGNALLING.
This is the heliograph used in India (which differed in many small ways from the Mance heliograph), for which the parts list is on the facing page 277 (and also in this album)
I believe this image to be in the public domain in the US, as a work published prior to 1923, and elsewhere in the world, as a Crown Copyright work published more than 50 years ago[2]. I don't claim that the simple act of reproducing this image earns me copyright, but if others differ, I dedicate any such rights to the public under a CC0 license.
[1] "TRAINING MANUAL –– SIGNALLING, 1907. [REPRINTED, WITH AMENDMENTS, to 1st MAY, 1911.], GENERAL STAFF, WAR OFFICE. LONDON: PUBLISHED BY HIS MAJESTY'S STATIONERY OFFICE.
[2]The title page says "All Rights Reserved", but since it was produced by the War Office, I would expect that to be the same as Crown Copyright, which expires 50 years from publication.