Thank you all very much for your input--
Mini-me, thanks for your license tag info, does the number indicate that this would have been the 1826th motorcycle registered in the Nottingham district?
What year did the govenment begin issuing license tags for motorcycles?
R - Great info & research in order to find an original illustration depicting the correct bike! As to the power requirements for the transmitter, I think that the cables that disappear to the left of the bike indicate where the power source (most likely storage batteries) was located... was it another bike so that the power plant was mobile? I guess we will never know. I presume this was the apparatus of a an early radio amateur operator (Ham radio) and since this was so early in the development of the art, he "rolled his own" (Homebrew) the power source, antenna and receiver of the installation. The Marconi spark coil & gap would have weighed about 100 lbs, so this bike must have been a bear to handle on the rough roads of the day! This spark coil is mounted on the rear fender and the mounting bracket was built by the radio operator. A Morse Telegraph Spark key may have been mounted out of sight on the handlebars, and the crystal receiver is also not shown in the image. I don't recognize any military apparatus or badges, which indicates this was just a private citizen pushing the envelope on mobile wireless... think 1912 Cell Phone...
Cardan--- Thank you so much for confirming that it is indeed a Campion and providing exact details on the engine & running gear. It is an interesting explanation of the Roc gear assembly.
And Rex --- you are absolutely correct, I never thought I would acquire this much info & details on such an obscure bike in such a short amount of time.
This website is full of knowledgeable people who are not afraid to share their knowledge they have gained thru the years!
If anyone discovers an earlier application of a wireless set on a motorcycle, please contact me with the details, as this is a very important subject in our field. I will be sharing this website entry with the Curator of Science and Technology at the Science Museum in London, who is a personal friend.
I am running an image in our quarterly Journal and this information will help me to correctly identify the model & vintage of the Campion. This photo represents the cutting edge technology of mobile radio before WWI !!!
***** A few years ago I discovered another glass side that depicted an American motorcycle with a wireless outfit built into the sidecar & I was able to post a question on the Indian forum and they helped me out just like you fellows did! I will post details and a couple of photos in a few minutes, hoping that some of you might enjoy seeing what a complete DeForest Wireless station (He invented the triode vacuum tube) looked like on an American Indian in 1917.
Thank you again for all your help!
73 Jim