This trip was a complete surprise because I understood from my meager instructions that even when crossing the line the enemy anti-aircraft artillery, commonly called “the archies,” would certainly open fire, but everything was calm and peaceful—except my mind. I looked at my map to find where the panels were displayed. Panels are large, horizontal strips of cloth which are placed on the ground in various symbols near the battery and are used as a means of communication between the battery and the airplane. The airplane communicates with the battery largely by means of the radio telegraphy, but as it was not practicable to receive the radio signals in the plane from the ground, we used these panels. Among the signals formed by these white panels, which are quite clearly discernible from the air, are those meaning that the “Battery is ready to fire,” “Battery has fired,” “Fire by Salvo,” “Change target,” and many, many others including the signal “There is an Enemy Plane near you,” which is the most dreaded panel that can be displayed. I might incidentally mention that there is another panel which means “There is no further need of you; you can go home.” Now this may not have a great deal of significance to the average layman, but I’ll say that when the sky spy has been tossed about for a couple of hours on the archie billows he joins the union which says that “go home, you’re fired” is the greatest little panel of the whole panel alphabet. So, in a few minutes I picked up the location of the panels and I had a little chart on my map board showing the meaning of these many panels. I had had some instructions upon them while at Observation School, but I had depended on crossing the bridge only upon arrival thereat, so I did not pay a great deal of attention to them. The descriptive chart on my map board interpreted the panels in French so I was not sure that the chart would do me any good after all for my knowledge of technical or any other kind of French was less than meager. I saw the panel “Battery is ready,” and then the plane headed toward the lines and in a moment the panel changed to “Battery has fired,” so I looked over in Hunland but I could not find where the shells had hit. In my mind they were hitting everywhere so how could I pick out the particular ones that Jones was directing. In a moment I again saw “Battery is ready,” and again I looked directly toward the supposed target. Suddenly I saw four shells strike real close by and my vigilance was rewarded for I was to witness an actual adjustment of artillery fire against a real enemy. Then I took a genuine interest in the adjustment and paid very close attention to every detail. In fact, I was so attentive that I was oblivious to the fact that my mission was to protect the leading plane.