For these many weeks Pozières has been but a name and a waste brick pile; yet the site of the powdered village cannot be mistaken from the air, for, slightly to the east, two huge mine-craters sentinel it, left and right. From here to Le Sars, which straddles the road four miles beyond, was our photographic objective. We were to cover either side of the road twice, so I had arranged to use half the number of plates during each there-and-back journey.
The R.F.C. camera used by us is so simple as to be called foolproof. Eighteen plates are stacked in a changing-box over the shutter. You slide the loading handle forward and backward, and the first plate falls into position. Arrived over the spot to be spied upon, you take careful sight and pull a string—and the camera has reproduced whatever is 9000 feet below it. Again you operate the loading handle; the exposed plate is pushed into an empty changing-box underneath an extension, and plate the second falls into readiness for exposure, while the indicator shows 2. And so on until the changing-box for bare plates is emptied and the changing-box for used ones is filled. Whatever skill attaches to the taking of aerial snapshots is in judging when the machine is flying dead level and above the exact objective, and in repeating the process after a properly timed interval.
A.-A. guns by the dozen hit out immediately we crossed the lines, for we were their one target. No other craft were in sight, except a lone B.E., which was drifted by the wind as it spotted for artillery from the British side of the trenches. Scores of black puffs, attended by cavernous coughs, did their best to put the wind up us. They succeeded to a certain extent, though not enough to hinder the work on hand.
Everything was in Archie's favour. We were at 7000 feet—an easy height for A.-A. sighting—we were silhouetted against a cover of high clouds, our ground speed was only some thirty miles an hour against the raging wind, and we dared not dodge the bursts, however close, as area photography from anything but an even line of flight is useless. Yet, though the bursts kept us on edge, we were not touched by so much as a splinter. In this we were lucky under the conditions. The luck could scarcely have held had the job lasted much longer than a quarter of an hour—which is a consoling thought when one is safe back and writing to a dear friend in England, not?
Northward, along the left-hand side of the road, was my first subject; and a damned unpleasant subject it was—a dirty-soiled, shell-scarred wilderness. I looked overboard to make certain of the map square, withdrew back into the office, pulled the shutter-string, and loaded the next plate for exposure.
"Wouff! Ouff! Ouff!" barked Archie, many times and loud. An instinct to swerve assaulted the pilot, but after a slight deviation he controlled his impulse and held the bus above the roadside. He had a difficult task to maintain a level course. Whereas we wanted to make east-north-east, the wind was due east, so that it cut across and drifted us in a transverse direction. To keep straight it was necessary to steer crooked—that is to say, head three-quarters into the wind to counteract the drift, the line of flight thus forming an angle of about 12° with the longitudinal axis of the aeroplane.
"Wouff! ouff!" Archibald continued, as I counted in seconds the interval to the scene of the next snapshot, which, as assurance that the whole ground would be covered, was to overlap slightly the first. A quick glance below, another tug at the string, and plate the second was etched with information. The third, fourth, and fifth followed; and finally, to our great relief, we reach Le Sars.
Here the pilot was able to dodge for a few seconds while we turned to retrace the course, this time along the southern edge of the road. He side-slipped the bus, pulled it around in an Immelmann turn, and then felt the rudder-controls until we were in the required direction. The interval between successive exposures was now shorter, as the east wind brought our ground speed to 120 miles an hour, even with the engine throttled back. There was scarcely time to sight the objective before the photograph must be taken and the next plate loaded into place. Within two minutes we were again over Pozières.
V. took us across the lines, so as to deceive the Archie merchants into a belief that we were going home. We then climbed a little, turned sharply, and began to repeat our outward trip to north of the road.
Evidently Archie had allowed his leg to be pulled by the feint, and for two minutes he only molested the machine with a few wild shots. But soon he recovered his old form, so that when we had reached Le Sars the bus was again wreathed by black puffs. We vertical-turned across the road and headed for the trenches once more, with the last few plates waiting for exposure.