res can realise what it means to
fly right over the stronghold at four thousand feet. The advanced lines
of communication that stretch westward to the Arras-Peronne front all
hinge on Pluspres, and for this reason it often shows activity of
interest to the aeroplane observer and his masters. The Germans are
therefore highly annoyed when British aircraft arrive on a tour of
inspection. To voice their indignation they have concentrated many
anti-aircraft guns around the town. What is worse, the Archie fire at
Pluspres is more accurate than at any other point away from the actual
front, as witness the close bracket formed by the sighting shots that
greet our solitary bus.

From a hasty glance at the station and railway lines, while we slip away
to another level, I gather that many trains and much rolling stock are
to be bagged. The work will have to be done under serious difficulties
in the shape of beastly black bursts and the repeated changes of
direction necessary to dodge them. We bank sharply, side-slip, lose
height, regain it, and perform other erratic evolutions likely to spoil
the gunners' aim; but the area is so closely sprinkled by shells that,
to whatever point the machine swerves, we always hear the menacing
report of bursting H.E.

It is no easy matter to observe accurately while in my present condition
of "wind up," created by the coughing of Archie. I lean over to count
the stationary trucks in the sidings. "_Wouff_, _wouff_, _wouff_,"
interrupts Archie from a spot deafeningly near; and I withdraw into "the
office," otherwise the observer's cockpit. Follows a short lull, during
which I make another attempt to count the abnormal amount of rolling
stock. "_Wouff--Hs--sss!_" shrieks another shell, as it throws a large
H.E. splinter past our tail. Again I put my head in the office. I write
down an approximate estimate of the number of trucks, and no longer
attempt to sort them out, so many to a potential train. A hunt over the
railway system reveals no fewer than twelve trains. These I pencil-point
on my map, as far as I am able to locate them.

A massed collection of vehicles remain stationary in what must be either
a large square or the market-place. I attempt to count them, but am
stopped by a report louder than any of the preceding ones. Next instant
I find myself pressed tightly against the seat. The whole of the machine
is lifted about a hundred feet by the compression from a shell that has
exploded a f