and a half miles an hour for ever and ever, but if an army suddenly
takes it into its head to advance twenty miles the camel must somehow go
with it, and some quicker form of transport must be organised behind to
supplement his work.

Thus, born of urgent need, the Railway Operating Division came into being,
and set about the construction of a railway. The difficulties at the outset
were enormous. Not only was the line required quickly to follow in the wake
of the now steadily advancing army, but transport had to be arranged to
bring material from the docks to the railway in embryo. Again the camels
stepped into the breach, and daily long convoys carrying stones and
sleepers and rails went forward into the desert and dropped their loads at
places appointed along the proposed route.

Another and more serious trouble was the lack of men; for if the engineers
had to scour the army for men to make and organise the water-transport,
they had to use a fine comb to get the railwaymen, since only a small
percentage had been allowed to enlist in the first place. However, by the
aid of the system aforementioned, they got together sufficient to meet the
needs of the moment. The bulk of the men had originally been recruited from
two of the great English railways, and either by accident or design,
probably the latter, the authorities kept the men from each railway in
separate companies.

The keenness was terrific. Right from the moment when the railway first
thrust its shining tentacles across the desert, there was a competition
between the two as to which could lay the longer stretch of line in a day's
work. Aided and abetted by the "Camels" and the E.L.C., they progressed at
an astonishing pace, and in spite of all drawbacks from sand and the
terrible heat, an average rate of one mile of line a day was maintained.

To the uninitiated it may seem that railway-making in the desert is a mere
matter of dropping sleepers on to the sand as far as you want to go,
bolting the rails on to them, and running non-stop expresses at once. On
the contrary, except that no rivers had to be bridged nor tunnels made,
laying a line over the desert requires at least as much care and
preparation as elsewhere. For if there is one thing certain about this
unchanging land, it is that the contours of the desert are eternally
changing. The sand is continually silting, and a khamseen may alter the
whole surface of the land, yet to the eye it remains substa