 By February 1916 , however , there was no apparent sign of any unusual military activity in the Sinai itself , when the British began construction on the first 25 @-@ mile ( 40 km ) stretch of 4 @-@ foot @-@ 8 @-@ inch ( 1 @.@ 42 m ) standard gauge railway and water pipeline from Kantara to Romani and Katia . Reconnaissance aircraft of the Royal Flying Corps and seaplanes of the Royal Naval Air Service found only small , scattered Ottoman forces in the Sinai region and no sign of any major concentration of troops in southern Palestine . 
