Complex sentence: Meanwhile, the convoys bringing food and water from Beersheba to the 53rd (Welsh) Division lost their way, the camel convoy carrying the water arrived at 04:30 by which time, some of the mules from one battalion had been 53 hours without a drink.
Split into simpler sentences: Meanwhile, the convoys bringing food and water from Beersheba to the 53rd (Welsh) Division lost their way. The camel convoy carrying the water arrived at 04:30, by which time some of the mules from one battalion had been 53 hours without a drink.