rons ▁and ▁only ▁with ▁difficulty ▁was ▁Case y ▁able ▁to ▁control ▁their ▁activities . ▁ ▁Case y ' s ▁initial ▁need ▁was ▁for ▁engineer ▁units ▁to ▁accomplish ▁the ▁da un ting ▁construction ▁program , ▁but ▁soon ▁stock s ▁of ▁engineer ▁supplies ▁and ▁equipment ▁began ▁to ▁run ▁low . ▁This ▁was ▁ex ac erb ated ▁by ▁incoming ▁units ▁arriv ing ▁without ▁their ▁equipment , ▁or ▁with ▁it ▁st owed ▁on ▁numerous ▁ships , ▁which ▁often ▁arrived ▁at ▁various ▁ports ▁in ▁a ▁the ater ▁where ▁ports ▁were ▁hundred ▁or ▁thousands ▁of ▁miles ▁apart . ▁Crit ical ▁short ages ▁developed ▁of ▁tra ctors , ▁grad ers , ▁concrete ▁mix ers ▁and ▁w eld ing ▁equipment . ▁In ▁the ▁absence ▁of ▁a ▁proper ▁stock ▁control ▁system , ▁an ▁overall ▁coordin ating ▁ag ency , ▁and ▁ade qu ate ▁numbers ▁of ▁engineer ▁dep ot ▁units , ▁the ▁allocation ▁and ▁distribution ▁of ▁the ▁me ager ▁supplies ▁on ▁hand ▁were ▁difficult ▁tasks . ▁The ▁worst ▁problem ▁was ▁spare ▁parts . ▁Equ ip ment ▁was ▁operated ▁around ▁the ▁clock ▁under ▁har sh ▁conditions ▁and ▁soon ▁wore ▁out ▁or ▁broke . ▁A ▁large ▁proportion ▁of ▁equipment ▁became ▁un service able ▁for ▁lack ▁of ▁spare ▁parts . ▁Re quis itions ▁sent ▁to ▁the ▁United ▁States ▁took ▁months ▁to ▁arrive , ▁so ▁rec ourse ▁was ▁made ▁to ▁the ▁limited ▁sources ▁of ▁supply ▁in ▁Australia . ▁ ▁In ▁September ▁ 1 9 4 2 , ▁Mac Ar thur ▁decided ▁to ▁out fl ank ▁Japanese ▁troops ▁on ▁the ▁K ok oda ▁Tra il ▁by ▁sending ▁an