▁for ▁deployment ▁in ▁mid - F ebru ary ▁ 1 9 1 5 . ▁In ▁the ▁spring ▁of ▁that ▁year , ▁there ▁was ▁constant ▁under ground ▁fighting ▁in ▁the ▁Y pres ▁Sal ient ▁at ▁Ho oge , ▁Hill ▁ 6 0 , ▁Railway ▁Wood , ▁San ctu ary ▁Wood , ▁St ▁E lo i ▁and ▁The ▁Bl uff ▁which ▁required ▁the ▁deployment ▁of ▁new ▁draft s ▁of ▁t unn ellers ▁for ▁several ▁months ▁after ▁the ▁formation ▁of ▁the ▁first ▁eight ▁companies . ▁The ▁lack ▁of ▁suit ably ▁experienced ▁men ▁led ▁to ▁some ▁t unn elling ▁companies ▁starting ▁work ▁later ▁than ▁others . ▁The ▁number ▁of ▁units ▁available ▁to ▁the ▁BE F ▁was ▁also ▁restricted ▁by ▁the ▁need ▁to ▁provide ▁effective ▁counter - me asures ▁to ▁the ▁German ▁min ing ▁activities . ▁To ▁make ▁the ▁t unn els ▁sa fer ▁and ▁quick er ▁to ▁deploy , ▁the ▁British ▁Army ▁en list ed ▁experienced ▁coal ▁min ers , ▁many ▁outside ▁their ▁nom inal ▁rec ruit ment ▁policy . ▁The ▁first ▁nine ▁companies , ▁numbers ▁ 1 7 0 ▁to ▁ 1 7 8 , ▁were ▁each ▁commanded ▁by ▁a ▁regular ▁Royal ▁Engine ers ▁officer . ▁These ▁companies ▁each ▁compr ised ▁ 5 ▁officers ▁and ▁ 2 6 9 ▁sa ppers ; ▁they ▁were ▁a ided ▁by ▁additional ▁inf antry men ▁who ▁were ▁tempor arily ▁attached ▁to ▁the ▁t unn ellers ▁as ▁required , ▁which ▁almost ▁double d ▁their ▁numbers . ▁ ▁The ▁success ▁of ▁the ▁first ▁t unn elling ▁companies ▁formed ▁under ▁N orton -