▁and ▁st ole ▁his ▁fortune . ▁ ▁Det ect ive ▁and ▁mystery ▁stories ▁In ▁the ▁late ▁ 1 8 9 0 s , ▁detect ive ▁nov els ▁featuring ▁seem ingly ▁" im possible ▁cr imes " ▁became ▁popular . ▁Im possible ▁cr imes ▁were ▁sometimes ▁carried ▁out ▁using ▁secret ▁pass ages ▁or ▁doors . ▁Sub sequ ent ▁gener ations ▁of ▁detect ive ▁pul p ▁fiction ▁and ▁mystery ▁story ▁authors ▁also ▁used ▁the ▁plot ▁device ▁of ▁secret ▁pass ages . ▁ ▁However , ▁the ▁use ▁of ▁secret ▁pass ages ▁in ▁detect ive ▁fiction ▁and ▁mystery ▁stories ▁has ▁been ▁critic ised , ▁on ▁the ▁grounds ▁that ▁it ▁is ▁not ▁" f air " ▁to ▁expect ▁the ▁reader ▁to ▁guess ▁about ▁the ▁existence ▁of ▁these ▁secret ▁pass ages . ▁Ron ald ▁Kno x ▁( 1 8 8 8 – 1 9 5 7 ), ▁a ▁British ▁the olog ian ▁and ▁detect ive ▁story ▁author , ▁argued ▁that ▁the ▁plot ▁device ▁of ▁a ▁secret ▁passage ▁was ▁over used ▁in ▁detect ive ▁fiction . ▁Kno x ' s ▁Ten ▁Command ments ▁for ▁Det ect ive ▁F iction ▁states ▁that ▁" Not ▁more ▁than ▁one ▁secret ▁room ▁or ▁passage ▁is ▁allow able ." ▁Furthermore , ▁Kno x ▁ur ges ▁that ▁secret ▁pass ages ▁not ▁be ▁used ▁in ▁detect ive ▁stories ▁unless ▁the ▁story ▁takes ▁place ▁in ▁an ▁old ▁house ▁or ▁castle ▁where ▁a ▁reader ▁might ▁reason ably ▁expect ▁to ▁find ▁a ▁secret ▁door ▁or ▁passage way . ▁ ▁Carol yn ▁Well s ' ▁" im possible ▁crime " ▁stories