▁the ▁entry ▁" Y ork s ▁ 8 ▁Islands ," ▁and ▁under ▁related ▁remarks ▁in ▁Clark ' s ▁" C ree ks ▁and ▁R ivers " ▁is ▁" W . C . ▁on ▁land ▁York ▁tired ." ▁ ▁On ▁Wed nes day , ▁July ▁ 2 4 , ▁ 1 8 0 5 , ▁Mer iw ether ▁Lewis ▁made ▁the ▁following ▁journal ▁entry , ▁which ▁describes ▁his ▁thoughts ▁about ▁the ▁formation ▁of ▁York s ▁Islands : ▁ ▁we ▁saw ▁many ▁be aver ▁and ▁some ▁ot ter ▁today ; ▁the ▁former ▁dam ▁up ▁the ▁small ▁channels ▁of ▁the ▁river ▁between ▁the ▁islands ▁and ▁comp ell ▁the ▁river ▁in ▁these ▁parts ▁to ▁make ▁other ▁channels ; ▁which ▁as ▁soon ▁as ▁it ▁has ▁effect ed ▁that ▁which ▁was ▁stopped ▁by ▁the ▁be aver ▁becomes ▁dry ▁and ▁is ▁filled ▁up ▁with ▁mud ▁sand ▁gra vel ▁and ▁dr ift wood . ▁ ▁the ▁be aver ▁is ▁then ▁comp elled ▁to ▁seek ▁another ▁spot ▁for ▁his ▁habit ation ▁wh er [ e ] ▁he ▁again ▁ere ct s ▁his ▁dam . ▁ ▁thus ▁the ▁river ▁in ▁many ▁places ▁among ▁the ▁clusters ▁of ▁islands ▁is ▁constantly ▁changing ▁the ▁direction ▁of ▁such ▁sl u ices ▁as ▁the ▁be aver ▁are ▁capable ▁of ▁stop ing ▁or ▁of ▁ 2 0 ▁y ds ▁in ▁width . ▁ ▁this ▁an am al ▁in ▁that ▁way ▁I ▁believe ▁to ▁be ▁very ▁instrument al ▁in ▁adding ▁to ▁the ▁number ▁of ▁islands ▁with ▁which ▁we ▁find ▁the ▁river ▁cr oud ed . ▁ ▁The ▁capt ains ▁followed