2 1 5 8 , ▁ 2 9 2 ▁pages , ▁ 1 9 9 8 . ▁http :// pub s . us gs . gov / bul / b 2 1 5 8 / B 2 1 5 8 . pdf ▁ ▁External ▁links ▁▁ ▁M anti ▁La ▁Sal ▁National ▁Forest ▁ ▁Category : Color ado ▁Pl ate au ▁Category : L ac col ith s ▁Category : Mount ains ▁of ▁Grand ▁County , ▁Ut ah ▁Category : Mount ains ▁of ▁San ▁Juan ▁County , ▁Ut ah ▁Category : Mount ain ▁ranges ▁of ▁Ut ah ▁Category : R anges ▁of ▁the ▁Rock y ▁Mountains ▁Category : M anti - La ▁Sal ▁National ▁Forest <0x0A> </s> ▁Gray ▁Marine ▁Motor ▁Company ▁was ▁an ▁important ▁marine ▁engine ▁builder . ▁It ▁built ▁engines ▁r anging ▁from ▁one ▁to ▁six ▁cyl ind ers ▁in ▁both ▁gas ▁and ▁later ▁dies el ▁layout s ▁which ▁were ▁used ▁in ▁pleasure ▁and ▁work ▁boats . ▁ ▁Gray ▁was ▁an ▁American ▁firm , ▁based ▁in ▁Detroit ▁from ▁ 1 9 0 1 ▁until ▁ 1 9 6 7 . ▁Many ▁fish ing ▁boats , ▁lo b ster bo ats , ▁t ugs ▁and ▁pleasure ▁craft ▁used ▁Gray ▁engines . ▁These ▁boats ▁were ▁usually ▁of ▁small ▁size , ▁r anging ▁from ▁ 1 2 ▁to ▁ 3 2 ▁feet . ▁Many ▁of ▁their ▁engines ▁were ▁mar in ized ▁autom ot ive ▁engines ▁from ▁Her cules , ▁St ude b aker , ▁Pont iac , ▁Cont inental , ▁American ▁Mot ors ▁or ▁General ▁Mot