. ▁ ▁The ▁specification ▁was ▁accepted ▁on ▁ 2 5 ▁October ▁ 1 7 8 1 ▁and ▁en rolled ▁on ▁ 2 3 ▁February ▁ 1 7 8 2 . ▁ ▁Pat ent ▁ 1 , 3 2 1 : ▁ ▁New ▁improvements ▁upon ▁steam ▁engines   – ▁exp ans ive ▁and ▁double ▁acting . ▁ ▁The ▁specification ▁was ▁accepted ▁on ▁ 1 4 ▁March ▁ 1 7 8 2 ▁and ▁en rolled ▁on ▁ 4 ▁July ▁ 1 7 8 2 . ▁ ▁Pat ent ▁ 1 , 4 3 2 : ▁ ▁New ▁improvements ▁upon ▁steam ▁engines   – ▁three ▁bar ▁motion ▁and ▁steam ▁carriage . ▁ ▁The ▁specification ▁was ▁accepted ▁on ▁ 2 8 ▁April ▁ 1 7 8 2 ▁and ▁en rolled ▁on ▁ 2 5 ▁August ▁ 1 7 8 2 . ▁ ▁Pat ent ▁ 1 , 4 8 5 : ▁New ly ▁improved ▁methods ▁of ▁construct ing ▁furn aces . ▁The ▁specification ▁was ▁accepted ▁on ▁ 1 4 ▁June ▁ 1 7 8 5 ▁and ▁en rolled ▁on ▁ 9 ▁July ▁ 1 7 8 5 . ▁ ▁References ▁ ▁S ources ▁ ▁" Some ▁Un pub lished ▁Let ters ▁of ▁James ▁W att " ▁in ▁Journal ▁of ▁Institution ▁of ▁Mechan ical ▁Engine ers ▁( Lond on , ▁ 1 9 1 5 ). ▁ ▁Car neg ie , ▁Andrew , ▁James ▁W att ▁University ▁Press ▁of ▁the ▁Pacific ▁( 2 0 0 1 ) ▁( Re print ed ▁from ▁the ▁ 1 9 1 3