But，indeed，Mr。Martinhadbeforeusedthestrapofleather。

　　ThescrewofArchimedesisasancient，atleast，astheageofthatmathematician，whodiedmorethan2，000yearsago。DiodorusSiculusspeaksofit，L。i。，p。21，andL。v。，p。217，ofStevens’

　　editionof1559，folio；andVitruvius，xii。Thecuttingofitsspiralwormintosectionsforconveyingflourorgrain，seemstohavebeenaninventionofMr。Evans，andtobeafairsubjectofapatentright。ButitcannottakeawayfromotherstheuseofArchimedes’

　　screwwithitsperpetualspiral，foranypurposesofwhichitissusceptible。

　　Thehopper-boyisanusefulmachine，andsofarasIknow，original。

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