Roasting jack or spit engine consisting of a tall, slender, cylindrical shaft with astragal-arched hanging loop mounted on top of a larger cylinder containing a spring-powered mechanism that winds up with the attached key; conical turning tip with small suspension hook extends through opening in the flat hexagonal base plate and rotates both clockwise and counterclockwise for even roasting. Keyhole with swing cover on front above a semicircular nameplate embossed "JOHN LINWOOD" in a scroll-ended, beaded band arched over an oak tree and "WARRANTED" across bottom. Underside of base plate struck incuse "10" with "WARRANTED" curved below.
Maker is John Linwood of Birmingham, England. He is believed to have started making roasting jacks around 1800 and registered his oak tree mark at the Birmingham assay office in 1807. He was succeeded by E.B. Bennett & Co. (active mid 19th century) who continued using his name and trademark.