182. Double-Shovel Plow, about 1850. USNM 230574; 1959. This double-shovel plow has the shovels placed opposite one another. Gift of John Offenbacker, Sidney, Ohio. 183. A-Frame Harrow, mid 19th century. USNM 230574; 1959. This triangular harrow has wooden beams with 22 ten-inch iron spikes driven through them. This type of harrow pulverized and leveled plowed land, covered the seed, and cultivated between rows of corn. Triangular harrows worked better than square types because the triangles had greater strength on newly cleared land. Gift of John Offenbacker, Sidney, Ohio. 184. Trolley Carrier for Hayfork, about 1875. USNM 230574; 1959. This steel trolley carrier supported a one-horse hayfork. A pulley attached to the trolley carrier lifted and lowered the hayfork. The first trolley carriers for hayforks were invented by J. E. Porter of Ottawa, Illinois, in 1869 and 1872. They were made of wood and iron. The first steel carriers were patented by Jacob Ney, Canton, Ohio, and (in 1886) by P. A. Myer, Ashland, Ohio. Gift of John Offenbacker, Sidney, Ohio. 185. Riding Disk Cultivator, late 19th century. USNM 230574; 1959. This cultivator has two sections, each with three 15-inch disk wheels spaced 5-3/4 inches apart. It has handgrip levers for making cutting adjustments. This machine worked best on ground between row crops. Gift of John Offenbacker, Sidney, Ohio. 186. Singletree, late 19th and early 20th centuries. USNM 230574; 1959. This singletree is made of wood. The trace chains of the team of horses could be attached to the hooks on the singletree. Gift of John Offenbacker, Sidney, Ohio. 187. Doubletree, late 19th century to early 20th century. USNM 230574; 1959. A doubletree made of wood. The doubletree served as a lever on which to mount two singletrees. This arrangement distributed equally the pull of a load between two horses. Gift of John Offenbacker, Sidney, Ohio. 188. Singletree, late 19th century. USNM 230574; 1959. The trace chains of two horses are attached to this home-made, wooden singletree. The tongue of a machine would be hooked to the center of the tree. Gift of John Offenbacker, Sidney, Ohio. 189. Grain Fork, about 1870. USNM 230574; 1959. This three-tine iron fork was used to move bundled grain. Gift of John Offenbacker, Sidney, Ohio. 190. One-Row, Hand "Corn Jobber," late 19th century. USNM 230574; 1959. Gift of John Offenbacker, Sidney, Ohio. 191. Double-Harpoon Hay Fork, about 1870. USNM 230574; 1959. S. E. Harris patented this double-harpoon, iron hayfork in 1867. Gift of John Offenbacker, Sidney, Ohio. 192. Ground Hog Thresher, about 1830. USNM 230579; 1959. This early thresher did not separate the grain from the chaff. Grain fed into the trough passed into a compartment with a rotating iron cylinder filled with finger-like projections which broke the grain into its component parts. A fanning basket then separated the grain from the chaff. Purchased from George Rhoades, Greenville, Ohio.