356. Steel Mink Trap, 1876. USNM 4772; 1966. This trap has a single spring and a jaw spread of 4-7/8 inches. Gift of Oneida Community, New York. 357. Steel Muskrat Trap, 1876. USNM 4772; 1966. This muskrat trap has a single spring and a jaw spread of 4 inches. Gift of Oneida Community, New York. 358. Steel Rat Trap, 1876. USNM 4772; 1966. This trap has a single spring and a jaw spread of 3-1/2 inches. Gift of Oneida Community, New York. 359. Bottle of 2,4-D Herbicide, 1944. USNM 268668; 1966. This bottle contains a small amount of the original purchase of 2,4-D by the U. S. Department of Agriculture from the American Chemical and Paint Company of Ambler, Pennsylvania, in 1944. It cost $12.50 a pound at the time. Scientists at the Department of Agriculture used the material in extensive experiments on plant growth inhibitors. Subsequently, 2,4-D became the most common chemical used for weed killing. Gift of Dr. J. W. Mitchell, University of Maryland, through Gale Peterson, University of Maryland. 360. Winnowing Machine, mid 19th century. USNM 270009; 1966. Typical mid-19th-century fanning mill with vibrator cleaner. Gift of Mrs. Henry C. Slunt, Hyattsville, Maryland. 361. Winnowing Machine, mid 19th century. USNM 270009; 1966. Typical mid-19th-century fanning mill with screen vibrator cleaner. Gift of Mrs. Henry C. Slunt, Hyattsville, Maryland. [Illustration: Figure 29.--John Deere Model D tractor, 1923. (Catalog No. 362.)] 362. John Deere Model D Tractor, 1923. USNM 270865; 1967. The John Deere Model D was the first tractor of the line bearing that name. The Waterloo Tractor Works, Waterloo, Iowa, made the tractor in 1923. Gift of Deere & Company, Moline, Illinois, through George F. Neiley. 363. Waterloo Boy Model N Tractor, 1918. USNM 270864; 1967. The Waterloo Boy tractor was manufactured first as Model R, in 1914, and then as Model N, beginning in 1918. The Waterloo Gasoline Engine Company of Waterloo, Iowa, made the Waterloo Boy. It was the first tractor marketed by the John Deer Company, which acquired the Waterloo Gasoline Engine Company in 1918. The Waterloo Boy continued to be produced by John Deere Company until 1923, when that company brought out its own Model D. Gift of Deere & Company, Moline, Illinois, through George F. Neiley. [Illustration: Figure 30.--Cheese press. (Catalog No. 364.)] 364. Cheese Press, late 19th century. USNM 170886; 1967. Small, wooden, hand-operated cheese press, dating from the late 19th century but not unlike those in use a century before. Gift of Carlton M. Gunn, Sunderland, Massachusetts, through Allister F. MacDougall.