85. Iron Sap Spout, possibly late 19th century. USNM 194893; 1952. A cast-iron maple sap spout, about 3 inches long, used for gathering the sap into buckets. Possibly factory-made and used later than the frontier period, after maple syrup manufacture had become a commercial enterprise. The leading areas for maple syrup have long been Ohio, New York, Vermont, and New Hampshire. Gift of Frank E. Olmstead, Potsdam, New York. 86. Iron Sap Spout, possibly late 19th century. USNM 194893; 1952. A thin, metal trough, plated, and about 3 inches long, used to convey maple sap from the tap in the tree to the sap bucket. This is the type spout most commonly used today in those areas where farmers supplement their income with maple syrup production. Gift of Frank E. Olmstead, Potsdam, New York. 87. Sap Bucket Spikes, possibly late 19th century. USNM 194893; 1952. Hand-made iron spikes used to hold buckets for maple tree sap. They had to be hooked somewhat so the bucket could hang on them well. Gift of Frank E. Olmstead, Potsdam, New York. 88. Diagram of Jefferson Moldboard, 1798. USNM 198605; 1953. A three-dimensional wire diagram, at half scale, illustrating Thomas Jefferson's design of a plow mold-board as he described it in a letter to Sir John Sinclair in 1798. In the same year Jefferson read a paper to the American Philosophical Society that was titled "Description of a Mold-Board of the Least Resistance and of the Easiest and Most Certain Design." The wire diagram was constructed by the Division of Crafts and Industries, Smithsonian Institution. 89. Model of Jefferson Moldboard, 1798. USNM 198605; 1953. The model consists of four separate blocks of wood cut to show the progressive steps in the construction of the Jefferson moldboard: (1) the block of wood marked for sawing with the rear section cut out, and in two parts; (2) the block of wood sawed on two diagonals, with the rear section cut out, and in three parts; (3) the block of wood sawed transversely on guide lines down to the diagonals, with the wood between the transverse cuts removed and leaving the face of the moldboard roughly shaped; (4) the rear surface of the board produced in the same manner as the front, resulting in a completed moldboard. The models were constructed by the Division of Crafts and Industries, Smithsonian Institution, after Jefferson's original moldboard, located at the Natural History Museum, Paris, France. 90. Wooden Curd Breaker, about 1860. USNM 198617; 1953. This curd breaker is made of wood with iron pegs in the cylinder and hopper. Gift of Laurence Hathaway, Easton, Maryland. [Illustration: Figure 9.--Grain cradle in use in the field. International Harvester Corporation photo. (Catalog No. 91.)] 91. Grain Cradle, about 1844. USNM 198620; 1953. Caleb Paul Duval used this cradle on his Glen Echo farm near Baltimore, Maryland. Gift of Virginia Duval, College Park, Maryland.