Chap. 11.] CONSTRUCTION OP MACHINES. 225

at the upper edge, holding the saw very much aslant,the point downwards and inwards, so that in bending, theparts will slip past each other. The upper case must benearly straight; for if it be made much crooked, thebuckets will incline to turn under the strap. Make thecases 3-4ths of an inch wider inside, than the strap and.buckets, and inches deeper, that they may play free-ly; but do not give them room to turn upside down. Ifthe strap and buckets be 4 inches, then make the sideboards 5£, and the top and bottom boards 6f inches wide,of inch boards. Be careful that no shoulders nor nail-points be left inside of the cases, for the buckets to catchin. Make the ends of each case, where the buckets en-ter as they pass over the pulleys, a little wider than therest of the case. Both the pulleys are to be nicely casedround to prevent waste, not leaving room for a grain toescape, continuing the case of the same width round thetop of the upper, and bottom of the lower pulley; then, ifany of the buckets should ever get loose, and stand askew,they will be kept right by the case; whereas, if therewere any ends of boards or shoulders, they would catchagainst them. See AB, fig. 1, Plate VI. The bottomof the case of the upper pulley must be descending, sothat what grain may fall out of the buckets in passingover the pulleys, may be guided into the descendingcase. The shaft passing through this pulley is maderound where the case fits to it: half circles are cut outof two boards, so that they meet and embrace it closely.The undermost board, where it meets the shaft, is ci-phered off inside next the pulley, to guide the grain in-ward. But it is full as good a way to have a stronggudgeon to pass through the upper pulley, with a tenonat one end, to enter a socket, which may be in the shaft,that is to give it motion. This will suit best where theshaft is short, and has to be moved to put the elevatorout of, and into gear,

The way that I have generally cased the pulleys is asfollows; namely : The top board of the upper strap-case,and the bottom board of the lower strap-case, are ex-tended past the lower pulley to rest on the floor; and the

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