Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: POSITION OF LINE SHAFT 17 planking, steel plates at the points of greatest wear, the grizzly apron, the point where the ore drops into the bin, and just above each feed-chute .opening. The lower 3 ft. of the planking on the front of the bin should be placed on the outside of the bin-posts, instead of inside, as the remaining planking. This will permit the millman to insert a bar or shovel from the cam-floor and to start the ore when it is low or has 'bridged', or it will enable him easily to enter the bin; a cover of canvas, or a hinged board, between the outside and inside planking will keep the dust back. It is possible to increase the size of the mill by taking a feed-chute put of the corner of the bin and at an angle to it, to another 5-stamp battery in line with the original batteries. One side of the mill is always free to make such an addition, while the other will usually require some change in the driving arrangements. Where this idea is kept in view in building a 10-stamp mill, and a large high bin is built, it will be possible to turn it into a 20-stamp easily and cheaply. In battery construction, the back-knee type, where the battery-posts are tied to the ore-bin, and the line-shaft driving the cam-shafts is placed on the streak-sills underneath the feeder-floor, is now given the preference. This style requires the least amount of timber. It is the strongest and most rigid construction, especially in view of the belt pull. It gives a clean-cut and well-lighted mill, with the upper part of the battery'and mill in sight from the plate-floor. The objections are that a belt-tightener must be used on the battery belts, but this answers for the friction-clutch with which the pulleys of all horizontal battery belts should be provided. However, the wear andtear on the...