The Mechanical Handling and Storing of Material

3U THE mechanical handling of material tig. 448. Button-Picking Pall-Rope Carrier, showing the Action of the Shock-Absorbing Carrier Head. Among the first travelling cableways constructed by the Lidgerwood Manufacturing Co. were those used on the Chicago Drainage Canal in 1890, and they proved very efficient, but numerous improvements have since been made. Fig. 450 shows details of cableway used on the Chicago Drainage Canal. A later design was employed on the Nebish and Livingstone Channels near the Canadian border, being of the general type employed in the Chicago Drainage Canal. On the Nebish Channel work, 1,600,000 cub. yds. of solid rock place measurement were removed by these cableways to an average depth of 15 to 16 ft., and great economy in loading the skips was effected by the use of steam shovels which had a 2| yds. capacity. The steam cableway skips used were 8 ft. square by 2 ft. 6 in. deep, the weight of the loaded skips averaging 8 tons, and the monthly out- put of the four cableways so in use averaged 65,000 place yds. In one month 76,752 place yds. were the output allowed and paid for by the Government; this represents an average output of 3,073 yds. for each of the twenty- four days. One of the cable- ways made a monthly record of 29,490 yds. place measure- ment. More recent and con- spicuous examples of similar installations are the cable- ways employed in the con- struction of the Gatun Locks, Isthmus of Panama. Thirteen electrically operated Lidgerwood cableways were employed for that work, eight of which, arranged in four pairs, handled the concrete for building the lock, the span in every case being 800 ft., and the loads handled 2 yds. of concrete, or about 6 tons. Similar cableways were used for unloading rock from barges, and depositing the same on storage ground. The span for these was also 800 ft. and each was equipped with a 74 cub. ft. grab bucket. Cableways may be used for a great variety of other purposes. For instance, the