The mine cables are coiled in figure 8’s. In order to secure uniformity in the size of the coils, they may be coiled on a rack (improvised at the post). This rack is made of one 12-foot length of 4 by 6-inch scantling, crossed at right angles by two 6-foot lengths (4 by 6 inch) placed 5 feet apart. Four 1-inch holes are bored through each of the timbers about 2 feet from each of the crossings, and a 2-foot length of gas pipe is inserted in each hole. These pipes make the form on which the coils are made. A cable must be coiled for planting so that both ends are free, one to be passed to the distribution box boat, the other to be carried forward on the planter and attached to the mine. This is accomplished by starting the coil about 135 feet from the mine-cap end, the approximate length required to run forward when using a mine planter. The cable is coiled on the form, spreading out the laps at the center to reduce the height at that point, until the entire length is coiled. The outer loops and the center of the figure 8 coil are lashed, leaving the ends sufficiently long to lash the part of the cable remaining uncoiled. The mine-cap end of the cable is then coiled on top of the coil and lashed with the ends of the rope. Single-conductor cables when coiled should be tested for continuity of circuit and grounds before being placed aboard the planter. For continuity of circuit the two ends of the cable are connected to a battery and voltmeter in series. If the cable has no break, the reading of the voltmeter should show approximately the same deflection as when the battery circuit and voltmeter alone are in circuit. To test for a ground the cable is submerged in a testing tank, leaving both ends out. It is advisable, when practicable, to extend a lead from one of the operating boards of the mining casemate to the cable tank. One end of the cable to be tested is connected to this lead and the test made as prescribed for “insulation test” on page 44. The condition of a multiple-conductor cable can be quickly determined by this arrangement. If the above method is not practicable, a dry-cell battery with a mil-ammeter and protective lamp may be installed at the cable tank; or, in place of the mil-ammeter and lamp, a voltmeter placed in series with the battery and cable may be used, the resistance being obtained by the voltmeter method. One side of the battery should be grounded by touching the cable armor or by using an earth plate. In actual service, cable which tests under 1 megohm should not be used; for practice, cable under 10,000 ohms should not be used. If post power is used as a source of energy for testing, the system should be free from grounds. Care should be taken to have the cable ends and battery leads free from grounds and dry.