a—3a.

46

Table 23. —Strength-development Studies with Tawa Sulphite: Laboratory Runs.

Table 24. —Strength-development Studies with Tawa Sulphite: Commercial Beater Runs —Consolidated Water-power and Paper Co.

Bursting Factor Run No. Equipment. Pulp usod. Beating-time. 1 (on Oven-dry Freeness. Hand-sheets). Cook No. Minutes. Pts./lb./rm. c.e. 1 Marx-beater .. 2 20 0-16 385 40 0-21 332 60 0-33 295 80 0-35 253 100 0-37 217 120 0 40 168 140 0-46 104 160 0-54 56 2 Rod mill .. 2 20 0-24 258 40 0-32 235 60 0-30 168 ■ , 80 0-37 124 100 0-46 84 3 Marx-beater .. 2 40 0-17 323 70 0-22 292 100 0-32 157 130 0-41 107

Bursting Date. EoU .„ tBng . *"""«■ Hand-sheets). Minutes. Pts./lb./rm. c.c. 1 March 13, 1928 .. Unbeaten stock .. .. 0-08 498 50 Light brush .. .. 0-12 430 90 „ .. .. 0-15 180 Medium brash .. 0-16 340 240 „ .. 0-16 330 300 Hard brush .. . . 0-16 340 360 „ .. .. 0-15 340 2 March 13, 1928 .. 60 Medium brush .. 0-13 440 120 „ .. 0-13 360 180 Hard brush .. .. 0-14 315 240 „ .. .. 0-20 320 300 „ .. .. 0-16 320 3 March 14, 1928 .. 60 Light brush .. 0-17 375 120 Medium brush .. 0-17 315 240 Very hard brush .. 0-18 320 375 „ .. 0-24 265 525 „ .. 0-26 220 Total furnish* .. .. 0-22 175 4 March 14, 1928 .. 60 Light brush . . . . 0-1.6 380 195 Medium brush .. 0-18 320 330 Hard brush .. . . 0-19 270 420 Very hard brush . . 0-25 270 480 „ .. 0-24 250 5 March 14, 1928 . . 60 Hard brush .. . . 0-16 370 120 „ .. .. 0-21 380 210 „ .. .. 0-19 400 Total furnish* .. .. 0-24 160 6 March 14, 1928 .. 60 Hard brush .. .. 0-15 390 120 „ .. .. 0-17 360 210 „ .. .. 0-22 390 Total furnish* .. . . 0-24- 175 7 March 15, 1928 .. 0 Hard brush .. .. 0-11 400 60 „.. .. 0-11 440 Total furnish* . . .. 0-19 225 8 March 15, 1928 .. 90 Hard brush . . .. 0-17 350 Total furnish* .. .. 0-21 230 * This sample comprised the total beater furnish of insignis-pine sulphite, tawa sulphite, alid tawa groundwood, just prior to emptying the beater. All other tests are upon tawa sulphite only.