58 



BULLETIN" 343, U. S. DEPARTMENT OF AGRICULTURE. 



Table 2. — Furnish to beater on basis of 1,000 pounds of paper. Commercial tests on 



experimental pulps. 



Stock 

 No. 



Kind of ground wood. 



Weight. 



Sulphite. 



Size. 



Alum. 



Soluble 

 blue HA. 



Pounds. 



Pounds. 



Pounds. 



Pounds. 



Ounces. 



750 



250 



3.33 



6.67 



3.2 



750 



250 



3.33 



6.67 



4.27 



750 



250 



3.33 



6.67 



3.37 



750 



250 



3.33 



6.67 



3.33 



750 



250 



3.33 



6.67 



4.27 



750 



250 



3.33 



6.67 



2.53 



750 



250 



3.33 



6.67 



3.2 



750 



250 



3.33 



6.67 



3.73 



!750 



250 



3.33 



6.67 



3.73 



!750 



250 



3.33 



6.67 



2.6 



750 



250 



3.33 



6.67 



5.33 



!750 



250 



3.33 



6.67 



4.00 



800 



200 



3.33 



10.0 



5.4 



800 



200 



3.33 



10.0 



4.4 ' 



800 



200 



3.33 



10.0 



6.8 



800 



200 



3.33 



10.0 



4.8 



800 



200 



3.33 



10.0 



5.0 



Rhodamine 

 B extra. 



Spruce 



Western hemlock 



Sitka spruce 



Lodgepole pine (Montana) 



Western yellow pine 



Balsam fir 



Lodgepole pine (California). . . 



Red fir 



Hemlock and spruce 



Balsam and spruce 



Tamarack 



Tamarack and spruce 



Noble fir 



Alpine fir 



White fir 



Engelmann spruce (Colorado) 

 Amabilis fir 



Ounces. 

 0.167 

 .10 

 .167 

 .20 

 .267 

 .167 

 .167 

 .133 

 .20 

 .167 

 .667 

 .4 

 .40 

 .40 

 .30 

 .375 

 .400 



1 375 pounds each. 



The remainder of the 12 tests were run on a Fourdrinier machine 

 trimming 100 inches and provided with a suction couch roll. The 

 operation of pulp on this machine was much more satisfactory than 

 on the other, although slowness of the stock made it impossible to use 

 the dandy and a good formation could not be secured. Both of the 

 paper machines ran at a speed of 460 feet per minute, and the screen 

 plates were cut with slots 0.011 inch wide. In calendering the paper, 

 9 nips of a 12-roll calender stack were used. 



So far as appearance and strength went, all the sheets manufac- 

 tured at this time were considered very creditable. The No. 9 paper, 

 containing 37J per cent of hemlock ground wood, 37| per cent of 

 spruce ground wood, and 25 per cent of quick-cook hemlock sulphite, 

 had a very high strength and took an excellent finish, though the 

 color was slightly off. Both of the balsam sheets — No. 6 and No. 

 10 — were very good both in strength and color. The western yellow- 

 pine sheet ran very foamy and showed a number of scum spots, due 

 largely to the pitch. Sheets of better formation undoubtedly could 

 have been made if the pulp had been ground in a way to make it some- 

 what more "free." The Jordan machine was not used except to 

 brush out the sulphite. 



For the last 5 of the 17 commercial runs it was necessary to return to 

 the first paper machine. In this series the paper was run at a speed of 

 450 feet per minute and passed through 11 nips of a 12-roll calender 

 stack. All of the stocks were somewhat slow, but not so slow as were 

 those of the previous series. The formation of the sheets, however, 

 left much to be desired. Engelmann spruce (stock 16) and Alpine fir 

 (stock 14) operated very satisfactorily with the dandy in use, but 

 the stock from amabilis fir (stock 17) was very slow and sticky, and 

 the dandy was removed for noble fir (stock 13) and white fir (stock 



