JACK PINE AND HEMLOCK FOR MECHANICAL PULP. 



The samples of butcher's manila and No. 2 white manila given were 

 made by the Nekoosa-Edwards Paper Co., the furnish being shown in 

 Table 10. These samples are meant merely to give an idea of what 

 can be obtained when mixtures of hemlock and spruce are used. 



The strength of all of the sheets, with the exception of the one made 

 up of hemlock sulphite and jack-pine ground wood, compares well with 

 standard news paper. The paper from run No. 24 has another decid- 

 edly objectionable feature, and that is the loss of finish occasioned by 

 rubbing the sheet with the hand. The fibers under this treatment 

 fuzz up, and considerable powder and short fiber fall off. Several of 

 the other sheets have this same peculiarity, but if more size were 

 added this trouble would probably be eliminated. 



The experimental papers have not yet been tested on high-speed 

 presses, and this must be done before accurate knowledge of the value 

 of the several sheets can be had. 



However, after having obtained news paper of the quality of the 

 attached samples from hemlock, jack pine, and mixtures of these 

 woods without changing in any way present commercial practice, it 

 seems beyond doubt that these woods may be advantageously used 

 either singly or in various combinations, at least in the cheaper grades 

 of paper. 



TABLE 3. Strength, weight, and thickness tests on experimental papers. 



All of the above are averages of 10 determinations. 



SUMMARY OF DATA. 



Tables 4, 5, 6, 7, 8, and 9 show compilations of the data secured 

 during tests on hemlock, jack pine, and mixtures of these two woods 

 with spruce. The results of tests under many different conditions of 

 speed, pressure, and surface of stone are given. In a number of cases 

 the data on production and power consumption do not agree with that 

 taken at another time and under the same conditions of pressure, 



