HEMP HUEDS AS PAPER-MAKING MATERIAL. 15 



Washing and hleacMng. — Washing and bleaching were performed 

 for the purpose of bleaching the brown-colored cooked stock to a 

 white product, since it was regarded as highly probable that the fiber 

 would be suitable for book-paper manufacture. The colored stock 

 was charged into a 400-pound beating and washing engine of regular 

 construction and washed about one hour, the cylinder washer being 

 covered with 60-niesh wire cloth in order to remove fine loose dirt 

 and chemical residues. The washer was then raised, the stock 

 heated by steam to about 40° C, and a solution of commercial 

 bleaching powder was added in the quantity judged to be necessary, 

 after which the stock was pumped to a large wooden tank, to remain 

 and bleach over night. If the stock was bleached sufiSciently white 

 it was drained and washed from bleach residues, and if not more 

 bleach was added until a good color was obtained. The bleaching 

 powder used was estimated to contain 35 per cent of available 

 chlorin, as this is the commercial practice, and the amount required 

 was calculated to the bone-dry weight of the unbleached stock. 

 More bleach is required for undercooked stock than for stock which 

 is properly cooked or overcooked; therefore, the percentage of 

 bleach required is an indication of the quality of the cooked stock. 

 Since bleaching is usually more expensive than cooking, it is desirable 

 to cook to such a degree that the consumption of bleach wUl be held 

 within certain limits, depending on the raw materials used and the 

 quahty of paper to be produced. In these tests it was desirable so to 

 cook the hurds that the consumption of bleach would not be over 

 about 10 per cent of the fiber. 



Furnishing. — Furnishing is the operation of charging the beating 

 engine with the desired kind or kinds of fiber in the proper proportion 

 and amount and the adding of such loading and sizing agents as may 

 be necessary. As shown in the record of results, the furnish in these 

 tests consisted of hurd stock alone and of various proportions of 

 hurds, sulphite fiber, and soda fiber. The percentages to be given in 

 the record of the furnishes refer to the percentage of the total fiber 

 furnish, and this likewise applies to the loading and sizing agents. 

 In case sulphite or soda fiber was used, the commercial product in 

 the dry state was charged into the beating engine and disintegrated, 

 after which the hurd stock was added in the wet condition. 



Beating. — Beating is that operation concerning which the paper 

 makers often say "there is where the paper is really made," and 

 although the statement may not be literally true it contains a great 

 deal of truth. It is the operation whereby the fibers are separated 

 from each other, reduced to the proper lengths, and put in such a 

 physical or chemical condition that they felt properly and form into a 

 satisfactory sheet. It is pro})ublo that the quality of the shoot 

 depends more upon the proper beater action than upon any other 

 single operation. The action consists in drawing a water suspension 

 of the fiber between two sets of rather blunt knives, one set being 



