N Ew Woods for Paper Pulp Research in Forest Products by the Forest Service, U

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June 16, 1917 SCIENTIFIC AMERICAN 593 N ew Woods for Paper Pulp Research In Forest Products by the Forest Service, U. S. Department of Agriculture

By Dr. Otto Kress

THE results of scientific agriculture are popularly larger yields of pulp, of greater strength, in a shorter "fuzziness" of the finished sheet, and the introduction expressed by the phrase "making two blades grow time, and with less consumption of chemicals than with of moisture during the cooking period was found to in where one grew before," but with forest products the the standard method now used. Cooks were made on crease the yield of pulp 9 per cent. Comparative runs problem is slightly different. The aim is to make one thirteen different species of wood and excellent sheets were made by the kraft process on cleaned wood and on tree do what two did before. For example, lumbering were produced, particularly from spruce, Alpine fir, and uncleaned chips with 4 per cent bark, and also on clear, has made the heaviest drain upon the forests and in western yellow pine. Paper from western yellow pine longleaf pine bark. The chemical consumption by the this industry over two thirds of the material in the tested very high and was superior to any other kraft bark was about 39 per cent, based on the weight of the forest has been lost while putting the remainder into the laboratory has produced. A good kraft was also bark, and the product was of a shiny nature. Mills marketable form. The actual loss has not been so made from southern yellow pine. While there are a few pulping uncleaned wood should compare the extra cost great because the form it is in has naturally made the mills in the South making kraft wrapping paper from of barking to that of pulping unbarked wood. waste of little value under Utilization is, however, being ordinary conditions. By scien extended to include the bark. tific research, however, it is Spent hemlock bark gives prom proposed to develop uses and ise of being important indus markets for this waste, and the trially. This bark is now used Forest Products Laboratory at chiefly for fuel but the labora Madison, Wisconsin, was estab tory has found that it is pos lished by the Forest Service, sible to substitute it for as much U. S. Department of Agri as 30 per cent of the rag stock culture, to encourage research used in roofing felts. Over in the forest products industries. 200,000 tons of roofing felt are These industries employ over made annually and the basic a million wage earners, and their fiber material has been rags, products, including remanufac many of them imported. The tUl'e, are valued roughly at use of bark, if universally two billion dollars annually. adopted, should cut the cost of Investigations are made of manufacturing felts in this coun the physical and mechanical try a milliol', dollars annually, properties of wood, of methods and at the same time double for the protection of wood the value of the bark. against decay and fire, of the Waste bark is produced as a use of wood in the pulp and by-product from the barking paper and distillation indus of pulpwood preparatory to tries, and of the naval stores grinding or chipping, from the industry. The laboratory is tanning industry in the form of well equipped with apparatus spent tanbark, from the veneer for experiments on a semicom- Paper twine made out of sawmill waste industry, and from the lumber mercial scale, and ultimately ing of such woods as cypress a commercial demonstration is made with each problem sawmill waste, the bulk of such waste is being burned and redwood. The various barks can only be looked if experimental results warrant it. just to dispose of it. The United States produced in upon as fillers and will require the addition of longer and At this time the work on wood pulp is of special in 1912 nearly fifty million dollars' worth of wrapping stronger fibered stock. Uses that suggest themselves terest because of the acute paper situation. The paper, while several times this amount could be made for waste tanbark are the manufacture of indurated pressure of economic conditions is driving the American annually from the waste incident to the lumbering of fiber ware, wall paper, sheathing paper, deadening and manufacturer in those regions where the supp!y of yellow pine in the South. felts. Spruce and balsam bark might be used in the pulpwood is being exhausted across the border into the Kraft differs from other papers, in that it is much manufacture of wall board and the more fibrous barks, virgin forests of Canada. The United States already stronger, due to less severe action of the chemicals. such as redwood, might be used for insulating purposes. depends upon Canada for a third of her newsprint paper Large quantities of it are used for wrapping paper, A considerable number of small problems confronting either in the form of finished product or raw mate and it is particularly suitable for large envelopes. Spun small mills which are of general interest to the' industry rial, and indications are that if have been studied, For example, the United States is to retain samples of ground wood have preemmence in wood pulp been received covered with spots manufacture she must use her which on examination were wonderful western and Alaskan found to be a kind of mold resources. Tests by the labora which infected the pulp while tory have demonstrated the in storage, and therefore elim suitability for various grades inated the need of looking into of paper of no less than ten new any of the stages the pulp had or little used woods including gone through before reaching Engelmann spruce, lodgepole that point. Determinations of pine, white fir and other abund the exact species of wood are ant and cheap coniferous woods frequently made when samples of the Western States. Experi are submitted by various manu ment.al pulps from twenty facturers. four such we·ods were first taken By thus cooperating wIth the to a commercial paper mill and manufacturers the laboratory made into newsprint, which is able to concentrate on the waf' then used by the New York more important problems and Herald and the St. Louis Re assist in extending technical public in one of their daily knowledge of the industry. editions. The pressmen ex British and Russian Science pressed entire satisfaction with the manner in which these to Couperate papers ran through the presses. ACTIVE measures have been It was noted that paper from taken in Russia during the different woods showed a varia past year to bring about closer tion in color and a study was relations between the scientific undert.aken with the Depart men and organizations of that ment of Psychology, University country and those of Great of 'Wisconsin, to determine the Britain. Last October the Im effect of color on eye fatigue. Onion and coffee bags, matting and burlap made out of spun paper perial Academy of Sciences, in Slight variation in color is prob Petrograd, appointed a com ably of no real importance. It is doubtful that the paper products open up a large field for the use of kraft, mittee to push this undertaking. One result of the average reader has noticed any difference in the color Cut into strips, either with one side gummed and spread movement which will greatly interest the scientific world of his newspaper, which is now furnished in the naturai with a fine lint or used plain, it is run into a spinning in general was the constitution of a committee of special shade due to the present shortage of dyes. At least ten machine and twisted into threads. This thread is then ists, under the direction of the academy, charged with of the new woods were entirely satisfactory for news woven into such products as onion and coffee bags, editing two new scientific periodicals, which will present, print and our own forest resources have thus been matting, suitcases and bags, burlap, furniture resembling in French and Russian, a summary of current work by shown to be ample to meet the paper requirements of reed, coarse mattings, twine, etc. Russian savants. One periodical will be devoted to the the country. Studies are being made on the operative features of physicomathematical and the other to the biological The laboratory has also developed and applied for the chemical pulping processes to determine tht effect sciences. It is also proposed to have scientific attaches patents on a new method of cooking wood by the sulfate of varying concentrations, temperatures, pressures, and assigned to the RU3sian legations abroad, and to the process. (Such patents are dedicated to the free use of time of cooking, and also the effect of beating. Over British, French and other legations in Russia. The the public.) Wood cooked by this method has given cooking of soda pulp was found to be the cause of Academy proposes a congress to discuss this subject.