72'2 MISCELLANEOUS. [Mar. 



one-half as much more, if not double, the price it is to-day. The 

 woods most suitable for pulp-makiug are spruce, balsam, poplar, and 

 basswood (lime), the two former being more refractory to reduce 

 than the latter. Birch and beech are also used, but not nearly to 

 such an extent as the other woods mentioned. There are two 

 processes by which wood fibre is reduced to pulp, the mechanical 

 and the chemical. The mechanical process consists in grinding the 

 wood, which is cut into pieces about twelve inches long by four 

 inches square, and placed in small boxes on a machine, where, by 

 means of screws and hydraulic pressure, the wood is kept against 

 the edge of a broad grinding-stone rapidly revolving. "Water is 

 supplied freely to facilitate the grinding and to wash away the pulp 

 into receiving vessels, whence it is taken to be dried, and, if neces- 

 sary, bleached. The same work is accomplished also by grinding 

 with emery wheels. After the wood pulp leaves the grindstone, it 

 is manipulated so as to get rid of the coarse fibres of wood or 

 slivers that may be in it. After which it is run over what is called 

 in the trade a " wet machine " into thick sheets, which are then 

 bundled up and shipped to the paper-makers. The chemical process 

 requires a large investment of capital and great skill and experience 

 to make a good article. The wood is cut into chips diagonally 

 about three-eighths of an inch thick, thus preserving the fibre. 

 These are placed in a boiler with strong caustic liquor, closed 

 tightly, and boiled, according to the wood used, at a pressure of 

 from 90 to 120 lbs. of steam, for from eight to twelve hours. 

 When properly cooked, the steam is blown off, and the boiler 

 emptied into a drainer with a perforated bottom, which allows the 

 liquor to run into the tanks below, after which the pulp is carefully 

 washed, to carry off all trace of alkali ; and the liquor, after being 

 passed through a " recovery furnace," leaves a black soda ash wliich 

 is as good as new for working again. The paper-maker mixes the 

 wood pulp with rag pulp in a proportion of 40 to 60 per cent., 

 according to the standard and quality of papers required. 



Utilization of Waste Wood. — In the course of a lecture on 

 forestry, recently delivered at Coniston, Mr. J. Eobinson remarked that 

 the Exhibition of Forestry in Edinburgh in 1884 brought to light 

 an industry which was hardly known in England, except by its 

 results, and that was the manufacture of paper pulp from the 

 thinnings, etc. of trees. No less than fourteen of such manufacturers 

 •were grouped side by side at that Exhibition, and yet, so little does 

 one part of the world know about the doings of the other part of it, 

 that each of those pulp makers had till then apparently cherished 

 the notion that paper pulp making from wood was an industry that 

 was peculiarly his own ; and some of these Continental pulp makers 



