FOEESTEY. 443 



Wood-using' industries and National Forests of Arkansas ( U. S. Dept. 

 Agr., Forest Serv. Bui. 106, pp. J/O). — This is a 2-part bulletin dealing with the 

 forest products and resources of Arkansas. 



Part I. Uses and supply of wood in Arkansas, J. T. Harris and H. Maxwell 

 (pp. 7-26). — This comprises a statistical account of that part of the sawmill 

 output which passes through further processes of manufacture in the State. 

 Tabular data are given showing the amount of such wood consumed annually 

 in Arkansas by species and industries, together with the cost and the per- 

 centage grown in and out of the State. The various woods included are briefly 

 described. 



Part II. Timher resources of the 'Sation<il Forests in Arkansas, F. Kiefer 

 (pp. 27-36). — This describes the various kinds of timber on the National Forests 

 and the means of purchasing it. 



Grades and specifications of rough stock and squares employed in making 

 special hardwood products for factory use, together with a summary of uses of 

 wood by Arkansas manufacturers are appended to the bulletin. 



Forest products of Canada, 1911. — Pulpwood, H. R. MacMillan, E. G. 

 McDouGALL, and W. G. H. Boyce {Dept. Int. Canada, Forestry Branch Bui. 30, 

 1912, pp. 17, figs. 3). — A statistical accoimt of the quantity and value of the 

 pulp wood produced in Canada, reported by species, Provinces, and processes. 

 Data are also given showing the pulp exported from the Dominion, together 

 with the pulp wood exported from the various Provinces in a manufactured 

 state. The 54 firms reporting used 672,288 cords in 1911 and 847,939 cords were 

 .exported in the raw state. 



Strength tefets of cross-arms, T. R. C. Wilson (17. S. Dept. Agr., Forest 

 Sere. Circ. 20 J/, pp. 15, figs. 2). — ^This circular describes tests of Douglas fir, 

 shortleaf pine, longleaf pine, and southern white cedar cross-arms, conducted 

 at the Forest Products Laboratory, Madison, Wis, 



The average maximum load borne by the various species and grades ranged 

 from 10,180 lbs. for longleaf pine with 75 per cent heartwood to 5,200 lbs. for 

 white cedar, the weakest wood used. Inasmuch as the poles have not with- 

 stood an average side pull of much more than 3,000 lbs., all of the woods tested 

 are considered sufficiently strong to be used for cross-arms. 



The preservation of raine timbers, E. W. Peters (U. S. Dept. Agr., Forest 

 Serv. Bui. 107, pp. 27, pis. J/, figs. 7). — Experiments conducted cooperatively by 

 the Forest Service and various mining companies throughout the United States 

 to secure authentic data on the efficiency of various methods of preserving mine 

 timbers from decay, in continuation of previous work (E. S. R., 19. p. 545), are 

 here reported. The work is discussed under the general headings of agencies 

 destructive to mine timbers, practical methods of increasing the durability of 

 timber, results of experimental treatments, cost of treatment, durability of 

 treated timbers, economy in the use of treated timber, and the avoidance of 

 waste. Analyses of presen-atives are appended. 



Decny was found to be the agency most destructive to timber used in mines. 

 Although this may often be retarded by peeling and seasoning, treatment with 

 a suitable preservative is more effective. Mine timbers impregnated with zinc 

 chlorid and creosote oils have shown the best results. Green, unpeeled, and 

 untreated loblolly pine gangway sets lasted less than IJ years. Brush treat- 

 ments with creosote and carbolineum increased the average life about 3 or 4 

 years, while impregnation treatments with zinc chlorid and creosote left from 

 70 to 90 per cent of the timbers sound at the end of 4 years. Either the brush 

 treatment, the open tank process, or the pressure process may be used in treat- 

 ing mine timbers, the method employed depending on the amount of material to 

 be treated. 



