DURABILITY AND STORAGE 341 in the stack. It is not advisable to use gas lighting in the stock rooms; apart from the risk of fire, the products of the combustion of gas have a deleterious effect on paper. BIBLIOGRAPHY 1. Proc. Tech. Sect. P.M.A., 1937, XVIII, Part IA: Report of Paper-Testing Committee. 2. Pons: Proc. Tech. Sect. P.M.A., 1931,12,91. 3. GOLDBERG: Joum. Soc. Chem. Ind., 1937,56,249 T. 4. HAMMONDS: Paper Trade Journal, 1936,103,32. 5. BEKK: Proc. Tech. Sect. P.M.A, 1935,16, i. 6. FAIRBROTHER: World's Paper Trade Review, 1937,58, T 538. 7. MEESE: Papier Fabr., 1937,35,177. 8. STRACHAN: Paper-Maker, 1937,93, T 549. 9. SCHULZE: Papier Fabr., 1937,35,219.