Contents: -- -Introduction; physical strength of nonfiction book papers, 19001949, Study I. (Study includes actual findings of the physical condition of 500 typical non-fiction books printed in the United States in the first five decades of this century; data shows a steady decline of strength with age.); Tables, Figure and Lists for study I; Stabilization of modern book papers, Study 2 (Method recommended to correct acidity in old paper is to take the books apart, soak each page overnight in a saturated solution of calcium and magnesium bicarbonate, dry and rebind); Tables and Figure for Study 2; Work in progress; Bibliography. (Colophon at end explains that this report is Printed by Whittet and Shepperson, Richmond, Virginia, on a stable and enduring text paper developed under a grant to the Virginia State Library by the Council on Library Resources, Incorporated, through the experimental work of W. J. Barrow and through trial runs made by the Herty Foundation, Savannah, Georgia. It is composed of well purified chemical wood fibers; one-third sulfate, one-third sulfite and one-third soda. It is filled with ten per cent clay and ten per cent calcium carbonate added in the beater. It is machine sized with Aquapel, a size compatible with alkalinity, that has been developed by the Hercules Powder Company, and it is surface sized with a seven per cent starch solution. The first commercial run was made by the standard paper Manufacturing Company and was distributed by B. W. Wilson Paper Company, both of Richmond, Virginia. The paper has the following properties: basis weight 60 lbs.; color cream; opacity 89; folds 407 in weak direction (M.I.T. 1/2 kg. tension); tear 79 grams in weak direction (Elmendorf) and pH 9.0 (cold extraction). It is estimated that after artificial aging for 36 days at 100°C, 40 per cent of the fold and 75 per cent of the tear will be retained thus giving a theoretically useful life of at least 300 years ). -- AATA