EMPLOYMENT CONTRACTS 101 compounded by the natural and continuing interest of the public which requires workable employee-employer relationships as well as individual freedom from unreasonable contractual restraints. So long as tech- nological change requires increased specialization by employees, the problems of employment contracts and adverse employees will inevitably become more acute. The number of controversies, however, may be limited by informed employers and employees who honestly seek to avoid conflicts over employment contracts. (Received September 11, 1965) (13) REFERENCES (1) Chem. Eng. News, 43, 81 (1965). (2) The Practical Lawyer, 9, 77 (1963). (3) See, for example, the holding of Spiselman vs. Rabinowitz, 270 App. Div. 548, 61 N.Y. S. 2d 138, 69 USPQ 192 (1946). (4) Sternberg vs. O'Brien, 48 N.J. Eq. 370 22A. 348. (5) See, for example, Driver vs. Smith, 89 N.J. Eq. 339 104 A. 717. (6) Restatement of Torts, 4, Sec. 757. (7) See, for example, Mycalex Corp. of America vs. Pemco Corp., 159 F. 2d 907, 72 USPQ 290 (1947) and cases cited therein. (8) Ridsdale Ellis, Trade Secrets, Baker, Voorhis & Co., Inc., New York (1953). (9) Restatement of Torts, 4, Sec. 757 b. (10) Eastman Kodak Co. vs. Powers Fihn Products, Inc., 189 App. Div. 556 170 N.Y. S. 325 (1919). (ll) E. I. du Pont de Nemours & Co. rs. American Potash & Chemical Corp. et al., 141 USPQ 447 (1964). (12) B. F. Goodrich Co. rs. Woh]gemuth, 137 USPQ 389 and on appeal at 137 USP• 392 (1963). New York Penal Law 1296 (4) by amend•nent effective July 1, 1964.

J. Soc. Cosmetic Chemists, 17, 103-114 (1966) Water Vapor Sorption and Potential of Starch Grains Suction F. EL-KHAWAS, M. Pharm., R. TAWASHI, Ph.D., and H. VON CZETSCH LINDENWALD, Ph.D.* Synopsis--The influence of water vapor sorption on the particle characteristics of potato, corn, and wheat starch is evaluated critically. The suction potential of the starch grains in a packed column is studied in both the presence and the absence of colloidal silica. The re- sults of these experiments lead to the conclusion that the suction potential and the rate of linear diffusion are closely related to the amount of silica dispersed in the powder bed. INTRODUCTION In different industries, particular attention has been given to vapor sorption and its influence on the properties of particulate ma- terials (1-4). Millet and Parisot (5) reported that the frictional and wear phenomena of graphite and carbon are related to their surface sorption properties. Ulmann (6) reported that the type of water present in potato starch, either in bound or adsorbed state, can be studied by the slow reduction in weight by means of infrared radiation. Dumonskii and Nekrgach (7) found a quantitative correlation between the amount of combined water and the heat of wetting evolved from starches. In a previous communication (8) it was shown that the bulk volume, frictional properties, and size distribution of cornstarch were markedly influenced by humidity. The intimate mixing of cornstarch with 0.5% hydrophobic silica reduced the interparticle friction to a definite value which remained constant at all degrees of humidity. The purpose of the present study is to evaluate the process of water vapor sorption and the suction potential in different starches, with the * Alexandria University, Department of Pharmaceutical Technology, Alexandria, Egypt. 103