370 JOURNAL OF THE SOCIETY OF COSMETIC CHEMISTS of very thin (0.076 cm) circular templates of decreasing diameter. A plot of work values vs. circle diameter is extrapolated to zero work, to obtain the "maximum tress diam- eter." This parameter, hereinafter referred to as MTD, is a measure of the bulk of the hair assembly. The data presented here suggest that this parameter may be useful as an objective quantitative measurement of hair body. Dr. G. Blankenburg (6) has indicated that the German Woolresearch Institute has independently developed a similar method using this same principle. EXPERIMENTAL EQUIPMENT An Instron Tensile Tester, Model TM with Automatic Integrator, was used. Usual operating conditions were: chart l"/min., crosshead 2"/min., chart sensitivity 4 g full scale at 55 to 60% RH and 70øF. A support apparatus was constructed to mount to the Instron crosshead, Figure 1. This support holds removable 10.2 x 10.2 cm tern- Figure 1. Instron apparatus modified to measure the work to pull tresses through templates

HAIR BODY MEASUREMENT 371 plates, 0.76 mm thick, of butyrate, Figure 2. These templates contained centered circular holes with one hole per template, each hole from 10 to 76 mm diameter in 3 mm increments. The templates were specially made by Berol USA/Rapid Design, Burbank, California. Figure 2. Photograph of a typical template used in MTD measurement to assess hair body. METHOD TRESS PREPARATION Tresses are made by weighing 2 g or more of 8" DeMeo "blue string" dark brown hair and binding the root end with a rubber band. Each tress was shampooed with 10% of an anionic shampoo containing 18% trietha- nolammonium lauryl sulfate and 4% cocamide DEA and rinsed thoroughly with deion- ized water. Treatment with commercial body and cleaning shampoos was accomplished by shampooing the tress twice with one gram of test shampoo followed by a one-minute rinse with running water after each shampooing. Treatment with the experimental body product was one time only with one gram of the test product followed by a one-