488 ANNUAL REPORT SMITHSONIAN INSTITUTION, 1960 



The widespread adoption of the new laboratory tecliniques, both 

 by manufacturers and by merchants, was greatly accelerated, as the 

 numbers of laboratories and workers increased, by a second wave of 

 inventions, which for the most part had the effect of shortening the 

 time required to obtain the wanted results. Of these, one of tlie most 

 important was the Micronaire, an invaluable contribution of William 

 Sharrott Smith, one of the younger men who after a number of years 

 with Webb had left his organization and joined the staff of a labora- 

 tory newly established by the West Point Manufacturing Company. 

 Smith discovered that by measuring the flow of a current of air at 

 known pressure through a small sample of cotton (50 grams) confined 

 in a chamber of known volume, a reading could be obtained in a 

 moment's time upon a scale which gave an index, within limits, of 

 the average fiber fineness in combination with the average fiber ma- 

 turity of the cotton — an observation which up to that time could be 

 made accurately only by calculation from a laborious series of fiber 

 sortings, weighings, and microscopic evaluations. Smith's Micronaire 

 apparatus was developed through cooperation with the Sheffield 

 Corporation. 



Further refinement was later to be made in the widely used Micro- 

 naire fiber test, the index readings of which reflect without discrim- 

 ination the content of highly desirable fibers of fine caliber, normally 

 developed, and of flaccid, immature, and thin- walled fibers deleterious 

 to yam quality and spinning performance. Because low Micronaire 

 values are known generally to be influenced by abnormally liigh per- 

 centages of immature fibers, the Micronaire index alone is invaluable 

 to spinners in detecting bales in which the percentage of immature 

 fibers is greater than their work can tolerate. It remained for Samuel 

 T. Burley, Jr., a long-time and higlily perceptive worker in the re- 

 search program originated by Dr. Webb, to conceive a process in 

 which, by mercerizing the Micronaire sample with a caustic soda 

 solution after its first reading and subjecting it again to the Micro- 

 naire test, it becomes possible to read on a second scale an index figure 

 which permits an evaluation of cotton fineness and maturity in- 

 dependently of each other, and substantially explains the degree to 

 which fiber immaturity actually influenced the originally observed 

 Micronaire value. That is known as the Causticaire Method. To 

 establish the Causticaire Scale required meticulous calibration with 

 data laboriously gathered from weight-per-inch and maturity analy- 

 ses of a great number of cottons throughout the quality gamut. In 

 this phase of his Avork, Burley often sought statistical evaluations and 

 counsel of Webb, whose role as mentor to younger men was often to be 

 repeated. Burley was subsequently to be given charge of the devel- 

 opment and operation of Agriculture's new pilot plant at Clemson, 

 S.C., for special cotton processing and fiber-testing studies. 



