NSTRUMENTATION
The atomic absorption assay was performed on a Perkin Elmer Model 380 spectrometer
with a silicon hollow cathode lamp and a 5-cm slot nitrous oxide-acetylene burner.
Samples were prepared with the aid of a Burrell wrist-action shaker and an IEC Clin-
ical © model 428 centrifuge, equipped with a 6 X 52-ml angle rotor and 50-ml shields.
Photos were taken on Polaroid Polapan Type-52 film, through the objective of a JEOL
T300 scanning electron microscope. Hair samples were mounted on an aluminum tab
with double-sided tape and then gold-sputtered for 50 seconds. The tab was then
mounted in the microscope and the samples viewed without tilting the stage. No dif-
ference in image resolution was detectable by rotating the angle of the stage. The
photos were taken at a magnification of 2000 x.