vi on geometric probability is included, students can be expected to create a few simple programs like those shown, but for other geometries. I am indebted to Tom Hare for critical reviews of the material and an endless enthusiasm to debate and derive stereological relationships; to John Matzka at Plenum Press for patiently instructing me in the intricacies of typesetting; to Chris Russ for helping to program many of these measurement techniques; and especially to Helen Adams, both for her patience with my creative fever to write yet another book, and for pointing out that the title, which I had intended to contrast to "theoretical stereology," can also be understood as the antonym of "impractical stereology." John C. Russ Raleigh, NC July, 1986 Chapter 1: Statistics 1 Accuracy and precision 1 The mean and standard deviation 5 Distributions 7 Comparison 13 Correlation 18 Nonlinear fitting 19 Chapter 2: Image Types 23 Planar sections 23 Projected images 25 Finite sections 28 Space-filling structures and dispersed phases 29 Types of images and contrast mechanisms 31 Sampling 32 Chapter 3: Manual Methods 35 Volume fraction 35 Surface density 38 Contiguity 41 Mean intercept length 42 Line density 43 Grain size determination 55 Curvature 48 Reticles to aid counting 49 Magnification and units 51 Chapter4: Size Distributions 53 Intercept length in spheres 53 Nonspherical shapes 57 Corrections for finite section thickness 59 Lamellae 61 Measurement of profile size 62 Nonspherical particles 69 vii Contents viii Chapter 5: Computer Metlwds 73