Discusses reasons for questioning the underlying assumptions of instruments designed to measure knowledge of the nature of science. Recommends that researchers recognize that conflicting models of science exist, and that each instrument related to these models must specify all philosophic assumptions. (MLH)

The procedure and sampler described permits detection of less than 50pg of one polychlorinated naphthalene (PCN) isomer. The method uses gas chromatography-mass spectrometry. The PCNs are collected on a glass fiber filter and two polyurethane foam plugs and extracted with toluene at 25 degrees Celsius. (BB)

This method of image enchancement and real-time imput of 3-D microscopic objects into an optical pattern recognition system is designed to identify and count diatoms as a means of water pollution assessment. The method consists of directing a low-power laser beam into a microscope to produce a coherent image of the specimen. (Author/BB)