The Microscope – Volume 72, First Quarter 2025
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On the cover
The Ewald sphere is a crucial element when considering diffraction. It is a geometric construction that represents the conditions for elastic scattering of waves by the crystal lattice. See Rigorous Adherence to Morphology, Elemental Composition, and Crystal Structure Criteria in TEM Asbestos Identification, page 9. (Courtesy of Shu-Chun Su)
Editorial | Atoms in the Atomic Age
Gary J. LaughlinThe Microscope 72:1, p. ii, 2025https://doi.org/10.59082/FVEK2132
Excerpt: Occasionally, I will find a book in our library to entertain myself (and my grandchildren) and recently rediscovered The Architecture of Molecules, a book published in 1964, written by chemist Linus Pauling and wonderfully illustrated by architect Roger Hayward. In the preface, Dr. Pauling opens by saying, “We are now living in the atomic age.” This statement made me stop and think about that period of history and the words “atomic age.”
Calcite and the Beginning of Optical Crystallography
Russ Crutcher and Heidie CrutcherThe Microscope 72:1, pp. 3–8, 2025https://doi.org/10.59082/LPAG6864
Abstract: An optical-quality calcite rhombohedron, Iceland spar, was a critical part of the development of optical crystallography. Today, it is a valuable tool for training future crystallographers and any person wishing to better understand the basics of polarized light microscopy. Thirty different observations can be made to demonstrate optical properties of crystals. With a little additional information about the ions that make up the crystal, those observations can identify their orientation in the crystal. A brief review of the history of the efforts to explain the puzzling double image seen when looking through a calcite rhombohedron is a nice introduction to optical crystallography.
Rigorous Adherence to Morphology, Elemental Composition, and Crystal Structure Criteria in TEM Asbestos Identification: Addressing the Deviation of Identification Criteria
Shu-Chun Su
The Microscope 72:1, pp. 9–19, 2025
https://doi.org/10.59082/LGCN9979
Abstract: The correct and accurate analysis of asbestos carries profound implications for public health, environmental safety, regulatory compliance, and financial liability. Regulatory agencies such as the U.S. Environmental Protection Agency (EPA) and the Occupational Safety and Health Administration (OSHA) mandate standardized test methods for identifying asbestos in bulk materials, air samples, and building components. Despite these established protocols, deviations from scientifically rigorous identification criteria can result in diagnostic errors with far-reaching consequences for human safety and institutional trust.
Two primary analytical techniques are employed in asbestos analysis: polarized light microscopy (PLM) and transmission electron microscopy (TEM). PLM is widely used for its cost-effectiveness and suitability for bulk material analysis. However, TEM provides superior spatial resolution and is essential in high-stakes scenarios, such as the detection of low-concentration airborne fibers that are less than 10 nm in width and regulatory compliance assessments. TEM’s ability to resolve and unambiguously identify ultrafine structures makes it indispensable when sensitivity and specificity are paramount.
The Microscope Past: 50 Years Ago | A Short History of the American Microscope
Donald L. Padgitt
The Microscope 72:1, pp. 20–30, 2025
Originally published in The Microscope, Volume 23, Third Quarter, pp. 165–175, 1975.
Abstract: Unlike the well-documented accounts of European microscopes, the history of the American microscopes has been almost totally neglected. The first U.S. manufacturer was Charles A. Spencer who began in 1838. He was soon follwed by the Grunow brothers, Zentmayer, Tolles, Bulloch, McIntosh, Bausch, Lomb, and many others. Economic and other difficulties in Europe during the 19th Century led to emigration of many instrument makers to the U.S. By 1880, there were 20 separate companies making microscopes in the U.S. However, the number swiftly decreased and by 1900, there were only three — Bausch & Lomb, the Spencer Lens Company, and the about to fail James W. Queen & Company.
Critical Focus | Tomorrow's Infections Today
Brian J. Ford
The Microscope 72:1, pp. 31–45, 2025https://doi.org/10.59082/NDQL2117
Excerpt: You might think of the sun-drenched Atlantic Boulevard in Banjul, Gambia, as a carefree haven of leisure. Not me. This vibrant West African locale evokes a far more meaningful association: the headquarters of the Medical Research Council (MRC) where, some four decades ago, I encountered the unforgettable human toll of diseases that we had relegated to the margins of Western awareness. There crouched a village elder, his cheeks etched with the cruel scars of smallpox; a youth robbed of sight by onchocerciasis, river blindness; a bright young mother, her vision extinguished by trachoma — these were not mere case studies but living testimony to the relentless scourge of tropical infections. I was introduced to patients grappling with bilharzia, and the grotesque distortions of elephantiasis.
In Memoriam | John A. Reffner (1935-2025)
The Microscope 72:1, pp. 47, 2025
Excerpt: John Albert Reffner, Ph.D., a highly influential scientist and educator in the fields of analytical and forensic science, died on March 21, 2025, in Dover, New Hampshire. He was 90 years old. Born on January 5, 1935, in Akron, Ohio, Dr. Reffner was the son of John Patrick Reffner and Marie Reffner (née Zimmerman). He earned a Bachelor of Science degree in Chemistry from Akron City College and later completed a Ph.D. in Chemistry at the University of Connecticut.
Reffner had a distinguished and varied career that spanned academia, industry, and forensic practice. His work focused on microscopy, microchemical analysis, spectroscopy, and forensic trace evidence analysis—fields in which he made enduring contributions. He played a leading role in the development of infrared microspectroscopy, creating instrumentation and methods that remain central to forensic and materials analysis.
Afterimage | MicroComet
Kelly M. Brinsko Beckert — Microtrace LLCThe Microscope 72:1, p. 48, 2025
Pigment Red 101 mounted in Cargille 1.66 and viewed in oblique illumination; original field of view is approximately 250μm wide.
Pigment Red 101 mounted in Cargille 1.66 and viewed in oblique illumination; original field of view is approximately 250μm wide.
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