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The Microscope – Volume 71, Third Quarter 2024

IN THIS ISSUE
On the cover
Photomicrograph of a bird feather using Rheinberg illumination combined with the Microlab Northwest LED ring light epi-illuminator. Rheinberg filter includes a yellow annular ring and blue central disk in conjunction with the purple LED from the ring light illuminator. (Photomicrograph courtesy of Heidie Crutcher)
Editorial | The Microscope
Gary J. LaughlinThe Microscope 71:3, p. ii, 2024https://doi.org/10.59082/IVYP1915 Excerpt: Words have meaning. For example, – the microscope – only two words that because we see them together nearly every day, may begin to lose, not necessarily their meaning, but rather, their importance, their significance, or their relevance. We as scientists, microscopists, if not microscope users, should be prepared to answer some basic questions about these two important words and what they mean to us and to our preferred instrument of choice, the microscope. The answers to which all can be discovered here in the pages of this journal with the anticipated if not expected title: The Microscope.
The Formation and Distinction of Erroneous Dispersion Staining Colors for Refractive Index Determination Using the Dispersion Staining Method
Shu-Chun SuThe Microscope 71:3, pp. 99–112, 2024https://doi.org/10.59082/BUGV6635 Abstract: The dispersion staining method is widely used to measure and determine the refractive index (RI) of non-opaque solid materials, especially asbestos minerals. A common problem with applying the central stop dispersion staining (CSDS) technique is the observance and appearance of a variety of CSDS colors for a given solid material’s actual refractive index possibly leading to incorrect refractive index determinations. This paper explores the formation of these erroneous dispersion-staining colors and proposes a solution to distinguish the actual CSDS colors from the erroneous dispersion staining colors, with the goal of preventing the misinterpretation of erroneous CSDS colors or the misuse of erroneous dispersion staining colors for the intended purpose of inaccurately reporting actual RI values.
Case Studies for the Use of Heavy Liquid Density Separation Prior to the Microscopical Examination of Talc Ore and Talcum Powders
Steven P. Compton and Matthew R. UnderwoodThe Microscope 71:3, pp. 113–126, 2024https://doi.org/10.59082/IATS5551 Abstract: The detection of asbestos fibers in talc and other milled mineral powders sometimes benefits from commonly utilized matrix reduction steps, such as ashing and acid washing. A less frequently applied, but proven and published sample reduction technique involves separating different density fractions of a mineral powder using aqueous “heavy” liquids. Two case studies involving samples of vintage talcum powder products and of processed talc ore provide information about the utility of such an approach when performed prior to microscopical examination.
Critical Focus | Microscopes and the Amazing School of the Future
Brian J. Ford The Microscope 71:3, pp. 127–138, 2024https://doi.org/10.59082/HWZZ7464 Excerpt: Where are the microscopes in our schools? Few schools have them, and occasionally teachers show students what miracles they reveal; but they are not a core feature of the curriculum. They should be. We know that children need to master the three Rs (reading, writing, ’rithmetic) but there should be a fourth. Reading, writing, ’rithmetic…, and rotifers. I’d prefer a more all-embracing term for microscopy, but couldn’t think of one starting with R. You might have a better proposal. Students would go to a pond in springtime and use a microscope to learn a dozen microbes. No watching videos here; it’s hands-on experience that the youngsters need. Everyone should understand life for themselves, and this is how we begin to make sense of the secrets of the living world. Most people wouldn’t know a living cell if they saw one. Knowing what life is like under the microscope will teach more about health, and hygiene, and nutrition, and the environment…, than any other single subject. It is the syllabus that is the problem. Education has never kept up with the realities of the outside world, so kids learn all about algebra but nothing about running a home. The principal purpose of learning is to acquire the skills you need to be a functioning adult, and that’s the one thing you never learn at school.
A New Approach to Optical Staining and Light Interaction Analysis Using a LED Ring Light Epi-Illuminator
Heidie Crutcher The Microscope 71:3, pp. 139–143, 2024 https://doi.org/10.59082/PZCL3480 Abstract: The author aims to explore practical applications in light microscopy using the pre-programmed colors in the Microlab Northwest LED ring light epi-illuminator; designs for which were previously published in this journal. By modifying a microscopy technique first introduced in 1896 by Julius Rheinberg, it was possible to analyze the light scattering, light reflection, and light refraction properties of various samples, including four microscopic objects: plant hairs, phytoliths, feathers, and sand. Each sample exhibits unique light interactions. Thermally modified calcium oxalate phytoliths demonstrate the potential for optical staining of objects as small as 5 μm, while plant hairs and bird feathers highlight thickness-dependent light scattering. Sand exhibits a combination of light reflection, light scattering, and light refraction phenomena.
Afterimage | Chicago Skyscraper Gorges
Florian Grosse — Berlin-Chemie AGThe Microscope 71:3, p. 144, 2024
Metformin hydrochloride, an antidiabetic drug substance recrystallized from solution as a thin film using the polarized light microscope, crossed polars. Selected as Most Unique Photomicrograph at the Inter/Micro 2024 Photomicrography Competition in Chicago.
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