IN A WORLD WITHOUT CASTINGS


Would Modern Medicine Be Where It Is Today?


Dutch cloth merchant Anton van


Leeuwenhoek (1632-1723) is considered the father of microscopy. He is reported to have made more than 500 microscopes, the first of which consisted of a brass plate with a skewer mounted on it to impale the object being examined and rotate it. It had a spherical lens mounted in the plate (the microscope was hand held in front of the eye) and a screw for adjusting the height of the object. It gave magnifications up to 270 diameters. He was one of the first people to discover cells, and in 1674 he be- came the first to see and describe bacteria. Te demand on supplies brought about


by World War I resulted in the stan- dardization of microscope parts. Most microscopes began to be made from cast iron with a blackened finish and a 23 mm diameter tube. Te heavy base supports the rest of the assembly, which can be tilted and reflects light up through the speci- men to the optical tube. Adjustment was accomplished by turning a knob to initiate a crank-and-lever motion. Modern electron microscopes achieve up to 200,000x magnification.


March 2013 MODERN CASTING | 23


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