Day 29: My little home botany lab is equipped with a variety of specialized tools, mostly the hand-held (and less expensive!) versions of mechanized professional devices. Some of them require an extra degree of skill in order to get good results, and that's particularly the case with the microtome. Small specimens must be embedded in paraffin before mounting in the jaws, but larger pieces such as a snapdragon stem can be used without additional preparation. A straight razor is drawn across the glass plate to level the material, and then by turning the dial on the base, the specimen may be advanced in increments of 0.01 mm (10 microns). A second slice with the razor will yield a section of tissue suitable for viewing under the microscope.
The implement with the gold handle is also a measuring device. It is called a "mini-tool" and the spade end is 5 mm. wide, with each millimeter marked off in 10 divisions. With its markings barely visible to the naked eye, this tiny "ruler" is placed under the microscope objective at lower powers to determine such things as cell length/width. For higher powers, a reticule and/or stage micrometer are required, but that's for another post. Scientists have the coolest toys!
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