A microtome is similar to a deli meat slicer except that what it slices, human or animal tissue, is smaller in scale and not usually for consumption. Microtomes are important because they allow researchers to study the effects of different treatments on many tiny sections of tissue without having to resort to manipulating whole organs or mammalia.
Antiquated microtomes used a bulky and heavy semi-permanent blade. For safety purposes, most modern research facilities now use a lighter and thinner disposable blade. Even though both types of blades are equally sharp, the modern blade will not cut as deep if dropped when handling.
A mircotome usually slices paraffin-embedded tissue blocks into sections five microns thick. Wax helps stabilize the tissue to prevent it from collapsing and deforming when sliced. Once a wax-embedded tissue block is secured in the microtome, one dial moves the block perpendicularly closer to the blade. When the block is flush with the blade, another dial brings the block down onto the blade and inches it forward the set amount of microns with each turn. After a few turns, the result is a series of tissue sections, equal in thickness to be mounted onto slides.