The coverslip ensures both your specimen and the objective of the magnifying lens from harm. Dampness will demolish the seal around the edge of the focal point (lens) unless a focal point is uncommonly made to focus through water or oil. Numerous of the focal points are made with the refractive index of a coverslip figured into where their central point is, so indeed in the event that you fair need to damp mount something, you still require a coverslip on it. It too, keeps the specimen from drying out by anticipating dissipation when uncovered to the warm of the light on the scope.
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