Hooke's microscope

Hooke's Microscope

    Note the improvement over Spallanzani's instrument of a generation earlier. Illumination is by means of a candle flame reflected by a concave mirror (K) through a water-filled glass ball at left (C) that cools & focuses light at the point of observation (M), where the specimen is held by a clip (I). Focusing is done by adjusting a screw (G), which allows finer adjustments than in the earlier instrument. The optical system remains crude.

Figure © 1963 Gordon Ratray Taylor; Text commentary © 2022 Steven M Carr