An alternative to Darkfield Illumination is Oblique Illumination. Here the sample is illuminated by an oblique ray or rays of light, rather than a high-angle annulus of light. The effect is one of side illumination, and the generation of a pseudo-3D effect. Oblique illumination is most often employed in Stereo microscopy.
Oblique illumination condensers (Abbe Condenser) from a microscope by the English firm of Powell & Lealand (Microscope #150, Golub collection). This microscope is dated 1861.