Although the microscope was invented in the 1600s, it was not routinely used until the early 1800s, when new theories argued that all living matter was composed of tiny units called cells. The burgeoning interest in microscopy coincided with the invention of photography, which offered a promising alternative to drawing scientific observations by hand.

Bertsch, an amateur photographer, devoted himself for fifteen years to the significant technical challenges of photomicrography, making many innovations. His goal was to produce a photographic atlas of the animal and vegetable kingdom that both scientists and students could use as a reference. Bertsch’s photographs depict not only cells but also common pests such as this scabies mite, whose prickly skin and spiky legs, magnified to monstrous size, provoke a visceral response.