Images

A 1780s oil-on-canvas portrait by Alexander Roslin of Empress Catherine II of Russia (1729-96). Catherine was formally crowned empress regent on 22 September 1762 and this portrait endorses her royal status, perhaps a welcome endorsement...

Portrait of Catherine II, oil on canvas by Alexey Antropov, 18th century. Art Gallery of Tver, Russia.

A pen and ink drawing by Robert Hooke (1635-1703) first published in his Micrographia in 1665. This page shows a bluefly seen under a microscope. (National Library of Wales)

A pen and ink drawing by Robert Hooke (1635-1703) and published in his Micrographia in 1665. This page shows frozen structures seen under a microscope. (National Library of Wales)

A microscope with boxfoot made by George Adams in 1738. Based on a model designed by Edward Culpeper (1670-1737). The concave mirror at the base illuminated the specimen better than a flat mirror. (Science Museum, London)

A model of the microscope created by Antonie van Leeuwenhoek (1632-1723). Made by the Boerhaave Museum, Leiden, 1983. The microscope used a glass bead as a magnifier, giving a much greater magnification than other types of lenses available...

The compound monocular microscope of Louis Pasteur (1822-1895). Made by Nachet et fils, 1861-70. (Science Museum, London)

This infographic illustrates the succession of Roman emperors from 96 to 180 CE, commonly referred to as the Five Good Emperors - Nerva, Trajan, Hadrian, Antoninus Pius, and Marcus Aurelius. This term, unknown to the Romans themselves, was...

An early 18th-century microscope designed and made by John Marshall. It is a compound microscope, that is, it uses three lenses. Made of brass, wood, and other materials. (Science Museum, London)

A map of the Moon's surface by Galileo (1564-1642), drawn using a telescope the astronomer had built himself. The uneven line of shadow aided Galileo in identifying the nature of the Moon's surface and the approximate size of its mountains...