Images

A Portrait of Tsar Peter III and his wife, the future Catherine the Great, oil on canvas by Georg Christoph Grooth, c. 1745. Odesa Fine Arts Museum, Odesa, Ukraine.

Portrait of the Grand Duchess Ekaterina Alekseyevna (the future Catherine the Great) around the time of her wedding, oil on canvas by Georg Christoph Grooth, 1745. Hermitage Museum, Saint Petersburg. Scanned by Mrlopez2681 from the Sept...

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)

An infographic illustrating the succession of Roman rulers between 96 and 180 CE, known as the Five Good Emperors (a term unknown to the ancient Romans, coined by Nicolo Machiavelli in his 1531 manuscript Discourses on Livy and made widely...