Robertus Keuchenius

Portrait of Frederick Spanheim II Robertus Keuchenius

Illustration of Scientist Robert Koch Working in Laboratory Anonymous

Gustav Robert Kirchhoff Anonymous

Portrait of Robert Junius Arnoldus Montanus

Mucius Scaevola before Porsenna, 1630s. Peter Paul Rubens

Robert the Bruce. Robert I (1274 – 1329) Anonymous

Thales of Miletus Nicolaes de Clerck

Robert Koch Anonymous

Robert Koch (1843-1910). Engraving. Colored. Anonymous

Mucius Scaevola before Porsenna, 1533 Anonymous

Plate with portrait preacher Robertus Junius Anonymous

Friedrich August Kekule von Stradonitz, German organic chemist, c1885 Unknown

Engraving of Robert Koch in his Laboratory Anonymous

Portrait of Peter Bortius, Reynier Blokhuysen J.D.F. Alphenus

Rhacodactylus ciliatus (eyelash gecko) Anonymous

Cecrops' Daughters Finding Erichtonius, c.1632 Peter Paul Rubens

Letter from Caleb Cheeshahteaumauk to Robert Boyle Caleb Cheeshahteaumauk

Portrait of Casparus Keidtwerdius Joannes Meyssens

The Finding of Erichthonius, 1632-33 Peter Paul Rubens

Gustav Robert Kirchhoff, German physicist, 1873 Unknown

Robert Bunsen, German chemist, 1850s C Cook

Portrait Engraving of Robert Mills Anonymous

The Death of Decius Mus, 1616-1617 Anonymous

Gustav Kirchhoff, Robert Bunsen and Henry Roscoe, scientists, c1860 Unknown

Robert Smythe Hichens, English journalist and novelist RA Reaks

Gustav Robert Kirchhoff, German physicist, 1876 Unknown

Mucius Scaevola Thrusting His Right Hand into the Flames before Lars Porsenna Master from Konstanz

Portrait of Robert Browning Anonymous

Robert Schumann 1853 Jean Joseph Bonaventure Laurens

General Robert E. Lee Engraving O'Neill

Portrait of Robert Wilhelm Bunsen Anonymous

Robert Koch Anonymous

Mucius Scaevola Confronting King Porsenna Bernardo Cavallino

Johannes Hevelius, German astronomer, 1673 Unknown

Rubens Peale with a Geranium, 1801 Rembrandt Peale

Archelaus, son of Herod, kneels before Caesar Augustus in Rome Pieter Mortier