But how old is the present form of these characters? According to Scaliger[79], they are of great antiquity, because they are to be found on very old gems and rings. If the ring No. 104 in Goræus be old and accurately delineated, this must indeed be true; for some of these characters may be very plainly distinguished on the beazel[80]. We are told by Wallerius that they were certainly used by the ancient Egyptians, because Democritus, who resided five years in Egypt, speaks of them in the plainest terms. I do not know whence Wallerius derived this information, but it proves nothing. He undoubtedly alludes to the laughing philosopher of Abdera, who lived about 450 years before our æra, but no authentic writings of his are now extant. Fabricius says that we have a Latin translation of a work of his, De Arte Sacra, Patavii, 1572, which, however, is certainly a production of much later times. I have it now before me from the library of our university; and I find that it is not the whole book, but only an abstract, and written in so extravagant a manner that the deception is not easily discovered. It contains chemical processes, but nothing of the characters of metals; which is the case also with the letters of Democritus, published by Lubbinus[81]. [By way of contrast to the seven metals with which the ancients were acquainted, we may enumerate those known at the present day. They are as follows:-- 1. Gold ☉ 2. Silver ☽ 3. Iron ♂ 4. Copper ♀ 5. Mercury ☿ 6. Lead ♄ 7. Tin ♃ 8. Antimony Basil Valentine 1490. 9. Bismuth Agricola 1530. 10. Zinc (Paracelsus?) 1530. 11. Arsenic } Brandt 1733. 12. Cobalt } 13. Platinum Wood 1741. 14. Nickel Cronstedt 1751. 15. Manganese Gahn 1774. 16. Tungsten D’Elhujart 1781. 17. Tellurium Müller 1782. 18. Molybdenum Hjelm 1782. 19. Uranium Klaproth 1789. 20. Titanium Gregor 1791. 21. Chromium Vauquelin 1797. 22. Columbium Hatchett 1802. 23. Palladium } Wollaston 1803. 24. Rhodium } 25. Iridium } Tennant 1803. 26. Osmium } 27. Cerium Hisinger 1804. 28. Potassium } 29. Sodium } 30. Barium } Davy 1807. 31. Strontium } 32. Calcium } 33. Cadmium Stromeyer 1818. 34. Lithium Arfwedson 1818. 35. Silicium } Berzelius 1824. 36. Zirconium } 37. Aluminum } 38. Glucinum } Wöhler 1828. 39. Yttrium } 40. Thorium Berzelius 1829. 41. Magnesium Bussy 1829. 42. Vanadium Sefström 1830. 43.