The David Oscarson Lewis and Clark pens (www.davidoscarson.com) commemorate the duo’s expedition to the Louisiana Territory, which began in 1804 from St. Louis, the home of the pen-making company. The instruments’ designs incorporate an enamel-on-etched-metal guilloche that the company employs on all its pens. The Meriwether Lewis pen is red and gold with engravings of a compass rose on the barrel and Lewis’ signature on the cap. The William Clark pen is blue and silver, has a feather-shaped clip, and bears Clark’s signature on the cap. Each is made of sterling silver and limited to 100 examples. The fountain-pen versions are $4,900 apiece, and the roller-ball pens are $4,700.