"==Raw Material==

Etymology [will source later with OED]:
God name Mercury, from merx (""merchandise""). The name of the god comes from the same root as merchandise, market and mercantile.
Still need citation supporting discussion of this point in context.

Reference to Caduceus in Homer, Odyssey, V, 47-48

William K. Emerson, Encyclopedia of United States Army Insignia and Uniforms, University of Oklahoma Press, 1996, pp 181-182

""The Medical Department adopted a 1-inch-high gilt caduceus […] as its insignia in 1902. For the service uniform, officers wore the device in bronze […]. The caduceus, two serpents intertwined on a winged staff, was carried by Mercury, the god of commerce. Shortly after the surgeon general announced the caduceus as the medical symbol, critics said it was not appropriate, even though the caduceus had been used intermittently as various US Army insignia, starting with the chevrons for hospital stewards in 1851. The debate was important because it was apparent to all of the officers that the insignia was to become the device for the expanding Medical Department. The critics were unhappy with the caduceus as the medical insignia, and they stated that the single serpent looped about a staff was properly associated with Aesculapius, the Greek god of healing.

""The Army and Navy Register of 28 June 1902 noted the argument about the appropriate insignia. Giving the badge an unusual interpretation, the editor wrote of the caduceus: ""The rod represents power, the serpents stand for wisdom and the two wings imply dilligence and activity, qualities which are undoubtedly possessed by our Medical officers. The design, however, does not lend itself easily to a Corps emblem."" The dispute over the appropriateness of a caduceus continued for many years but never flared into a raging controversy.

[…] [Lengthy quote from old journal here, defending caduceus as a sign of non-combatants used to establish neutrality, and hence appropriate for non-combatants on the field. The article in defense of the caduceus states that it was chosen for neutrality, not medicine, and points out that the majority of the medical corps personnel are not even doctors.]

""The army influence in selecting the caduceus carried over to civilian physicians in the early 20th century, and many civilian medical personnel still use the caduceus as a symbol. Since World War II, many doctors have begun to display the Aesculapian staff. When the U.S. Air Force created a new medical insignia, it adopted the staff of Aesculapius, with a single serpent, as the device for medical personnel.""

A.H. Burkitt, ""On Tradesmen's Signs of London"" in: Journal of the British Archaeological Association, Volume 9, London, 1854,  pp 40-59

Article discusses tradesmen's signs in London that have for the most part fallen into disuse. Author discusses signs in use prior to the mid-18th century.

""Of the heathen deities and their attributes we find Mercury, or his caduceus, appropriate in trade, as indicating expedition [travel for the purpose of business]. Esculapius, his Serpent and staff, or his cock, for professors of the healing art […]""

Leslie S. Wilson, The Serpent Symbol in the Ancient Near East, 2001
Can't view this title, but it appears to deal with the putative babylonian origins of the caduceus in one section. Might use to balance against Frothingham/Ward claims.

Mark P. O. Morford, Robert J. Lenardon, Classical Mythology, 2007

""Some are outraged that the caduceus as a symbol of commerce and even worse should be associated with medicine. (Hermes was also a god of dishonest eloquence and thievery.) Others suggest that Hermes' caduceus may today be as appropriate an emblem for medicine as the staff of Asclepius. After all, the important business of medicine grows ever more complex, with advertising essential for competitive marketing. So one medical doctor, Glenn W. Geelhoed, poses the dilemma: ""Each of us physicians may choose what the profession should mean, and [between two serpent symbols representing very competitive ideals] adopt a symbol that is appropriate to…"" [Can't get page number or rest of quote through Google, page number also needed].

Luke Van Orden, MD, Where Have All The Healer's Gone?: A Doctor's Recovery Journey, Writers Advantage, 2002, p 129

""The caduceus has been the official emblem of medicine for four centuries or more. For the ancient Greeks, the winged staff with two serpents entwined was the symbol of Hermes, messenger of the gods and conductor of souls to Hades. Hermes was also the god of travelers, merchants, music, luck, eloquence, cheats and thieves. The earlier Babylonians regarded serpent