"THE DEMIJOHN
The word ‘demijohn’ appears in the literature beginning in the early 1700s. While large blown European bottles exist from as early as the 1400s, the word seems to have come from Persia at some later time. …
or Jemmy-john for demijohn, a large wicker-cased bottle, as though this word had not suffered enough already in its transition from Arabic damagan, itself taken from the Persian glass-making town of Damaghan. The Phililogy of Slang, Littell's Living Age, May 9, 1874.
Other sources trace the origin to a corruption of the French, dame-jeanne (lady Jane but the idea that the word came from a glass-making center makes sense. The characteristic that distinguishes a demijohn from any other bottle, aside from its size, is the fact that it was wicker covered. Early Egyptians covered their bottles with papyrus. This innovation may have spread from Egypt to Persia then to Europe and from there to America.
The earliest American references I could locate, though certainly not the first, were in The American Law Journal and Miscellaneous Repertory, Jan 6, 1809 which mentioned "bags of corks for demi-johns." and in The Balance and State Journal, September 29, 1809 which stated:
"Just Received, by the last arrivals from Europe and for sale on as reasonable terms as can be purchased in New-York, a very handsome assortment of DRY GOODS, adapted for the approaching season. ALSO Indigo, Pepper, Bottled Mustard by the box or dozen, Sherry Wine in qr. Casks, Maderia in Demijohns, for family use."
THE CARBOY
The terms demijohn and carboy were often used interchangeably. The distinction seems to be one of function more than form. A poem in The Port-Folio April 30, 1803 speaks of "Carboys Of Vitriolic Acid, For Old Bachelors" while the The Emporium of Arts & Sciences Philadelphia September 1, 1812 relates a story on ‘The Ignition of a Carboy of Aqua Fortis’ which burst into flame. When the burnt remains were examined, the writer referred to “...the remains of the straw and basket.” So like demijohns, carboys were wicker encased bottles. The two terms are differentiated only by their contents. Demijohns were for potable and non-corrosive liquids. Literature references to the word ‘Carboy’ indicate carboy contents to be strong chemicals - mostly acids: Saturday Evening Post Oct 13, 1821 mention of 50 carboys of Oil Vitriol and 10 carboys of Aqua fortis. Oil of Vitriol was sulfuric acid and Aqua fortis was nitric acid. One other reference was found to a carboy of muriatic acid (1833) now known as hydrochloric acid. Today manufacturers still use the term ‘carboy’ for large plastic acid containers.
The other difference found between demijohns and carboys was for 19th century shipping prices, with carboys being charged a higher rate, probably due to their hazardous contents. While carboys denote chemicals, demijohns have become closely associated with wine or spirits."
http://www.bottlebooks.com/demijohn/big_bottles_big_history_demijohn.htm