New York correspondent Proteus on departure of "our own Melville"

Augustus Kinsley Gardner

Image Credit:  B012640 Portraits, Images from the History of Medicine

Who's Proteus? Looks to me like Melville's NY friend Augustus Kinsley Gardner (1821-1876), son of the editor of the Newark Daily Advertiser. The Duyckincks in their Cyclopaedia of American Literature name the Advertiser as one venue favored by Gardner, along with the Literary World, New World, and Knickerbocker. Several contributions by Proteus deal knowledgeably with the profession of medicine. Gardner's absorbing interest in his professional life and duties as a physician would explain the abbreviated career of Proteus as NY correspondent. Letters from Proteus appeared in the Advertiser from 1850 to 1854, the bulk in 1850-1851.
Aha! According to the biographical sketch by Samuel W Francis in the 1866 Medical and Surgical Reporter Gardner

"Contributed for years an average of many columns a week for the Newark Daily Advertiser."

Gardner's 1848 book Old Wine in New Bottles is compiled from letters to the editor of the Newark Daily Advertiser, signed "A. K. G."

Augustus K. Gardner was also the NY correspondent of New Orleans newspapers including the Commercial Bulletin, which in November 1854 printed Gardner's description of Melville at social gatherings as

 "taciturn, but genial, and when warmed-up capitally racy and pungent..."
(as quoted in Hershel Parker's Melville Biography: An Inside Narrative (Northwestern University Press, 2012) on pages 162-3.

From the Newark, New Jersey Daily Advertiser, Wednesday evening, November 20, 1850:

NEW YORK, Nov. 18

DEAR DAILY—Although as ever before, I write you from New York, Dr. Holmes has taught us that it is not from the metropolis. New York will not be in his opinion considered such, until

—Our first scholars are content to dwell
Where their own printers teach them how to spell.

This state seems impossible to be attained, for our men of letters seems [sic] to avoid cities.  Recently, Professor Longfellow has bought a farm at Stockbridge, Hawthorne another at Lenox, Mass., and our own Melville has deserted the birth-place of himself and his ancestors, and to the Berkshire hills has hied away to bury his genial humor, his fine understanding, but not, I trust, our friendship. Why these men should feel so ambitious of producing a cabbage or a pumpkin, I cannot tell. Perhaps it is their design to devote themselves to the philanthropic purpose of investigating the cause of the potato rot. Possibly the Bostonians have caught the chicken or pear fever which rages epidemically in that city....

[letter concludes with a plug for the new book by Cornelius Mathews]

…A work, issuing from the press, called Chanticleer, a national thanksgiving book, is recommended to precede the turkey and plum pudding era. The anonymous author will probably prove to be a well-known clever writer, who always commands the public attention.
PROTEUS.

Related posts:

• Review of Melville's Pierre in the Newark Daily Advertiser

• More reviews in the Newark Daily Advertiser