Even Panama Jack had access to ERB's classic novel A Princess of Mars

According to the December 18, 1918 (Vol. XII, No. 18) issue of The Panama Canal Record, the official publication of the Panama Canal that was published weekly by the United States government in Balboa Heights, Canal Zone, even Panama Jack had access to Edgar Rice Burroughs’ classic novel A Princess of Mars (1917):

The sale of books by the Commissary Division continues to meet with favor on the part of patrons, and sales have been uniformly good. With the approach of Christmas, and the appropriateness of books as gifts, it is believed that many will wish to take advantage of the large stock on hand, some of which has just been received. The following titles, while by no means representing a complete list of those on hand, present a good variety from which selections may be made for gifts [...]

In this connection, a requisition has recently been placed with the commissary purchasing agent for a further supply of books, embracing all that is new in fiction, humor, etc. The following are among the titles ordered:

The Red One, and Other Stories.................... Jack London
A Princess of Mars.......................... Edgar Rice Burroughs
The God of Mars............................. Edgar Rice Burroughs
A Daughter of the Land.................... Gene Stratum Porter
The Laughing Girl............................. Robert W. Chambers
Shavings....................................................... Jos. C. Lincoln
Ashton-Kirk, Criminologist.................... John T. Mclntyre
Josselyn's Wife........................................... Kathleen Norris
Firebrand Trevison.......................................... C. A. Seltzer
Treat'em Rough............................................. Ring Lardner
My Four Weeks in France............................ Ring Lardner
From Baseball to Bodies................................ H. C. Witwer
The Island Mystery.............................. G. A. Birmingham
The Clutch of Circumstance.......... Majorie Benton Cooke
The Money Maker...................................... Irving R. Allen
Gaslight Sonatas............................................ Fannie Hurst
The Cross of Fire................................ Robert G. Anderson
Virtuous Wives........................................... Owen Johnson
Dere Mable......................................................... E. Streeter
The House of Torchy....................................... Sewell Ford
The Valley of the Giants............................... Peter B. Kyne

Notice will be given through the columns of The Panama Canal Record when the above books are received, together with a short review which will serve as a guide to purchasers in making selections.

Apparently, regular shipments of books were distributed among commissaries at Ancon, Balboa, Cristobal, Pedro Miguel, and Gatun, and titles were priced at about a dollar.