Here's a Dorothy Sloan auction offering description for a pocket map 
version:

214. [POCKET MAP]. EPPINGER, J. & F[rancis] C. Baker. /Map of Texas 
Compiled from Surveys Recorded in the General Land Office/. N.p., 1852. 
_Pocket map_. Engraved map on onionskin paper, original full color, 
folded into 16mo, original brown cloth folder stamped in gilt and blind. 
75.7 x 60 cm (29-5/8 x 23-5/8 inches). Scale: 1 inch = approximately 20 
miles. Inset map: /Map of New Mexico, California, and Utah/. Pocket 
covers worn. Some old oxidation stains at left and right sides of map. 
Original color somewhat faded. Very rare, large-format pocket map of 
Texas. This map is actually more rare than the De Cordova.
         This map first came out in 1851, and was published again in 
1852 with only the date changed. Day, p. 56 (photostat only): "The map 
shows Texas and parts of Indian Territory, Arkansas, Louisiana, Mexico, 
and denotes counties, towns, roads, rivers, creeks, lakes, mountains, 
forts, location of Indian tribes, Indian villages, Chickasaw Depot, 
forested area, places and dates of battles of Mexican War." Taliaferro 
304 (photostat only): "Following the format established by Stephen F. 
Austin's map of 1830, this map shows Texas east of approximately the 
101st meridian. West Texas appears on a reduced scale in the inset. The 
1852 issue is evidently quite rare. It is not listed in Phillips, or 
Graff, and is not in Day (except in photostat). Phillips (/America/, p. 
44) lists only the 1851 issue."
/The Handbook of Texas Online /(Francis C. Baker): "Francis C. Baker 
(1821-?), newspaper editor and railroad promoter, was born in Indiana in 
1821.... [He] was called Dr. F. C. Baker by the time he became an editor 
of the Jefferson /Democrat/ at Jefferson, Texas, in 1848. In the same 
year he undertook a scientific exploration of Texas with J. Eppinger and 
J. D. Baker. In 1851 F. C. Baker and Eppinger compiled a pocket map of 
Texas."
         The inset map entitled /Map of New Mexico, California, and 
Utah/ shows the Transmississippi West from approximately the 101st 
meridian (not in Wheat). This important pocket map was one of the first 
Texas maps after De Cordova based on information compiled by the General 
Land Office of Texas. Shown are additional counties created after 1850. 
We locate only one other copy of this 1852 edition of the map.
($20,000-40,000)


          Joel Kovarsky


On 5/18/16 3:35 PM, Wagner, Leslie A wrote:
> And it appears I had a hand in cataloging that map during the digitization project wherein we provided 5,000 for UNT to digitize and upload to the Portal to Texas History. Nice to know it's increased in value.
>
> Leslie Wagner
> Metadata Archivist
> Access & Discovery
> University of Texas at Arlington Libraries
> 817-272-6209
> [log in to unmask]  
>
>
>
> -----Original Message-----
> From: Maps-L: Map Librarians, etc. [mailto:[log in to unmask]] On Behalf Of Angela R Cope
> Sent: Wednesday, May 18, 2016 11:38 AM
> To:[log in to unmask]
> Subject: Antiques Roadshow: GLO 1852 Texas Map
>
> And more on the famous map of Texas!
>
> -a-
>
> ________________________________________
> From: Discussion of Government Document Issues<[log in to unmask]>  on behalf of Hartman, Cathy<[log in to unmask]>
> Sent: Tuesday, May 17, 2016 5:28 PM
> To:[log in to unmask]
> Subject: Re: Antiques Roadshow: GLO 1852 Texas Map
>
> This appears to be the same map from the Portal to Texas History (from the collections of UT Arlington):
>
> Eppinger, J. Map of Texas., Map, 1852; (http://texashistory.unt.edu/ark:/67531/metapth231412/  : accessed May 17, 2016), University of North Texas Libraries, The Portal to Texas History,http://texashistory.unt.edu; crediting University of Texas at Arlington Library, Arlington, Texas.
>
> Cathy Hartman
> UNT Libraries (Retired)
> [log in to unmask]<mailto:[log in to unmask]>
>
>
> 17, 2016, at 1:10 PM, Angela R Cope <[log in to unmask]<mailto:[log in to unmask]>> wrote:
>
> This is not a GLO map but one compiled from the government land surveys but by Baker and Eppinger. Here is the link with a picture of the condition of the map (quite nice):
>
> http://www.pbs.org/wgbh/roadshow/archive/201306A08.html
>
>
> And Here is what the appraiser said about the map:
>
> APPRAISER:  "I see. It's an 1852 map, and it's one of the nicest and rarest Texas maps I've seen in a long time. It's in great condition. It only has a little bit of wear to it. And indeed, it's a valuable map. This map was published in 1851 by F.C. Baker and J. Eppinger. And this is the second edition from 1852 of the same map. Generally, these maps were printed in fewer than 1,500 copies and sold for not much money back then either: 50 cents or a dollar at the most. And this shows some counties that had been added since 1850. But in Texas history, it's considered one of the great rarities. One of the great things about this map is that it has an inset of New Mexico, California and Utah. It's quite accurate, and it shows San Francisco up here, but it doesn't really show Los Angeles down there."
>
>
>
>
> -Angie
>
> Angie Cope
> American Geographical Society Library
> UW Milwaukee Libraries
> 2311 E. Hartford Avenue
> Milwaukee, Wisconsin 53211