#State highway numbers in mapublisher code

Some, but not all, Diversified maps contianed a three or four digit date code. The following information was provided by Jim Wakefield:

Use the link above to connect to a site at Michigan State University to learn more about dating Clason maps. Instead, various elements of the maps changed over time. Clason maps are notorious for having no date information. Clason Road MapsĬlason Map Company was a map publisher in Denver, Colorado that published the first road atlas of the U.S. To obtain the publication date on maps using the Buddhist calendar (used, for example, in Thailand), subtract 542 from the date shown on the map.Ģ519 = 1977 California State Automobile Associationġ911-1914 681 Market (Monandock Bldg.), San Franciscoĥ26 = 1925 (Reverse first 2 digits for year)Īfter 1965 dates expressed as 4-66 = 1966, 6-68 = 1968. 12, 1954 (date + last two digits of year reversed + month )Īfter this date they seem to use more standard dating, e.g., 9-67 = 1967. 15 1957 (date + last two digits of year reversed + month )ġ24511 = Nov. Maps from the 1930s will often have three-digit codes containing just the month and last two digits of the year, generally in that order 336 = March 1936, for example.ġ5752 = Feb. The codes are generally publication dates jumbled in a certain, consistent way that are often preceded by the letter C, although this is not always the case.

#State highway numbers in mapublisher code

The code will contain four, five or six digits, depending on the month and date. (Source: David Cobb, Harvard Map Collection) Automobile Club of Southern Californiaīased on an e-mail exchange between Louise Ratliff and Morgan Yates. Do not confuse with the stock number, which is also in the same vicinity. Take the last two digits of the last four numbers and invert them, e.g., 3680 1209R = 1990. Arrow Map IncorporatedĪ number which often appears on the panel or in the margin of a map. Originally compiled by Linda Zellmer, based on a document developed by Phil Hoehn.