The History of a Rock Island Arsenal Globe
This post explores the history of a large spherical globe with only latitude and longitude lines in the collections of the Geography & Map Division.

Of all the globes in the Geography & Map Division’s collections, there is one that has always caught my eye: an impossibly heavy, large silver globe tucked away in our stacks, that stands without any depiction of the earth’s physical features at all. The large silver orb instead displays only a coordinate system grid composed of unlabeled latitude and longitude lines.

image of silver globe tucked away in the stacks of the Geography & Map Division
Unmarked silver globe sits in the stacks of the Geography & Map Division at the Library of Congress. Photo by author.

Last year, a friend of the Geography & Map Division, who is in possession of an identical globe, passed along some research he conducted on the manufacturing process of the globe itself. Documentation on the production of the globe is recorded in “Rock Island Arsenal, Ordnance Corps, Department of the Army:  A Historical Summary, 1 July through 21 December 1955,” a report issued by Rock Island Arsenal in Rock Island, Illinois.

Panoramic view of the Rock Island Barracks
“Rock Island, Ill.,” by C. Speidel, 1864. Geography & Map Division.

The Rock Island Arsenal was established on a small island in the Mississippi River between Davenport, Iowa and the city of Rock Island, Illinois in 1862. Between the end of 1863 and summer of 1865, the Rock Island Prison Barracks operated as a prison camp for Confederate soldiers captured during the Civil War. Post-Civil War, the site was turned into an arsenal and a manufacturing center for military supplies, such as weapons, ammunition, vehicles, and other equipment. The Sanborn Fire Insurance map below, dated 1950, shows the Rock Island Arsenal situated in the Mississippi River across from Moline, Illinois.

Sanborn map showing the city of Moline and Rock Island Arsenal
“Sanborn Fire Insurance Map from Moline, Rock Island County, Illinois,” Sanborn Fire Insurance Company, 1950. Geography & Map Division.

In 1955, it was the Rock Island Ordnance Corps who manufactured the globe. The report, “Rock Island Arsenal Ordnance Corps, Department of the Army: A Historical Summary, 1 July through 31 December 1955,” describes the manufacture of a 34-inch sphere for the United States Army Corps of Engineers. The intended use of the globe is described as “for earth study.” The manufacturing process itself is described as a “considerable achievement” for the Arsenal Operations Division.

 

Longitudinal lines are etched into a large diameter globe
“Photograph 9” from “Rock Island Arsenal Ordnance Corps, Department of the Army: A Historical Summary, 1 July through 31 December 1955.” Photo taken November 2, 1955.

The Army Corps of Engineers were thrilled with the final product, praising Rock Island Arsenal for “exceptional care in design and workmanship” of the globe. Part of that achievement was using specialized equipment to construct the sphere’s precise longitude and latitude lines: each groove is exactly .005 inch wide and .003 inch deep. The above image, taken from the report, shows the industrial machinery required to etch the latitude and longitude lines into the sphere.

Latitude and longitude lines etched into the surface of the globe.
A close-up of the etched longitude and latitude lines on the highly reflective surface of the globe. Photo by author.

The globe is very precisely scaled and described as being “1/15 millionth” the size of the physical earth. The globe itself is 5/16 inch thick and composed of castings of Almag 35, which is an aluminum magnesium alloy. The top of the globe is described as a “magnetic plug” which seals three separate sections together, each section connected by a rod running through the interior of the globe.

Large-diameter sphere with mount
“Photograph 7” from “Rock Island Arsenal Ordnance Corps, Department of the Army: A Historical Summary, 1 July through 31 December 1955.” Photo taken November 23, 1955.

After the manufacture of the first 34-inch globe, it is noted that the Rock Island Arsenal anticipated also producing a 50-inch and 100-inch globe. Intriguingly, the report also mentions the manufacture of a “support structure” created for the Argonne National Laboratory. Combined, it appears that there were two possible holding mechanisms for the globe: it could be hung from a hook, using the loop at the top, or could rest on its mount.

Nearly 70 years after its production, our globe still rests securely on its specialized mount. How many globes in total Rock Island Arsenal produced, and how exactly they were used, are questions in need of future research.

Further Reading and Sources Consulted:

  • U.S. Army Garrison Rock Island Arsenal: History
  • Rock Island Arsenal Ordnance Corps: A Historical Summary, 1 July Through 31 December 1955.” Rock Island Arsenal, Rock Island, Illinois.

Source: https://blogs.loc.gov/maps/2024/08/the-history-of-a-rock-arsenal-globe/

The History of a Rock Island Arsenal Globe