The collection includes over 1300 drawings from the Marconi Wireless Telegraph Company of America mostly produced from 1917 to 1919. Geographically, the vast majority seem to have been produced at MWTCA facilities in New York and New Jersey. However, the projects and equipment were meant for locations not only within the United States, but outside it as well, including Cuba, Argentina, Brazil, and the Philippines.

The Marconi drawings range in subject from circuit diagrams, wiring layouts, and switchboard schematics to architectural plans for aerial towers and carrying case designs. Especially noteworthy are the contract work designs where the buyer is identified. Over a hundred drawings are related to U.S. Navy projects, and over fifty are related to Army projects. There is an early airplane radio with a propeller generator designed to attach to the wing of the plane, a mule-pack radio set for the Army Signal Corps complete with leather saddle schematics, a blimp radio installation guide, and various equipment for boats of both marine and flying varieties. General Electric, Crocker-Wheeler Company, Lowenstein Radio Company, the International Telegraph Construction Company, and Electrose Manufacturing Company all appear in the notes on various documents. More than any other corporation, there are mentions of the United Fruit Company, famous both as propagator of ‘Banana Republics’ and as surprising pioneer in electronic wireless communications across their global empire. Historical curiosities include a diagram of the radio tower for Boston’s Filenes building, a 1912 Beaux Arts colossus designed by Daniel Burnham, and 1913 designs for mast caps at the South Wellfleet station in Massachusetts. That station had relayed the first transatlantic wireless message in 1903.

The drawings contain a wealth of information. The drawings also often contain annotations in pencil - emendations, revisions, notes, or simply the words ‘VOID’ or ‘OBSOLETE’ scrawled across them. Many contain a “Bill of Material” with amounts, and sometimes prices, per unit. They often include references to other drawings: lists of sub assemblies by drawing number, other views of the same item, wiring diagrams, cases, etc. Insofar as practical, those have been included in the ‘Notes’ section of each item’s entry. Sometimes the drawings specify materials, finishes, and even paint or enamel colors. Occasionally, man-hours are noted, especially when multiple people were involved. A 30 hour total time-mark seems standard for many of the drawings that have these notations – this could be a bias in noting time worked only for the most complex drawings, though.

The drawings from the David Sarnoff Library do not represent the full collection of drawings produced by the Marconi Wireless Telegraphy Company of America, nor even all the MWTCA drawings George Clark amassed throughout the 1920s, 1930s, and 1940s. Nearly 3,800 more drawings bearing catalog numbers from Clark’s Radioana collection (many duplicates of those in the Sarnoff Library) were found in the attic of a building originally part of the Marconi (and then RCA) New Brunswick campus in 1999 – the same plant where those incorporated into the Sarnoff Library were also found. They now reside at InfoAge Science History Learning Center and Museum of Wall, NJ. Judging by catalog numbers, George Clark’s total collection of Marconi drawings was well into the thousands; just filling in the gaps between catalog numbers held by Hagley and InfoAge indicates around 4,600 remain unaccounted for. Since certain catalog numbers repeat with letters appended, for example T 2144567-A, T2144567-B, it is impossible to know with exactitude how many may be missing, even assuming that every series is represented. Furthermore, it is safe to assume that Clark did not near his goal of collecting all the Marconi drawings. Applying the same process to the original MWTCA filing number, indicates around 14,200 are missing, even including those from InfoAge. Nonetheless, there are several stretches where dozens of Marconi consecutive numbers are preserved in order, between gaps of hundreds.