New greenbacks: how to make a buck - literally - design of new paper money; includes article about detering counterfeiting - Cover Story

Science News, Jan 27, 1996 by Richard Lipkin, Damaris Christensen

This led Congress in 1861 to authorize a new paper currency. Printed with inexpensive green ink on one side, these greenbacks could not be copied with the cameras of the time. Congress standardized U.S. bills in 1863, incorporating deterrents such as the seal of the Treasury Department, fine-line intaglio printing, and a distinctive paper with embedded red and blue fibers.

In 1865, the treasury established the Secret Service to wage war against forgers. One of the most notorious was William E. Brockway. This New York-based "king of counterfeiting" passed hundreds of thousands of bogus bills between 1850 and 1890. Aided by the recently introduced deterrents, which forced professional forgers to use specialized skills and equipment, the Secret Service suppressed the largest counterfeiting rings, including Brockway's.

U.S. currency has undergone several changes since then. In 1869, the treasury introduced a watermarked paper with bands of dark jute in the substrate. In 1879, it changed the paper to a linen stock containing parallel red and blue silk threads and eliminated the watermark. In 1929, the size of the dollar bill was reduced about 25 percent to save on paper costs, and small, dispersed red and blue fibers replaced the silk threads. Standardizing each denomination's portrait prevented counterfeiters from raising a note's value simply by altering the numbers.

In 1990, two new features appeared: a metallic security thread and a line of microprinting around the portrait. The threat posed today by casual counterfeiters using color copiers has prompted the treasury to suggest several additional changes (see main story).

"There is no single, perfect deterrent," says Thomas A. Ferguson, assistant director of research and development at the Bureau of Engraving and Printing. In fact, "an awful lot of people don't know about the [deterrent] features already in the bill-most of us have never gotten a counterfeit.

"And that's our goal, to keep it that way."