For many collectors, the ultimate experience is to dig at an insulator factory site, search an old threadless telegraph line, or poke through the shelves of a utility company but for me it is to roam endless stacks of material in some archive of information. While attending a conference related to my teaching, I had that experience when I was able to spend two-and-a-half days in the Patent and Trademark Office (PTO) in Washington, D.C. in May.

Banks of work stations in the Patent & Trademark Office. 
Rick Soller at one.

Since I was on a break, I could leave for the conference several days early. I wanted to look up foreign patents and the PTO had a great collection of these. My wife, Nedra, drove me to the train station which took me to downtown Chicago where I walked two blocks to catch the Elevated train to the airport where I boarded a plane to Baltimore and rented a car to drive to Arlington, Virginia, across the river from D.C. On the return trip, I regretted not taking a more direct route since I had to lug my suitcase loaded with photocopies for long distances as a result. It was like carrying two Chicago phone books around with me.

Even though I left at 8:30 in the morning and the flight was less than three hours long, it was 4:45 in the afternoon before I got to the PTO. I figured I only had 15 minutes to look around but I was excited and thought I might at least get a lay of the land. I was delighted to learn that even though the office containing foreign patents closed at 5 p.m., the first floor office housing U.S. patents was open until 8 p.m. With some help from the reference desk, I quickly found where the U.S. patents were located and went to work. 

The floor housing U.S. patents is designed to help patent examiners, attorneys, and inventors find relevant patents. As a result, patents are put into cubby holes according to classes and subclasses. Most insulators, for example, are found in class 174 (Electricity: Conductors and Insulators). Within this class, there are 212 subclasses including Lightning Protection (subclass 2), Lightning Protection-Rods (subclass 3), Insulators-Mid-line Spacers (subclass 146), and Insulators-With Terminal Elements-Pin Type (subclass 194). If a patent is relevant to multiple classes and subclasses, a copy is made and the patent can be found in each location. 

Cubby holes in the Patent & Trademark Office.

The amount of space this cross-referencing requires is immense. I estimate that the first floor is about the size of a football field. I counted 117 rows of shelves that spanned two buildings. Each row is divided into two sections by a path down the middle. Each section has 63 columns of cubby holes. Each column has 28 cubby holes. When you do the math, there are 412,776 slots that a patent could be filed in. To get at a particular cubby hole, there is a map that tells you what row the class is in. Above each column in that row is a card that tells you what patent subclass is filed in each of the 28 slots. Most subclasses take numerous slots. Physically, each row is a narrow 22 inches wide making it difficult to turn around or get at patents on the bottom.

The long rows of shelves on the left 
and cubby holes on the right in the 
Patent & Trademark Office.

I thankfully learned that I did not need to manually copy patents I found. Once I found a patent number, for 25 cents a page I could get a laser copy of the patent by using a work station near the entrance. My first order of business, then, was to pull all the patents on a subclass that interested me, write down all the patent numbers, and print them. After writing down over 1100 patent numbers, I knew I would have to be selective since the average patent was 3 pages long and I wasn't prepared to spend over $800 on making copies. That was like leaving an E.C.& M. behind so you could carry a California Electrical Works insulator out of the woods.

On day two, I was at the PTO when it opened and immediately went to the second floor to look at foreign patents. Here the work was much more labor-intensive. Indexes had to be used to find the patent numbers and patents had to be manually copied. I was also disappointed that only abbreviated patents were available for most countries. French patent journals only had a one-line description of the item and no picture. Some patent journals did not go back to the beginning as I expected or were in storage where it would cost $25 to have them brought to this location. Still, I did not run out of things to do and managed to get through 10 years of British abbreviated patents. 

I also explored the library on this floor and found some treasures. My favorite was an original copy of the 1912 Brookfield catalog. What shocked me was that the insulator pictured on the cover was dark green rather than being the same color as the cover as on the catalog reprint I own. The picture of the factory inside was also green. The library also had a 1930 Thomas catalog, a copy of The Locke Story, some obscure conference reports (e.g., Digest of Literature on Dielectrics) , a few issues of the NGK Review, and some books I would like to get like an English book titled, "The History of Electric Wiring." 

Half of my suitcase on the return trip was filled with photocopies. I'm looking forward to reading them, trying to contact inventors who may still be alive, matching the patent to the insulators in my basement, and putting some on my web page. At one point, I though I might just make a book out of them but I now realize there are just too many of them and more that I could get. I really only scratched the surface there and think it would be a great idea if, just like with the Smithsonian, some NIA members would coordinate some research there. On my way home, I took a bump from the airline in exchange for a free future flight so I would be willing to return for another round at the PTO.