Hump Fill Pens

 

During that hectic period when the lever was still patent protected, makers scrambled to design and manufacture alternative filling systems that would allow a pen to be called “sell-filling”, an essential designation if a pen were to be up-to-date in 1910. One approach was The Hump. (For the purposes of these thoughts, I am considering the hump to be different from the crescent - - which although similar in appearance, has no internal moving parts.) Paul Wirt offered pens like this based on his design patented in 1907 (#852,368). The pen has a metal bar attached to the end cap. A twist or two to open the cap, draws the bar away from the gold stopper seen under the hump. The hump is now free to be pressed onto the sac, allowing the pen to be filled. Closing the end cap moves the bar toward the section where it pushes against the stopper, causing it to seat under the hump. The pen is now secured from accidental discharge. While more complicated than the lever, it remains good enough to earn a “self filling” claim. In 1912, A. L. Watts developed a different and simpler approach to locking the hump (Patent #1,020,327), a design that was apparently licensed by the Chicago based Grieshaber Pen Co. This is how the design was illustrated in the patent application:   Not a very illuminating rendering without a listing of all the call-outs shown, it might be easier to understand by looking at the actual pen. The pen has a crisp imprint that includes the patent date, 3-12-12, which made it easy to track down the source of the design…     ... and like the Wirt, it has a threaded end cap. However, in this design, the cap is fitted with a long hollow tube that slides over the closed, domed end of the sac…  ... and the function is elegant in its simplicity. The open end of the tube is cut diagonally so that it has a leading edge. As the cap is screwed back into place after filling, that edge eventually pushes against the hump, securing it in place. While ingeniously uncomplicated, there are three potentially problematic elements in the design. The first, and least likely possible problem, would arise if the leading edge of the tube were to be chipped or broken. Should that happen, the tube would not reach the hump to secure it in place, but so long as the tube is not completely removed from the barrel, as it is shown in the photo, the likelihood of that damage, while possible, is remote. The second, and more likely problem to arise, would result from the tube rubbing against the sac which could cause premature wear, failure and a pocket full of ink. The third, and most likely problem would occur if the tube, when screwing it back in place, were to snag on a full sac of ink and twist it…an occurrence that begs the question, “Was talc in use on sacs in 1912?". While it is always easy, if not glib, to fault efforts that have not withstood the test of time, I can only admire the thought, energy and ingenuity these early pen makers brought to bringing the written word to a page reliably; with ease and efficiency. A volatile, eventful time, as makers attempted to get over the hump of a patent protected lever. Addendum: Paul Bloch has been in touch to let me know that on May 3, 1910 Benjamin Grieshaber was awarded patent #956,895 for his own design of a Hump Fill pen. Why BG chose to use Adams’ Mar. 12, 1912 patent date on the pen he manufactured is beyond me.

Text and images © 2015 Dan DeMaio

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