Copyright © Françoise Herrmann
If quills required the writer to dip for ink, then the fountain or reservoir pen inventions promised a portable and continuous source of ink. However, before delivering on this promise many details were patented ranging from optimizing the ink flow and protection of the nib, to leak-proofing and methods of storing or adding ink within the pen.
In US209959, titled Improvement in fountain pens and granted on Nov. 18 1878, Alonzo T. Cross, primarily addresses the issue of ink flow, and incidentally the adjustability of the invention to various pens, as well as a certain degree of leak-proofing.
The invention discloses an air-tube with a small hole on its side and a friction joint enabling to adjust the amounts of air admitted into the ink chamber to regulate the flow of ink to the nib using gravity. The reservoir also cooperates with a delivery tube which may be further adjusted (extended or retracted) according to the size (and height of the nib). Finally, the air-tube is also equipped, at its lower end, with a small plug and pin enabling to wick any accidentally incoming drops of ink, using capillary action, when the air pressure system is set in motion from the top of the pen using the vent cap and the pen is prepared for use.
Again, for ease of comprehension and translation, and in the manner of the Alonzo T. Cross handwritten patents (e.g.; CA10682, CA17448) I have keyed the components of the invention and layered the key onto the patent figure drawing, both of which are appended below.