In 1894 and following successive improvements to his 1889 patent, George S. Parker had the Curve Tubular Overfeed properly perfected. In 1896 this device would be improved and adapted as underfeed in the #2X Parker models according with Patent No. 606,231, which we will soon know as Lucky Curve. This innovative element established a continuous capillary connection between the nib and the inner walls of the barrel avoiding some of the particular problems that, in its time, had the use of fountain pens; difficulty starting the ink flow when starting to write; poor, excessive, or uneven ink flow; ink dripping from the pen when the reservoir was not full or nearly empty, and ink overflowing through the section when the pen was reversed after use.
“This peculiar little piece of crooked and curiously shaped piece of rubber, which the cut so faithfully represents, is one of the features which has helped to make the reputation of the Parker Pen. The perfection with which it feeds ink to the pen, and absolutely prevents the ink from getting over the edge of the nozzle or into the cap, when carried in the pocket.”
At the end of 1898 Parker acquired the 3 upper floors of the McKey Building Block at 17-19 South Main Street in the heart of Janesville´s downtown. On the side of this building had a large-scale ad, where we could read: The PARKER PEN COMPANY, Home of the JOINTLESS FOUNTAIN PEN.
In his constant search for improvement, Parker tackled the common problem of ink-stained fingers, eliminating the joint between the barrel and the section, whether it was this union by thread or by friction of both elements. A particularly delicate area since it is from there that we take the fountain pen while writing.
“The Pen with no joint to leak; no threads to break. The pen with the Lucky Curve. The success of the pen age. You cannot soil your fingers with a Parker Jointless.”
«Sour Look, soiled fingers and spotted clothes identify the man who did not use a Geo. S. Parker fountain pen.”
His invention of a «Jointless» fountain pen -without joints- added extra security to the use of these writing instruments. In late 1897 Parker was already producing the Jointless Lucky Curve.
The Parker Jointless were easily distinguishable at the base of the barrel as they have added a zero as first figure over the equivalent models with joint old style.
In 1900 Geo. S. Parker also found a solution for the caps, then brittle and expandable hard rubber: it could separate from the barrel inside the pocket and were very fragile in its mouth, where the closing pressure was applied, being prone to cracking. Parker patented a cap whose interior, approximately half its length, widened its walls and it was there, in a thicker area and without a profile prone to cracks, that the closing pressure was supported.
The inside of the cap is made in such a way that all the strain that ordinarily exists at the open end of the cap is transforred from the end, to the inner body of the cap, of greater thickness and consistency.
With a Parker Jointless Lucky Curve 023 was signed the 1898 Treaty of Paris, which ended the Spanish-American War.