In the early water storage pens, ink could not flow freely. When the writer presses the piston, the ink begins to flow. After writing for a while, he has to press it again, otherwise the ink will not flow out. Of course it's inconvenient to write like this.
1829, the British james bailey successfully developed the nib. After special treatment, it is smooth and elastic, and it is quite smooth to write, which is deeply loved by people. But this pen must be dipped in ink to write, which is very troublesome.
By 1884, an employee of an American insurance company named Waltman invented a capillary ink supply method, which solved the above problems well. The end of this pen can be disassembled and ink can be injected with a small dropper.
The earliest pen that can absorb ink by itself appeared at the beginning of the 20th century, using a piston to absorb ink. When using a bladder in a pen, insert an iron sheet into the gap to squeeze the bladder to absorb ink. At 1952, there appeared a snooker pen with a tube inserted in the ink to absorb water. The commonly used capillary pen was not invented until 1956. And some art pens.
It's hard to say who invented it first.