Dating parker 51 Freerandomcamsex
In 1947 the arrow clip was simplified, eliminating the earlier Blue Diamond mark (for the simplified clip, see the image at the top of the page), and at the end of 1948 the filling system was changed from a multi-stroke pump (taken over from the Vacumatic; cross-section above) to a squeeze-bulb ("Aerometric") with a transparent "Pli-Glass" sac (see photo below).
The 51 forced competitors yet again to respond to Parker innovation, releasing their own "hooded" pens that were generally not as revolutionary inside as the 51.
Compared to many fountain pens, both its contemporaries and more recent models, the “51”, with its monochrome plastics and its tiny nib that lies hooded within a shell, might be considered a Plain Jane.
But the “51” was not designed to be an eyecatching display piece.
The 51's key design features (the hooded point, the sleek monochrome barrel, and fashionable metal slip-cap) have rightfully earned it a place in the annals of styling and design, but what's interesting to me is that all of these features were dictated by technical considerations more than by esthetics.
In the early 1930s, Parker set about the task of making a pen that would write with a dry line, like a pencil.