Conway Stewart produced the 'Scribe 330' model between 1931 and around 1940.  There were three slightly different imprints and this pen has the earliest of them, dating the pen to 1931/1932.

The pen is constructed in Black Chased Hard Rubber (BCHR), There is some brown patina, I have made no attempt to change it as it is really part of the aging process.  The brown patina is accelerated by exposure to light, so a pen that has been kept in the dark, a box, for example may still retain the black colour.  The surface is good and has a nice finish, the imprint is just legible. 

There is a second imprint which reads 'Education Supply, Oxford'.  I think it highly unlikely that the pens were supplied to schools, fountain pens were relatively expensive items after all.  Most 'state' schools were using dip pens up until the 1960s.  Perhaps the imprint refers to Oxford University or a company that supplied Eton and the like!  

A very distinctive and practical feature of the Scribe is the arrangement of threads on the end of the barrel to facilitate posting of the cap.  In this configuration the pen is a most impressive 16.5 cm. in length.

The barrel imprint reads:

The balance of the pen is also important, ideally the centre of mass should be close to the 'jaw' between index finger and thumb.  It is no accident that, if the cap is posted by screwing on to the end of the barrel, as it is designed to do,  the centre of mass, and the lever, are exactly in this position. 

At ninety odd years old the Scribe is not recommended as an every day pen to be carried around in a pocket or bag, but it would make an excellent 'signature pen 'to be used for letters, cards etc. or just for the joy of using a genuine vintage, soon to be antique item.