The No 15, along with the short-lived No 16, appear to have been the economy lines in the range of pens that Conway Stewart issued in the early nineteen-fifties. The patterned ones were made from casein, and beautiful though they are, they are less interesting to me than the single-colour pens, which Jonathan Donahaye believed are made of celluloid acetate. I’m not sure how he came to that conclusion. Perhaps he had a better sense of smell than me, or maybe he accidentally set one on fire. Casein doesn’t burn well but a celluloid pen in flames is memorable.

I had a No 15 in the colour that Jonathan described as “deep brown” arrive the other day. As luck would have it, among my stock was a No 475 which he had described as “uniform chocolate brown”. Comparing the two, they seemed identical to me. I should have photographed the two together, but the 475 found a buyer and is at present winging its way to him, courtesy of Royal Mail. So it goes.

In any case, I would swear that colours, and hence in all probability the materials, were the same. The 15 and 475 also share “uniform forest green”. Is this enough to say that there is a relationship between these pre- and post-war pens? Both are at the economy end, neither have cap rings and both come in innovative colours and patterns that don’t occur elsewhere in the production of their respective periods. Is the CS 15 in some sense the successor to the CS 475?

The brown almost comes across as black in photos, so here it is with a black Swan.

The Conway Stewart 15 comes in two sizes, the larger at 12.9 cm being the same size as the commoner CS 75, and the smaller one half a centimeter less. The uniform coloured ones especially are an exercise in minimalism, being about as plain as a pen gets. The nib is smaller than that of the CS 75 and it has a different profile, being more wraparound in the style of the CS388 nib. Minimalist or not, it’s a handsome little pen, except for the clunky plastic stud that retains the clip. That does detract from the pen’s appearance, and it suggests that the pen was made to fit a price.

I like the CS 15s, though, and I’m glad to have finally found a deep brown one. I need a forest green and a deep blue to make the set. To be exact, there’s also a grey, but like all nineteen-fifties greys, whether by Conway Stewart, Parker, Swan or Wyvern, they tend to take on a yellow discoloration and are hence less attractive, so I might forget about that one.