This is essentially just a smaller version of the Number Seven, which had been on the market for about a year. Like the Number Seven, this model was an excursion outside the numbering system Waterman had been using since at least the turn of the century on its hard rubber pens; the number gave a vague sense of size, while the only other detail Waterman thought the user might care about was indicated by a colour.
That colour was not quite what one would expect, though, as it was not the colour of the pen’s body. That was consistent, with all early models being red ripple hard rubber which gave way about half-way through the run to black celluloid (other colours may have appeared right at the end of the run, but I have not documentation for it). The colour was a means of indicating immediately what sort of point the pen had, which reduced the amount of searching for both buyers and shop staff. The following chart gives the colours and what they meant, drawn from Waterman’s advertising over several years:
The first six on this chart were available right from the start in the Number Seven, but apparently Waterman was concerned about there only being six styles of Seven; I’m not clear on whether the seventh style was added before the Number Five was brought into play. You may also notice that there are more than seven colours on this chart, but any given source of advertising only refers to seven of them, with Purple occasionally stepping aside for one of the newer variants.
In the rubber versions of this pen, the colour was indicated by a band around the top of the cap. When the change to celluloid was made, the indicator became an inset disc in the tail of the pen. On either side of this line, the model number was impressed into the tail, as it had been in the earlier pens, allowing one to tell a Seven from a Five without having check the length.
You can, by the way, refer to these as “No. 5”, since Waterman used both in their own advertising.
Production Run: 1928 – c.1934.
Cost When New: $5.00, throughout the run, regardless of material (for modern values, try this calculator).
Size: 12.8 cm long capped, 16.3 cm posted, 11.9 cm uncapped (rubber model).
Point: 14K gold.
Body: Rubber until sometime after 1930 (a catalogue dated 1930 still shows rubber for this model), then celluloid.
Filler: Lever , capacity approx. 1.4 ml
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