In Waterman’s case, “early” is a very broad span indeed. For the moment, I’m limiting myself to those made in roughly the first four decades of the 20th century, which have model numbers rather than names. This leaves a seventeen-year stretch before the turn of the century, which I don’t have any direct contact with and fear to speak of.
The period from 1900 to about 1927 saw Waterman doing much the same as most of the other notable pen-makers of the day, offering pens with descriptive code numbers rather than the more evocative names one is now used to. This numbering system has two phases, with a change-over in 1917. Prior to that date, the codes were relatively simple and strangely uninformative; an initial digit to indicate a variation in body followed by a digit to describe the point size (1 to 0, in increasing size, the 0 being a #10 point), and in some versions a set of letters to indicate variation from the standard eyedropper-filling model and possible extra furniture. This system worked, but was not extremely flexible, and could lead to confusion; the suffix PSF could mean two entirely different types of filler mechanism, depending on just when a pen was made. This problem arose because the system was instigated before there were any filler mechanisms to worry about.
1917 saw an expanded code system, which was more capable of describing a broad range of pens in an unambiguous manner. Because it’s so comprehensive, it seems a little impenetrable, but if one had access to the explanation chart in the catalogue, it wasn’t so bad… in theory. The main point of agreement between the two systems was that the right-most digit indicated the point size (which has some bearing on the barrel size, as the body remains roughly proportional to the point). The next digit to the left became an indication of the filler type and the general shape, and left again showed a body decoration; this last item could be a two-digit number, giving a possible total model number of four digits, or five if one counts the “½” which indicates a slender version.
There does not appear to have been any adaptation of the system for the introduction of various coloured rubbers, though, which means that even before it was dropped it was not entirely capable of describing a pen completely. With the appearance of celluloid, the system began to break down. In some models, there was a vestigial deference to it as late as 1936, but other models bore only a single number and some a name. As a general rule of thumb, if a Waterman isn’t made of rubber, it falls outside this system, but if it is rubber, however late (and the current notion of an end to rubber Watermans is 1934), it does.
For the most part, there’s not a lot of guesswork about what a pen’s number is; they were imprinted on the tail of the pen, and frequently highlighted with red wax.
Production Run: 1900 – 1934 (broadly; specific models may vary as noted).
Cost When New: Noted on individual examples (for modern values, try this calculator). Clips were an extra-cost item up until about 1925, adding between 50¢ and $3.00 to the cost of the pen, depending on material, pen size, and just when one is looking.
Point: 14k gold.
Filler: Varies, see individual examples.
No. 12 Production run: 1900 – c. 1925 (the last year I can find it in a catalogue, although it may run later). Cost $2.50 in 1902 catalogue, $2.75 in 1925 catalogue. Eyedropper, capacity approx. 2.6 ml. Dimensions: capped 13.4 cm, posted 17.0 cm, uncapped 12.2 cm.
No. 52 Production run: 1917 – c. 1934 (prior to 1917, it would have been a No. 12PSF). Cost $2.50 in 1919 catalogue, $2.75 in 1933. Lever filler, capacity approx. 1.6 ml. Dimensions: Capped 13.5 cm, posted 17.0cm, uncapped 13.1 cm.
No. 52 1/2 V w.r. Production run: 1917 – c. 1934. Cost $3.00 in 1925 catalogue, slightly higher due to gold filled furniture. Lever filler, capacity approx. 0.6 ml. Dimensions (ring not included): capped 10.8 cm, posted 13.8 cm, uncapped 10.2 cm.
No. 01852 Production run: 1917 – c. 1934. Cost $4.00 in 1919 catalogue, still $4.00 in 1933 (because it was moving down-market). Lever filler, capacity approx. 1.6 ml. Dimensions: Capped 13.5 cm, posted 17.0cm, uncapped 13.1 cm.
No. 01852½, w.r. Production run: 1917 – c. 1934. Cost $3.50 in 1919 catalogue. Lever filler, capacity approx. 0.6 ml. Dimensions (ring not included): capped 10.8 cm, posted 13.8 cm, uncapped 10.2 cm.
No. 55 Production run: 1917 – c. 1934. Cost $5.00 in 1919 catalogue, $5.25 in 1925. Lever filler, capacity not noted when I had it in hand. Dimensions: 14.0 cm long capped, 17.6 cm posted.
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