Heiser catalogues are accurately dated by adding 7 to the catalogue number. Catalogue 23 was issued in 1930. Turnerriver and I worked this out separately and Packing Iron generallyy agrees. The formula struggles a bit beginning with No. 50 and extends to 51 and 52, which appears to be a 58 (100 years since founding in 1858). Then the issuance of the Heiser-Keyston-lichtenberger versions the compay appears to have taken Keyston's own founding year as the basis for the formula.

None of which addresses how one would pay so much for one. I only value the info in them so am happy with copies :-).

Now, if you want some real fun, try dating Myres catalogues. Another mate of mine and I have successfully done this with references inside to the macroenvironment, which can be dated. So far it appears there is only a single Myres catalogue issued during the 1920s, while Heiser issued a catalogue every single year from 1908 onwards.

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Red Nichols The Holstorian