[78-L] Lead-in groove mystery

[Gary Herzenstiel]

Hi, everyone.

I just picked up a Columbia Whiteman "potato head", numbered 2297-D with matricies 150788-3 and 150789-3, both recorded on 10 September 1930.  The label looks like this one:

http://78rpmrecord.com/labelshow.cfm?whichLabel=1143

Oddly, it has a lead-in groove.  It appears to be little wider than the normal audio groove, spirals in at a normal rate and starts from the edge of the record.  This seems very early for a lead-in groove.  Has anyone done a survey of lead-in and run-out grooves?  I was always told that they were developed for the jukebox industry but this certainly casts doubt.

Thanks.    Gary H
78rpmrecord.com
(more label scans than anyone should have - adds your scans!)