[78-L] Dating Italian Acoustic Columbias.

[Spats]

Hi!

I've recently been transferring some of my Italian acoustic Columbia operatics.
These include some very underestimated singers.
However, I gather that much of the Columbia recording information of 
pre-electric days has gone astray or just been destroyed through 
warfare or whatever.

I wondered if any among you have any information whatsoever which 
would help me 'date' these records by their matrix numbers (or even 
through catalogue numbers: mostly on the 'D' series). I'm mainly 
interested in the period 1910-1925.

Thanks,

Earl Okin.