Toulouse shows the IG Co in a diamond mark as dating from 1900 to 1916,
however if the bottle has an Owens suction scar than it would date after
1910. This is the year that the Illinois Glass Company secured a lease to
use the Owens machine. The dates for different companies acquiring leases
to use the Owens machine are outlined in a paper presented at the SHA last
January titled "Dates for Suction Scarred Bottoms: Chronological Changes in
Owens Machine-made Bottles." Let me know if you would like a copy.
George L. Miller
URS Corporation