The pages of Electrical Engineering, formerly the Southern Electrician, supply this month's ads.                    
                                                                                                                                       
                                                                                                                                         

July, 1913 illustrates suspension disks.

September, 1913 shows the Thomas #3008 which is M-3105.

October, 1911 show Thomas #1101 which is a U-267A.

Thomas insulator #2012 is depicted in this old ad. It is a U-927
glazeweld known to Thomas and rare for Imperial Porcelain.

This ad shows Thomas #1097. This is a U-593 and is 
unknown. Maybe someone out there has it 
sitting on their shelf and doesn't realize it.