Can anyone tell me the age plus identify what model or type the above pictured Patterson lamp is please?

This lamp stands 9 inches high and has 4 metal pillars that protect the glass. This should place the lamp as a pre 1914 type after which date five or more pillars became mandatory. The lamp is stamped Patterson & Co / Newcastle on Tyne in between two of its pillars . It has a an old screw type lock which still retains its original screw. The lamp's fuel vessel is stamped "54" at a point just above the screw lock. Underneath the screw lock it is stamped an "L". Its bonnet is stamped "400" this being the lamp's identification number.  The lamp's has a single gauze which has a copper ring around its bottom plus has a wick priker that moves the wick up and down.