The shade has 4 reinforcement wires running from the central bronze crown down to the lower aperture of the shade.

There will be another reinforcement wire soldered arround te entire cicumference of the shade in a distance of 1-2 inches to the

lower aperture of the lamp.
 

This picture shows the shade from inside.  One of the 4 reinforcing wires you can see here, which are (following the seams) going down

to the lower end of the shade. Please do not mind the glass is looking very dirty, this is the bees wax which melts and comes out of the seams

while soldeing due to the heat of the soldering iron

The irregular lower border of the lamp is protected by a half round copper wire, which is adapted and soldered to the glass here.