I found this image on Wikipedia. Is this a MH gumball ? The NEMA tag appears to be red, however the wattage is invisible in this picture.

http://fr.wikipedia.org/wiki/Fichier:Toronto_Streetcar_Trolley_Wire.jpg

Could have originally been mercury, but retrofitted to a HPS lamp, either a drop in one or with a parallel starter added.

Those gumballs are 100 watt PSMH, they are made by Cooper lighting but replaced the more classic incandescent and mercury gumballs back in the mid 90's. You can see a comparison picture here. This style of gumball still gets installed as well!

Yeah and I've seen 70w and 150w versions used too depending on the size of the street.

Thanks, this situation now makes sense.

These are Cooper URB gumballs.

I think the NEMA tags on the URB gumballs here are factory but I've seen some goofs too including once where they applied the NEMA tag upside down. The URB gumballs are no longer made and Toronto has been using bare aluminum King Luminaire teardrops for replacements and new installs.

I think the NEMA tags on the URB gumballs here are factory but I've seen some goofs too including once where they applied the NEMA tag upside down. The URB gumballs are no longer made and Toronto has been using bare aluminum King Luminaire teardrops for replacements and new installs.

Yes I've seen those too.