"-- For I Am -- Stumped"

Here's a trivia question which has bothered me for about a month, so I'm throwing it open to the masses.

As we all know, Steve Englehart often referred to very early Batman comics in his classic Detective run. One which I haven't been able to place is Dr. Phosphorus' note to the police from Detective #469:

Phosphorus burns when exposed to the air! The good citizens of Gotham City have earned my righteous wrath, and they will burn for it -- for I am -- Dr. Phosphorus

I don't think the note's content is really a reference, but the "-- for I am --" signature (with the dashes) really feels like one. I have skimmed all my reprint books (the first two Batman Archives, the first Dark Knight Archives, and the first Batman Chronicles), which cover Detective #s 27-75 and Batman #1-4, and come up empty.

Anybody out there know the answer?

Thanks!