The Security Building is at the left side of this picture, on the Southeast corner of Main & Harvey. This 1912 image looks South on Harvey.

Also visible, right foreground, are the Majestic Building, followed by Mellon's and Goodholm Building.

This image is from The Vanished Spendor (Vol II), written and assembled by Jim Edwards, Mitchell Oliphant (Abalache Book Shop Publishing Co, Okc, 1983).