Perforations on the 1967-1973 Centennial Issue
Today, I turn to another aspect of this issue that has received little attention from philatelists: the perforations on this issue. Most collectors with a passing familiarity know that five basic perforations exist, but they tend to pay little attention to them, in large part because the stamps with different perforations are often very easily distinguished on the basis of other characteristics. However, as we shall see, there are other aspects to the perforating that should be understood by anyone opting to specialize in this issue, for it is the possession of this knowledge that opens up the possibility of important discoveries being made later. There are three attributes of perforations that are of interest here: Whether the perforations are line perforations or comb perforations. What the measurement of the perforations are (i.e. the gauge), and whether there is any significant and consistent variation to be found. Whether the perforations extend all the way through ...