What makes this period so interesting? Two things:
1. Frequent postage rate increases. 2. The proliferation of commemorative se-tenant issues and souvenir sheets, many of which were never intended to be used for postage.
It is important to understand the factors that make a cover scarce and desirable. These factors are the same, no matter what time period we are talking about. There are many, but the main three factors are:
RateRoute and DestinationFranking The rate of the cover is the amount of fees that were required to pay for postage and any other services that were purchased in connection with the delivery, such as special delivery, ac…