We must here call attention to a change which took place about 1871 in the _character_ of the perforation made by the A machine. Up to that time the paper was very seldom even slightly pierced by the pins, or any of it removed—_i.e._, the perforation is what is called _blind_. A writer in the _Stamp Collector’s Magazine_ of December, 1866, speaking of St. Vincent stamps, thus describes it: “… the stamps … are perforated (if that term be quite accurate) by an instrument fixed in the machine, which leaves a series of indentations … which does not remove a particle of paper except in a very occasional spot, hardly one in a thousand. On severing the stamps by tearing, a rough indented edge is left…” This is quite correct, and we cannot better the description of the work of the A machine given by this old-time philatelist of nearly thirty years since, who collected and studied stamps in a day when perforation-gauges were not. It is only after 1871 that we generally (but not always) find the pins piercing through the sheet and leaving _small_ holes, the paper being thrust aside and turned back by the passage of the pins through it, but little or any of it being removed. We wish to call particular attention to this point; that is, that the holes are _small_, and that the portion of paper displaced is not clean-cut or punched out. If this be not attended to, these particular examples of the later work of the A machine may be confused with the clean-cut perforations of 1862, which we have yet to consider. It is to the vagaries of the B machine that we are principally indebted for the extraordinary number of perforations, simple and compound, that have been ascribed to the stamps of St. Vincent, as well as to those of the few other Colonies for which this machine was used. These Colonies are Antigua, Bahamas, Barbados, and Turks Islands. We know of no other instances in which the B machine was used, and in all these it was employed to a very limited extent as compared with its use in St. Vincent. Possibly this limitation was owing to the very unsatisfactory nature of its performance, and to the difficulty of separating the stamps without tearing them.