ho
have studied this matter, the following may be considered as a fair and
accurate summing up:--

In the first ages of the Church the Apostles and Martyrs only were
commemorated in public prayers and, above all, in the Mass, perhaps, by
a special prayer. Then, in time, followed the reading of a panegyric in
their honour, and later still hymns and histories of martyrdom were
added to the public recitation of the Office. Still later, there were
added the feasts of the saints with an office resembling our simple
office. Matins were entirely ferial, but had either a biography of the
saint or a long extract from the Fathers added. The other hours were as
in a Sunday office, save that these feasts had no Vesper matter.

In still later times, the Church added to the list of names on her saint
roll, the names of saints who were honoured neither as Apostles nor as
Martyrs. For these, special Masses, offices and feasts were established.
St. Martin of Tours was the first confessor so honoured in the Western
Church. For the more important feasts, an office of nine lessons was
established and this came to be known as a semi-double office, and later
such feasts were called doubles. Hence, before the thirteenth century,
we find celebrations of simple feasts, of semi-doubles and of doubles.
And Durandus, who wrote in the thirteenth century, tells us of the
existence of doubles major and doubles minor. The Breviary of St. Pius
V., published in 1568, gives three classes of doubles: doubles of the
first class, doubles of the second class, and doubles per annum. But, in
the revision by Clement VIII. the doubles per annum were again divided
into doubles major and doubles minor. In the new Pian Breviary (1913)
doubles are divided into Primary Doubles of the First Class, Secondary
Doubles of the First Class; Primary Doubles of the Second Class,
Secondary Doubles of the Second Class, Primary Doubles Major, Secondary
Doubles Major. The list of feasts under each of these six headings may
be seen in the Breviary.

Do double offices differ specifically from each other? No, the form is
the same in all double offices. What then is the difference between
doubles of different classes? The difference is chiefly in the
preference which is given to them in cases of concurrence or occurrence
of feasts of greater or of lesser rite.

The word "double" (_duplex_) is derived, some authors hold, from the
ancient custom of reciting two offices or saying tw