o Masses on the same
day--one for the current feria and one for the feast (_festa_). Other
authors say that the word is derived from the ancient practice of
chanting twice or in repetition the complete responses and versicles.
And, above all, the recitation of the full antiphons before and after
each psalm, at Matins, Lauds and Vespers, was called "duplication," and
this name, it is said, was given to the office (double, duplex) in which
the practice of duplication took place.

It is often asked why are there different grades of feasts. Three
reasons are given by writers on liturgy. First, to mark the diversity of
merit in God's saints, their sanctity and their different degrees of
service to His Church. Second, to mark their different degrees of glory
in Heaven. "One is as the sun; another, the glory of the moon; and
another the glory of the stars. For star differs from star" (1 _Cor_.).
Third, for some special national or local reasons--e.g., patron of
a country.

The rules laid down in the general rubrics in the new Breviary, for
doubles and semi-doubles, are left unchanged almost by the regulations
laid down by the Commission and by the _Variationes_. Their numbers were
reduced, so that there now stand in the new Breviary only seventy-five
doubles, sixty-three semi-doubles, and thirty-six movable feasts.

A reason for the new arrangement of double feasts in the Pian Breviary
is the general one, that the Pope wished above all things the weekly
recitation of the Psalter, and to bring about this weekly recitation and
the restoration of the Sunday Office a mere rearrangement of the Psalms
was quite insufficient, and a rearrangement of the gradation of feasts
of concurrence and of occurrence was necessary.

TITLE II.--THE OFFICE OF A SEMI-DOUBLE.

_Etymology, nature and synonyms_. The word semi-double (_semi-duplex_)
is derived from the Latin; and some writers hold that the word indicates
feasts which are of lower rank and solemnity than double feasts. Others
hold that it means simply, feasts holding a place between double feasts
and simple feasts. Most writers on liturgy hold that on some days a
double office--one of the feast and one of the feria--was held, and that
in order to shorten this double recitation there was said a composite
office, partly of the saint's office and partly of the feria; and they
say that from this practice arose the term semi-double, or half-double.

Synonyms for the term "semi-dup