ght as the working of divine
vengeance to a remote descendant of the offender by forcing him to break
his tabus, the story is one of the most terrible in the whole range of
Irish literature.

FOOTNOTES:

[881] The religious interdictions mentioned by Caesar (vi. 13) may be
regarded as tabus, while the spoils of war placed in a consecrated place
(vi. 18), and certain animals among the Britons (v. 12), were clearly
under tabu.

[882] Joyce, _OCR_ 332 f.

[883] _Book of Rights_, ed. O'Donovan, 5.

[884] _Book of Rights_, 7.

[885] Ibid. 3 f.

[886] _LL_ 107; O'Grady, ii. 175.

[887] In Highland tales _geasa_ is translated "spells."

[888] _RC_ xxii. 27 f. The story of _Da Choca's Hostel_ has for its
subject the destruction of Cormac through breaking his _geasa_ (_RC_
xxi. 149 f.).

CHAPTER XVIII.

FESTIVALS.

The Celtic year was not at first regulated by the solstices and
equinoxes, but by some method connected with agriculture or with the
seasons. Later, the year was a lunar one, and there is some evidence of
attempts at synchronising solar and lunar time. But time was mainly
measured by the moon, while in all calculations night preceded day.[889]
Thus _oidhche Samhain_ was the night preceding Samhain (November 1st),
not the following night. The usage survives in our "sennight" and
"fortnight." In early times the year had two, possibly three divisions,
marking periods in pastoral or agricultural life, but it was afterwards
divided into four periods, while the year began with the winter
division, opening at Samhain. A twofold, subdivided into a fourfold
division is found in Irish texts,[890] and may be tabulated as
follows:--

1st quarter, _Geimredh_, beginning with the
_A_. Geimredh festival of _Samhain_, November 1st.
(winter half)
2nd quarter, _Earrach_, beginning February
1st (sometimes called _Oimelc_).

3rd quarter, _Samradh_, beginning with the
_B_. Samhradh festival of _Beltane_, May 1st (called also
(summer half) _Cet-soman_ or _Cet-samain_, 1st day of
_Samono-s_; cf. Welsh _Cyntefyn_).

4th quarter, _Foghamhar_, beginning with
the festival of _Lugnasadh_, August 1st
(sometimes called _Brontroghain_).

These divisions began with festivals, and clear traces of three of