s during the vernal
and summer months, the greater of the two diurnal tides in our latitude is
that, when the moon is above the horizon; and when the sun is in the
southern signs, or during the autumnal and winter months, the greater tide
is that, which arises when the moon is below the horizon: and as the sun
approaches somewhat nearer the earth in winter than in summer, the greatest
equinoctial tides are observed to be a little before the vernal equinox,
and a little after the autumnal one.

Do not the cold periods of lunar diseases commence a few hours before the
southing of the moon during the vernal and summer months, and before the
northing of the moon during the autumnal and winter months? Do not palsies
and apoplexies, which occur about the equinoxes, happen a few days before
the vernal equinoctial lunation, and after the autumnal one? Are not the
periods of those diurnal diseases more obstinate, that commence many hours
before the southing or northing of the moon, than of those which commence
at those times? Are not those palsies and apoplexies more dangerous which
commence many days before the syzygies of the moon, than those which happen
at those times? See Sect. XXXVI. on the periods of diseases.

VII. Another very frequent cause of the cold fit of fever is the quiescence
of some of those large congeries of glands, which compose the liver,
spleen, or pancreas; one or more of which are frequently so enlarged in the
autumnal intermittents as to be perceptible to the touch externally, and
are called by the vulgar ague-cakes. As these glands are stimulated into
action by the specific pungency of the fluids, which they absorb, the
general cause of their quiescence seems to be the too great insipidity of
the fluids of the body, co-operating perhaps at the same time with other
general causes of quiescence.

Hence, in marshy countries at cold seasons, which have succeeded hot ones,
and amongst those, who have lived on innutritious and unstimulating diet,
these agues are most frequent. The enlargement of these quiescent viscera,
and the swelling of the praecordia in many other fevers, is, most probably,
owing to the same cause; which may consist in a general deficiency of the
production of sensorial power, as well as in the diminished stimulation of
the fluids; and when the quiescence of so great a number of glands, as
constitute one of those large viscera, commences, all the other irritative
motions are affected by