, another quarter with
the complete maturation, and another quarter terminates the complete
absorption of a material now rendered inoffensive to the constitution.

* * * * *

SECT. XXXVII.

OF DIGESTION, SECRETION, NUTRITION.

I. _Crystals increase by the greater attraction of their sides.
Accretion by chemical precipitations, by welding, by pressure, by
agglutination._ II. _Hunger, digestion, why it cannot be imitated out
of the body. Lacteals absorb by animal selection or appetency._ III.
_The glands and pores absorb nutritious particles by animal selection.
Organic particles of Buffon. Nutrition applied at the time of
elongation of fibres. Like inflammation._ IV. _It seems easier to have
preserved animals than to reproduce them. Old age and death from
inirritability. Three causes of this. Original fibres of the organs of
sense and muscles unchanged._ V. _Art of producing long life._

I. The larger crystals of saline bodies may be conceived to arise from the
combination of smaller crystals of the same form, owing to the greater
attractions of their sides than of their angles. Thus if four cubes were
floating in a fluid, whose friction or resistance is nothing, it is certain
the sides of these cubes would attract each other stronger than their
angles; and hence that these four smaller cubes would so arrange themselves
as to produce one larger one.

There are other means of chemical accretion, such as the depositions of
dissolved calcareous or siliceous particles, as are seen in the formation
of the stalactites of limestone in Derbyshire, or of calcedone in Cornwall.
Other means of adhesion are produced by heat and pressure, as in the
welding of iron-bars; and other means by simple pressure, as in forcing two
pieces of caoutchou, or elastic gum, to adhere; and lastly, by the
agglutination of a third substance penetrating the pores of the other two,
as in the agglutination of wood by means of animal gluten. Though the
ultimate particles of animal bodies are held together during life, as well
as after death, by their specific attraction of cohesion, like all other
matter; yet it does not appear, that their original organization was
produced by chemical laws, and their production and increase must therefore
only be looked for from the laws of animation.

II. When the pain of hunger requires relief, certain parts of the material
world, which surro