(seq. 45)

36

Materia Alimentaria

Light, Milk

food, I believe contrary to the opinion of Chaptall, Black
and others, that Calcareous earth is an original earth.
Light. Must be mentioned as one of the nutriments of
man, for nothing can exist long without it, all vegitables
become pale if deprived of this holy gift of Heaven, with
verry few exceptions. Milk. This is not a
homogenious substance but separates into cream, curd, and whey,
these separate after some time if exposed to the air. The
quantity and quality of the milk is verry much altered by
the food and constitution of the animal. It has been
remarked that red cows afford the most cream, and further
that flaxen haired women have less nutritious milk. The
part first seperated is the cream from this by a process
churned butter is obtained. Dr Cullen was of the opinion that
during the process there was no decomposition or increase of
heat, whereas Dr Young of Edinburgh always found the
increase of temperature to be about four degrees. The
rancidity of Butter I believe to arise from some other part than
the oily, I am led to believe thus, first because butter milk
mixed with it increases rancidity, secondly because it