when cut with a steel knife dissolves some of the iron, and becomes of a dark colour where cut."
Professor
Stewart states that one part of Copper is to be found in four million
parts of water which has been left to stand for three hours in a Copper
vessel (having the capacity of a litre). For a typhoid fever patient
this very small percentage of Copper in solution has proved sufficient
to kill off the " typhoid microbic guests, without doing any harm to
the host." " Colloidal " Copper is the technical term applied to such
Copper in solution.
"
There's fevers of the mind," said Mrs. Gamp, shaking her head
mysteriously, " as well as body." " You may take your slime drafts till
you flies into the air with efferwescence ; but you won't cure that."
In
making cooking utensils of Copper, great care should be taken that acid
liquors, or even water intended for drinking, or to be mixed with food,
is not suffered to stand too long in any such a vessel; otherwise so
much of the metal will become dissolved thereby, as to give
disagreeable, and even poisonous qualities to the same. Yet, it is
remarkable that while acid liquors are kept boiling, they do not seem
to dissolve any of the metal. Thence it happens that confectioners, by
skilful management, prepare the most acid syrups in Copper vessels
without their receiving any unpleasant taste, or injurious quality
from the metal. But all vessels formed of this metal, which are
employed in cooking, ought to have their inner surface covered with a
coating of tin.
No
evidence whatever is adducible to show that Copper thus possibly
ingested in small quantities for long periods has caused any
detrimental effect on the health of an individual. Certain experiments
have been made
