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186
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DE NATURA FOSSILIUM
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gold
with a hundred pounds of silver, merely a foolish practice that results
in a loss of money. A similar practice is to mix a pound of silver with
a hundred pounds of tin or copper. There are four alloys belonging to
this genus. One contains tin alloyed with copper. Pliny describes this
alloy. Ollaria is the latest name to be given it, the name
being derived from a vase. Three or four pounds of tin are added to one
hundred pounds of copper. A second alloy that does not differ greatly
from this is called bombardaria, a name taken from a new although foreign word since this is a new thing. The name comes from the large ordnance (bombarda) made
from it. Amazonae, basilisci, lusciniae, quartanea, dragons, serpents,
and falconets, both large and small, belong to this class of ordnance.
To make this alloy one pound of tin is added to twenty pounds of copper.27
A third alloy is made by adding a half pound of bismuth to sixteen
pounds of tin. This alloy rings and is usually hammered into platters,
plates and dishes. The English commonly add more bismuth and make
articles from it that closely resemble silver. The fourth alloy is made
by adding one part of tin or bismuth to two parts of lead. In olden
days this was used to join pipes and was called stannum tertiarium. There
is another alloy containing equal amounts of two metals, usually tin
and lead. In the time of Pliny they called this alloy stannum argentarium. Today
it is sometimes used in making goblets, dishes, platters, circular
vessels and similar objects. In general, these are the five ways in
which they alloy two simple metals.
There
are three alloys containing three metals, one new and two old. Pliny
writes, concerning the old alloys, that one was copper, gold and silver
but writes that it had become obsolete because of the casting of more
valuable copper. He describes the other in these words, "Until now it
has been called temperatura and has the form of very delicate
copper because a tenth portion of lead and a twentieth portion of tin
are added." This alloy can be colored with ease and is then called graecanica. The
new alloy is made by mixing ten pounds of tin, five pounds of lead and
two pounds of bismuth. Some add copper to the lead and bismuth in
varying quantities. Tinsmiths hammer this alloy into different objects.
I have found no mention of more than three simple metals being mixed
together nor one or more mixed metals being alloyed with another mixed
metal. However, a simple metal may be alloyed with a mixed metal, for
example, tin with stannum tertiarium. Pliny writes, "the alloy made from equal parts of tertiarium and tin is looked upon with disfavor."
Enough
about simple metals and their alloys. In the following book I shall
discuss the coloring of these metals, the crude ores, and the
artificial metals.
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