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BOOK IV
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63
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Indian usage, called camphora. We
know this to be true because Averroes writes that amber is a species of
camphor; because Serapio writes that it forms abundantly when the earth
is shattered with earthquakes and then, commonly, both sulphur and
bitumen pour forth with great force; because certain springs of warm
water along the Aemilia Road smell of camphor; because merchants say
that they have seen a place in India that exudes camphor. Since the
native camphor from India is colorless and, in part, tenuous and finely
fibrous, it differs from the white naphtha of Babylonia. That which is
brought to us in the small cakes is artificial. It is prepared in the
following manner. Indian bitumen which effloresces from native camphor
is placed in earthenware vessels and heated over burning coals. The
more tenuous portions of the bitumen, having been changed to a white
color, are carried upward to the lid. It is then collected and given
the form we see. For this reason it happens that merchants sometimes
bring us pieces of bitumen along with the camphor from India. But this
association, in itself, is of little value. Actually if a cotton cloth
is moistened with water and placed in the lid of the vessel in which
oil is being extracted from amber, the cloth will have the odor of
camphor.2 Not without cause has Avicenna said that amber has
a strong camphor odor. It catches fire and burns with the same ease as
all other bitumens. Nevertheless the Moors and the younger Greek
writers who follow them have another theory regarding the origin of
camphor. They say it is the gum or the tears of a tree with such
wide-spreading branches that it is able to shade an area large enough
to accommodate a hundred men with ease. The wood of the tree is said to
be white, ferulaceous, light, and with the camphor contained in the
porous heart of the tree. Obviously a dream. The tree is said to grow
in mountains near the ocean. When they think camphor to be either
tears, resin or gum, the Moors do not consider why it is that the
Indians would have any cause to extract the more tenuous parts from it
over a fire. No matter from what kind of a tree a juice may come, if it
is very pleasing and useful, it is used in the form in which it occurs
naturally. For example, myrrh, bdellium, benzoin and other similar
tears are brought to us in the same form as that in which they are
exuded from the tree. Similarly, frankincense, storax, and other resins
and even the gums of ivy, juniper, peach, and other trees are not
altered. But, on the other hand, we often extract the more tenuous
portions of other mineral substances in this manner, for example, from
mercury and calamine. Therefore it is very probable, as certain
merchants relate, that camphor is made from a certain genus of bitumen
by distillation.3
8 Although camphor and amber have the same general composition, C10H16O,
they are only distantly related, chemically. There are many organic
compounds that have an odor similar to camphor. When heated amber
yields succinic acid, often called oil of amber and a bituminous
residue. Agricola refers here to this acid
*
Several closely related terpenes can be produced from bitumen but they
were probably not being produced in the time of Agricola. Today these
compounds are called camphors.
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