of fat are a sooty smoke and those of oily substances a greasy
steam. Oil does not boil away or thicken by evaporation because it
does not give off vapour but fumes. Water on the other hand does not
give off fumes, but vapour. Sweet wine does give off fumes, for it
contains fat and behaves like oil. It does not solidify under the
influence of cold and it is apt to burn. Really it is not wine at
all in spite of its name: for it does not taste like wine and
consequently does not inebriate as ordinary wine does. It contains but
little fumigable stuff and consequently is inflammable.
All bodies are combustible that dissolve into ashes, and all
bodies do this that solidify under the influence either of heat or
of both heat and cold; for we find that all these bodies are
mastered by fire. Of stones the precious stone called carbuncle is
least amenable to fire.
Of combustible bodies some are inflammable and some are not, and
some of the former are reduced to coals. Those are called
'inflammable' which produce flame and those which do not are called
'non-inflammable'. Those fumigable bodies that are not liquid are
inflammable, but pitch, oil, wax are inflammable in conjunction with
other bodies rather than by themselves. Most inflammable are those
bodies that give off smoke. Of bodies of this kind those that
contain more earth than smoke are apt to be reduced to coals. Some
bodies that can be melted are not inflammable, e.g. copper; and some
bodies that cannot be melted are inflammable, e.g. wood; and some
bodies can be melted and are also inflammable, e.g. frankincense.
The reason is that wood has its moisture all together and this is
continuous throughout and so it burns up: whereas copper has it in
each part but not continuous, and insufficient in quantity to give
rise to flame. In frankincense it is disposed in both of these ways.
Fumigable bodies are inflammable when earth predominates in them and
they are consequently such as to be unable to melt. These are
inflammable because they are dry like fire. When this dry comes to