1their clarity is as crystal to mud in comparison with
those of his predecessors—
and of most of his successors for over two hundred years. As an indication of
his grasp of some of the wider aspects of geological phenomena we reproduce,
in Appendix A, a passage from De Ortu et Causís, which we believe to be the
first adequate declaration of the part played by erosion in mountain sculpture.
But of all of Agricola's theoretical views those are of the greatest interest which
relate to the origin of ore deposits, for in these matters he had the greatest
opportunities of observation and the most experience. We have on page 108
reproduced and discussed his theory at considerable length, but we may repeat
here, that in his propositions as to the circulation of ground waters, that ore
channels are a subsequent creation to the contained rocks, and that they
were filled by deposition from circulating solutions, he enunciated the founda
tions of our modern theory, and in so doing took a step in advance greater than
that of any single subsequent authority. In his contention that ore channels
were created by erosion of subterranean waters he was wrong, except for
special cases, and it was not until two centuries later that a further step in
advance was taken by the recognition by Van Oppel of the part played by
fissuring in these phenomena. Nor was it until about the same time that the
filling of ore channels in the main by deposition from solutions was generally
accepted. While Werner, two hundred and fifty years after Agricola, is
generally revered as the inspirer of the modern theory by those whose reading
has taken them no farther back, we have no hesitation in asserting that of the
propositions of each author, Agricola's were very much more nearly in
accord with modern views. Moreover, the main result of the new ideas
brought forward by Werner was to stop the march of progress for half a
century, instead of speeding it forward as did those of Agricola.
and of most of his successors for over two hundred years. As an indication of
his grasp of some of the wider aspects of geological phenomena we reproduce,
in Appendix A, a passage from De Ortu et Causís, which we believe to be the
first adequate declaration of the part played by erosion in mountain sculpture.
But of all of Agricola's theoretical views those are of the greatest interest which
relate to the origin of ore deposits, for in these matters he had the greatest
opportunities of observation and the most experience. We have on page 108
reproduced and discussed his theory at considerable length, but we may repeat
here, that in his propositions as to the circulation of ground waters, that ore
channels are a subsequent creation to the contained rocks, and that they
were filled by deposition from circulating solutions, he enunciated the founda
tions of our modern theory, and in so doing took a step in advance greater than
that of any single subsequent authority. In his contention that ore channels
were created by erosion of subterranean waters he was wrong, except for
special cases, and it was not until two centuries later that a further step in
advance was taken by the recognition by Van Oppel of the part played by
fissuring in these phenomena. Nor was it until about the same time that the
filling of ore channels in the main by deposition from solutions was generally
accepted. While Werner, two hundred and fifty years after Agricola, is
generally revered as the inspirer of the modern theory by those whose reading
has taken them no farther back, we have no hesitation in asserting that of the
propositions of each author, Agricola's were very much more nearly in
accord with modern views. Moreover, the main result of the new ideas
brought forward by Werner was to stop the march of progress for half a
century, instead of speeding it forward as did those of Agricola.
In mineralogy Agricola made the first attempt at systematic treatment
of the subject. His system could not be otherwise than wrongly based,
as he could scarcely see forward two or three centuries to the atomic theory
and our vast fund of chemical knowledge. However, based as it is upon
such properties as solubility and homogeneity, and upon external character
istics such as colour, hardness, &c., it makes a most creditable advance
upon Theophrastus, Dioscorides, and Albertus Magnus—his only predecessors.
He is the first to assert that bismuth and antimony are true primary metals;
and to some sixty actual mineral species described previous to his time he
added some twenty more, and laments that there are scores unnamed.
of the subject. His system could not be otherwise than wrongly based,
as he could scarcely see forward two or three centuries to the atomic theory
and our vast fund of chemical knowledge. However, based as it is upon
such properties as solubility and homogeneity, and upon external character
istics such as colour, hardness, &c., it makes a most creditable advance
upon Theophrastus, Dioscorides, and Albertus Magnus—his only predecessors.
He is the first to assert that bismuth and antimony are true primary metals;
and to some sixty actual mineral species described previous to his time he
added some twenty more, and laments that there are scores unnamed.
As to Agricola's contribution to the sciences of mining and
metal
lurgy, De Re Metallíca speaks for itself. While he describes, for the first
time, scores of methods and processes, no one would contend that they
were discoveries or inventions of his own. They represent the accumulation
of generations of experience and knowledge; but by him they were, for the
first time, to receive detailed and intelligent exposition. Until Schlüter's
work nearly two centuries later, it was not excelled. There is no measure by
which we may gauge the value of such a work to the men who followed in
this profession during centuries, nor the benefits enjoyed by humanity
through them.
lurgy, De Re Metallíca speaks for itself. While he describes, for the first
time, scores of methods and processes, no one would contend that they
were discoveries or inventions of his own. They represent the accumulation
of generations of experience and knowledge; but by him they were, for the
first time, to receive detailed and intelligent exposition. Until Schlüter's
work nearly two centuries later, it was not excelled. There is no measure by
which we may gauge the value of such a work to the men who followed in
this profession during centuries, nor the benefits enjoyed by humanity
through them.