+

ledge of the period now under our notice, says',
"Much useful experience had been acquired in the
practice of arts and manufactures; but the science
of chemistry owes its origin and improvement to
the industry of the Saracens. They," he adds,
"first invented and named the alembic for the pur-
poses of distillation, analysed the substances of the
three kingdoms of nature, tried the distinction and
affinities of alcalis and acids, and converted the
poisonous minerals into soft and salutary medicines."
The formation and realisation of the notions of ana-
lysis and of affinity, were important steps in che-
mical science, which, as I shall hereafter endeavour
to show, it remained for the chemists of Europe to
make at a much later period. If the Arabians had
done this, they might with justice have been called
the authors of the science of chemistry; but no
doctrines can be adduced from their works which
give them any title to this eminent distinction.
Their claims are dissipated at once by the application
of the maxim above stated. What analysis of theirs
tended to establish any received principle of chemis-
try?
What true doctrine concerning the differences
and affinities of acids and alkalis did they teach? We
need not wonder if Gibbon, whose views of the boun-
daries of scientific chemistry were probably very wide
and indistinct, could include the arts of the Arabians
within its domain; but they cannot pass the frontier of
science if philosophically defined, and steadily guarded.
1 Decline and Fall, vol. x. p. 43.

VOL. I.

The judgment which we are thus led to form respecting the chemical knowledge of the middle ages, and of the Arabians in particular, may serve to measure the condition of science in other departments; for chemistry has justly been considered one of their strongest points. In botany, anatomy, zoology, optics, acoustics, we have still the same observation to make, that the steps in science which, in the order of progress, next followed what the Greeks had done, were left for the Europeans of the sixteenth and seventeenth centuries. The merits and advances of the Arabian philosophers in astronomy and pure mathematics, we have already described.

3. Experimental Philosophy of the Arabians.The estimate to which we have thus been led, of the scientific merits of the learned men of the middle ages, is much less exalted than that which has been formed by many writers; and, among the rest, by some of our own time. But I am persuaded that any attempt to answer the questions just asked, will expose the untenable nature of the higher claims which have been advanced in favour of the Arabians. We can deliver no just decision, except we will consent to use the terms of science in a strict and precise sense': and if we do this, we shall

2 If I might take the liberty of criticising an author who has given a very interesting view of the period in question (Mahometanism Unveiled, by the Rev. Charles Forster, 1829), I would remark, that in his work this caution is perhaps too little ob

find little, either in the particular discoveries or general methods of the Arabians, which is important in the history of the inductive sciences.

The credit due to the Arabians for improvements in the general methods of philosophizing, is a more difficult question; and cannot be discussed at length by us, till we examine the history of such methods in the abstract, which, in the present work, it is not our intention to do. But we may observe, that we cannot agree with those who rank their merits high in this respect. We have already seen, that their minds were completely devoured by the worst habits of the stationary period,-mysticism and commentation. They followed their Greek leaders, for the most part, with abject servility, and with only that kind of acuteness and independent speculation which the commentator's vocation implies. And in their choice of the standard subjects of their studies, they fixed upon those works, the Physics of Aristotle, which have never promoted the progress of science,

served. Thus, he says, in speaking of Alhazen (vol. ii. p. 270), "the theory of the telescope may be found in the work of this astronomer;" and of another, "the uses of magnifying glasses and telescopes, and the principle of their construction, are explained in the great work of (Roger) Bacon, with a truth and clearness which have commanded universal admiration." Such phrases would be much too strong, even if used respecting the optical doctrines of Kepler, which were yet incomparably more true and clear than those of Bacon. To employ such language, in such cases, is to deprive such terms as theory and principles of all meaning.

except so far as they incited men to refute them; an effect which they never produced on the Arabians. That the Arabian astronomers made some advances beyond the Greeks, we have already stated: the two great instances are, the discovery of the motion of the sun's apogee by Albategnius, and the discovery (recently brought to light) of the existence of the moon's second inequality, by Aboul Wefa. But we cannot but observe in how different a manner they treated these discoveries, from that with which Hipparchus or Ptolemy would have done. The variation of the moon, in particular, instead of being incorporated into the system by means of an epicycle, as Ptolemy had done with the evection, was allowed, almost immediately, so far as we can judge, to fall into neglect and oblivion: so little were the learned Arabians prepared to take their lessons from observation as well as books. That in many subjects they made experiments, may easily be allowed: there never was a period of the earth's history, and least of all a period of commerce and manufactures, luxury and art, medicine and engineering, in which were not going on innumerable processes, which may be termed experiments; and, in addition to these, the Arabians adopted the pursuit of alchemy, and the love of exotic plants and animals. But they seem to have been so far from being, as has been maintained', a people whose "experimental

intellect" fitted them to form sciences which the "abstract intellect" of the Greeks failed in producing, that the case appears rather to be, that several of the sciences which the Greeks had founded, were never even comprehended by the Arabians. I do not know any evidence that these pupils ever attained to understand the real principles of mechanics, hydrostatics, and harmonics, which their masters had established. At any rate, when these sciences again became progressive, Europe had to start where Europe had stopped. There is no Arabian name which any one has thought of interposing between Archimedes the ancient, and Stevinus and Galileo the moderns.

4. Roger Bacon.-There is one writer of the middle ages, on whom much stress has been laid, and who was certainly a most remarkable person. Roger Bacon's works are not only so far beyond his age in the knowledge which they contain, but so different from the temper of the times, in his assertion of the supremacy of experiment, and in his contemplation of the future progress of knowledge, that it is difficult to conceive how such a character could then exist. That he received much of his knowledge from Arabic writers, there can be no doubt; for they were in his time the repositories of all traditionary knowledge. But that he derived from them his disposition to shake off the authority of Aristotle, to maintain the importance of experiment, and to look upon knowledge as in its infancy,