The New Orleans crescent. [volume] (New Orleans, La.) 1866-1869, 1869-04-04

of the new system OF educauon over the oio,
of the modern method over the classical
method. 1t may also be regarded as q
triumph of the rational phenomenal philoso-
ply over the metaphysical superstitions
which have heretofore dominated the realm
of education; and it may likewise be consid-
cred as conspicuous illustration of that
amazing revolution in physical science
which has marked the history of the
present generation. For it is fact that
the physical science Of to-day, approx
mately coordinated into q body of congruous
physical doctrine, differs scarcely less from
the segregate and apparently hopelessly d.
yergent physical sciences of thirty years ago,
than the Copernican system of astronomy,
illustrated by the Newtonian law of universal
gravitation, differs from the Ptolemaic sys-
tenn, arbitrarily constructed upon fanciful
foundation of imaginary cycles and epicycles.
This revolution, grand as it is, and remarka-
Bile as have already been its effects upon the
widest generalizations of which the human
mind is capable, has scarcely yet been felt
hardly even has it been recognized in our
schools and colleges. The unhappy youth of
the era are doomed to grope through an anti
quated series of text books filed with false
doctrine and exploded hypothesis, and when
they leave school they are astonished to find
that they really know as little of true physical
science as medieval sailor would know of the
steam engine. They discover that, whilst
they have acquired many facts, they have i'm
bibed number of false theories which, at
best were only provisional in their nature;
and that they have absolutely no conception
at all of that magnificent generalization which
has united the physical sciences into one con-
gruous and harmonious system. Students
who have been taught that heat and electricity
and magnetism are certain imponderable fluids,
and to whom the undulatory theory of light
has been revealed only as a curious specula-
ton, find it difficult to understand that these
phenomena are only varying manifestations of
force, or motion, resulting from molecular ac-
ton, and can scarcely comprehend the funda-
mental doctrine Of modern physics, that the
sum of all existent forces is uniform and in
variable, and that it can no more be increased
or diminished than the sum of existent mat
ter can be increased or diminished This
truth, which is now automatic, and which is
considered an priori cognition of the high
est order, is known as the doctrine of the
Conservation of Force" according to Spen-
Ger, persistence of Force" In the hands of
Mayer, Grove, Helmholtz, Farraday, Tyndall
and others, it has led to complete reyolu-
ton in physics, and constitutes the founda-
ftion of that grand law of evolution, discov-
cred by Mr.. Herbert Spencer, and to the re-
gime of which that wonderful man has SUBJ
jected the whole body Of physical and PSYCHE
cal science. f.s
But the doctrine of the "persistence OF
force" is almost unknown in the schools, and
in order to grasp it firmly in the mind, those
who have gone through the standard course
of physics, are compelled to unlearn much
which they learned under the name ofknowl-
edge. 1t is not to be supposed, however. that
the influence of the new philosophy will not
at last effect the same revolution in our sys-
tenn of primary instruction that has already
been accomplished in our real knowledge.
The time is not far distant when the text
books will conform to the discoveries OF
Tyndall and Helmholtz and their co-laborers,
and when our institutions of learning will ac-
cept the teachings of the great apostles of
science. II it is true that "Science moves but
slowly, slowly, creeping on from point to
point" it is true that old systems of instruc-
ton move still more slowly. Nevertheless,
we have before US the proof that they do
move. We have it in an unpretending volume
just issued from the press of Woolworth,
Ainsworth & Co., Boston, called "Natural
Philosophy for High Schools and Academies, -
by w. J. Role and J. A. Gillet, teachers in
the High School, Cambridge, Massachusetts,.
This book constitutes one of the Cambridge
course ofphysics. We cannot give better
idea of its plan than by quoting a passage
from the preface: "The authors felt, from
experience, that the elementary text books on
| physics, now in use, are, as class, deficient
in two important particulars. First, they are
sadly behind the times; and secondly, they
fail to give any systematic development Of
leading principles. A great revolution has
taken place during the last twenty-five years
in the departments of chemistry, electricity
and heat. In chemistry this revolution has
been SO complete that the present theories of
the science are currently known as modern
! chemistry The hypothesis of electric fluids
has been swept away, and heat has been
shown to be mode of molecular motion. 1t
is but recently that Helmholtz has given the
correct explanation of the formation of the
vowel sounds, of resultant Is and of dssonance;
and that Tyndall and others have investigated
the subject of sounding and sensitive flames.
In optics, too, the cause of long and short
sightedness, and the way in which the eye ad-
justs itself for near and distant objects, have
been correctly understood only within a few
years. In astronomy, also, the analysis OF
solar and stellar light by means of the spectre
scope has led to discoveries of the highest in
terest, while recent investigation has thrown
much light upon the nature of the photosphere
and spots of the sun"
We do not say that this book is all that