The sun. [volume] (New York [N.Y.]) 1833-1916, 1878-05-26

that we in America must strive to write. Let us
content ourselves with aiming 10 put new wine
in the old bottles for 1t is scarcely worth while
to deny on the score OF a dozen native idioms
which may be dcfcnsiblc on abstract grounds.
that the court Of last resort in matters Of lingu-
istic usage Is TO be found not on this but on tho
eastern side Of the Atlantic NJ. w. IL.
Norman Lockyer on Spectrum Analysis.
No volume OF the international scientific
series is likely to ind more readers. both on nc
count Of the wel-known competence Of the au-
thor and OF tine intrinsic interest OF the subject
than Studies ia Spectrum analysts 10y J. NORMAN
LocKYER tAppletonsl. When we consider how
tardily and imperiectly the fruits OF research
in older fields have been translated from the
technical and shorthand idom Of professional
Investigators into the speech OF common life,
and made generally Ineligible by lucid exposl-
ton. we must regard with the most lively salts
faction this earnest and successful attempt to
make familiar the newest. and. for that reason.
the most reconcile Of the sciences. The reader
Will need no special training 10 follow the per-
spicuous outline Of this treatise, and he will
bring away from II clear notions Of the visas
already opened beyond the old horizon Of our
knowledge. and OF the far wider conquests
promised. by tho analysis of the solar spectrum.
Few persons who know anything about the
subject matter OF this volume will be likely to
dispute Mr. Lockyer's assertion that either the
present or at all events. the next generation,
will be esteemed by future times rs no less
favored than that which saw tho invention OF
the telescope or the discovery OF Newton BY
the one achievement our knowledge Of the uni
verse was almost infinitely extended. while TO
tho other We owe the law that like energies act
everywhere in the same way but so. In our day
does the spectroscope show US that like matter
II acting in like manner through all the regions
OF space. and under all conditions Of existence
So that II matter and energy be not identical.
we are now for tho first time enabled. with the
help Of this new science. to understand one Of
the two foundation stones OF the Cosmos in
which we dwell In tho effort to interpret this
youngest OF the sciences which permits US 10
study matter whcresoever situate from an en-
tirely novel point OF view. Mr. Lockyer strives to
aid our conceptions by mental images derived
from more familiar departments Of research.
or from ordinary phenomena Thus he Is care
fu at the outset. and this instance will illustrate
his method. to fix upon the mind the distinction
between the undulatory theory Of light. which
forms 81 course. the fundamental ground Of tho
new science. and the corpuscular theory which.
n is well known. was held by Newton, md
which continually crops up in common speech.
This he docs cncctually by likenug the visible
ray in the one case 10 n message sent by the
electric wire. ami under the other. now general
ly discarded. hypothesis 10 parcel sent by rail.
In other words. it is not thing. but
state Of things. which travels and tho author
suggests n second useful Image. while remind
ing Us that in shaking a rope We send the state
OF things We call a wave along il. without the
rope itself travelling rs whole In tho case 81
fltac iii Ia. -
dlton OF compression and rarcfnction OF the
air, Just rs the rope wave WAS pleNus %. alter
nate compression and loosening OF It's strands.
Very much in the same way tho luminiferous
disturbance or light-wavc produced by n light
sender or radiator II transmitted along IA some
thing which physirsts call ether" infinitely
less gross in stru ,ture than air. and which is
conceived 10 pervade all nature and pcrmcato
all bodies. without. Of course. a. well Hs within,
the narrow circuit OF our atmosphere. We are
not, however. 10 picture TO ourselves the
motions OF the particles of ether IN Il light
wave ne similar in all respects TO
the unduatory movements which take place
in other media. They are widely different. for
instance from the circular orbits Of tho MOLE
culcs Of water-wave. which take place in
vertical plane in the direction OF motion and
equally SO from the forward and backward sway
OF a particle Of air in the direction OF motion OF
n sound disturbance. In the first place. the
motion Of the ether atoms II transverse to the
path OF the disturbance that is the vibrations
occur in planes perpendicular TO the direction
Of the ray. Thus. II row OF balls in a straight
limo be taken TO represent particles OF ether at
rest, and il we suppose these balls TO start sue
cessively. and vbrate uniformly up and down.
We shall get a wave system established along
the whole line and Wa shall at once Apprehend
the ideas OF wave length and Of amplitude
After devotlng a good deal Of space to an elu-
cidation Of light upon the data Of tho unduato-
ry theory, Mr.. Lockyer goes on to remind us
that the solar ray is not necessarily limited to
transmission through the ether in free space
that II a glass OF port wine, for example. is held
NJ TO the sun the emergent ray looks red, and
that, accordingly, IL we would study light pho.
nomena completely. we must not only take into
account the circumstances connected with tho
sender and the receiver, but also those peculiar
TO the media, which may interfere with the nor
nal passage OF light through ether; which in
other words, absorb it; for, although we do not
know that ether itself absorbs light yet We may
safely ar IN TINT everything else does
But absorption is not the only result which
follows from tho ENHANCEMENT OF the ethor
waves among the molecules OF foreign matter.
If the disturbance, for instance, is travelling in
such direction that it passes into n substance
denser than air, such AS water or glass. and
otherwise than perpendcularly TO tho surface.
change ensues in the direction of propnga-
ton of disturbance, the wave changes front, so
to speak and the greater the difference in
density between tho two kinds of mattur tho
greater will be- this divergence. But the change
OF front is accompanied by something which
is directly pertinent to the object of
this treatise, and which can be studied
best when We make tho disturbance
enter and leave the surfaces Of the dcnser body
at the Same angle. This can be accomplished
by using glass and shaping it into the form Of
a prism, which, held athwart the ether disturb
ance, not only warps tho ray out Of it's course,
but If it be beam Of white light splits it up into
Its constituents, each represented by a distinct
color; or, II the incident ray be OF any special