, 1879-03-29

astronomer In the lnnd. Various arc the thco-
rics Tint have been advanced to account for the
bomc observers consider 1t a ring o! mnttcr
teyplrtnE round the earth; ot1Iera Eo0k ,pnn
It ns d collection of minute particles
afmeseortc or cotnesic matter travelling around
the sun In very eccentric orbits. More recent
md mnre searching examination gives a far
grandcr explanation, of its origin, making tho
xodfsca1 1ight continuation Of the cnfona, n.tl
thus indicating 1enticular-shaped atmosphere
extending out near the plane Of Tic elliptic be-
yund the orbit Of tho earth. 0nr most Thought
fuf scicntsts do not acccpt bs view, but su9.
Ing. It Is Tint thu whole spaco bctwecn The
earth uu1 sui Is oiled With thlmensn clouds OF
nletcoroids, anl that the sunlight reflected on
these cosnical atoms Of floating star-dust Is The
caurc OF thr soft celestial glow Tint now lingcrf
crcnlnE after evening iii our Western aky.
ON TIE INERTIA OF THE RET1NA.
IT. truc of all The senscs that M interval has
to clapse between the application Of M sppro-
prfatc stimulus ansl tile development of the
corresponding scnsatton. Il certain degree Of
inertia has to be overcome. by means Of .
special apparatus for graduating a. will tic Ia
tensity of tho incident raya, Chnrpentter has
Investigated ttis phenomenon In relation 10 the
eye. II tic intensity Of the light be gradually
augmented from the zero-point, the sensation Is
developed when certain minimum Intensity ia
reached; but II the Intensity OF the stimulus be
now As gradually diminished, We ind that the
eye Will continue to perceive It till II mas fallen
TO oue.tbird OF one-fourth OF the orjginsi mini
mum. In producing the Initial sensation. >
certain amount Of light has, 50 TO speak, been
wasted In putting the machinery In nottose
Further, II the ere has been carefully shielded
from the light for some minutes before per-
forming the cxpcr!ncnt, It will bo capabtc Of
perceiTInE lieht which Is fifty Or ercn 1O0 times
lNsntnous sensation. THIS cnofEnoua difference
Ii equally manifested whether murochromatLc
Or wnlte lixht to emplo,ed Nov, II ~e apply
Or, ''' We find tlat for '''is:e' ths ct'romstic
as for the luminous stimulus = cer-
tain minimum Is needed to provoke the
sensation, which still continues to DO ex-
progressively diminished. 30 fur, the two sen.
sattons-ulat OF light and TINT of culor-otey
the sasne Inv. But II We proceed TO compare
We sens!t!seness q the eye IN tY,l activity with
of absolute rest, VIC no longer find any such Ill
creasv in it, susceptibility to the chEomattc
stinaulus ~ was observed In tho case 0f light.
THIS result il altogether opposed TO the current
opinion thu. tar sensation excited by white
tight 70 really resultant OF tile atmultancous
development Of 6eveEal detcrminate cnloF-sen-'
saions; i shows. on th contrary. that the sctl-
satiou of light 10 altogether independent OF tlat
OF color, and really simpler kind VI reaction
on tho part Of the visual apparatus.
ON NATIONALITY IN FRANCE AND
GERMANY.
In recent interesting paper on the subject,
II, Derst1lou comments On the fact that all the
effort VI ulr French agricultural reputation the
turifty bou1geosie, is applied 10 forming ind
eatrfv rHrttRy fh., nj ~ hnn