The sun. [volume] (New York [N.Y.]) 1833-1916, 1900-05-29
fists. The most striking piece Of the

sraph This consists OF a long tube OF cotton
duck with one end IN an underground cabin Az
the other end Ia u five-inCh lens which gives an
image OF tho sun four inches In diam"t"r NV"
pssatiyes we're taken with this INSTRUMENT dur
Ing totali,y. II IA designed Ia bring out the
inner corona and tho ChrOmOsphere proinl-
nencss. ,
Near this "a n shed containing two equatorial
telescopes, a small equatorial mounting Tor
observing he polarization OF III" corona. ana a
large polar axis carrying a number OF separate
Instruments Tho cQuntorials were used Tor
skstohlpg the corona by hand. The equatorial
mounting carrie. two cameras provided WIN
double image prisms. ono giving two Images 81
the corona itself, the other Two Images oil inc
coronal spectrum. Besides These there Is u
small telescope containing polarlzlng apparatus
IN the tube. All thee Instruments belong 10
the Johns Hopkins University party, lhey
were used 10 Determine the amount ana dlrec-
ton OF the polar light in the corona.
ON the polar axis there ara two Dallmsyer
lenses mounted side by side with these a num-
Der Of photographs were taken TO determine
VIII ,her tho distribution OF the substance CIV
ing the bright green line II Ihe corona spectrum
IA the same as TINT Of the other particles he
sides these there Is "a small telescope for eve
work and a camera containing n lens with vide
aperture aud extremely short focal length,
This was exposed Throughout tOiallty. the Oh
ject being TO record ~ much as possible ~ tho
longest s,realncrs OF the corona, the brighter
central part being much over ext, sed This
lens belongs 10 Yale I University and was orer-
s,rd by Mr. Kent of New York. formerly "A Yale
student ard now AZ Johns Hopkins
To the left Of the shed stand the spectroscopes
OF llc Johns Hopkins party. This Is the first
time that asystemali' attempt has been mad"
10 use grating- in eclipse observations One
Grating is ruled on n Nat surface. tho other on
on "A concayn spherical surface Five photo
graphs were taken with each OF these instrn-
menis, giving the spectrum Of tho corona AZ
different periods during lOtaltv
On the other sid, Of the shed Prof Wood OF
Wisconsin had set up ht- apparatus, con-iS,ing
Of two stroboSCopes to determine the period OF
the shadow bands. "A telescope and "A polarl-
scope.
Tn" weather to-day has been almost cloud
less The astronomers, were at IN" observatory
by $40 making the last preparations FOR the
eclipse. An hour and n half later tho crowd
began TO gather. including tho families OF The
Observers and many negroes, The North Caro-
lima darkey has little TO ~av, hu, his fac' shows
anything but amu'ement when an cell 50 comes
OF. Fortunately for the success OF tho work,
the spectators kept well outside ot the ropes
The first contact. that j. the moment when
the edge Of III" moon first appeared 10 touch the
edge Of IN" suns disc, was noted by 'onf OBJ
server. TIA" m"nn Of their four obServat ons
was 1870 correction ~ I a-lp Srrond' isto
be slbtractcd from MIS- Tor III" clock error.
u living Tho Qgtlnl Tine As I 80 N I-ll. Almost pA-
acily the calculated instant
As the suns d Sc diminished to a crescent "A
phenomenon was Observed which - simple
enough To those familiar with optical effects,
but appear very s,rnnG" TO the nnini'a'"d.
7 his Is the Tact that Whenever light from the
eclipsed sun passes through n small opening
ard falls on a screen beyond, the rat'h 81 Iigot
appears in III" shape OF a crescent and not
round "a ia usually III" cose This i
especially striking where the iight Sits
through the leaves Of "A Tree ON the
grass beneath appear n great number OF
crescents. reproducing exactly The image "
the sun. The explanation IL nipple. Light
proceeding from any object through a snrli
opening throws on n screen an mag. of the
same shape as the object i,Se (. independent OF
the shape of the opening Foo this reason, "A
beam of sunlight passing through u hole ina
shutter casts on the wall of a room u round
patch Of light which - al image of The sun In
the case OF an eclipse. shortly before or after
totally, the sun j. crescent shaped, ConSe-
ouently the light patches appear a. crescents.
This ls The principle which i made use of IN the
so-called ''pinholr Photograph
Al : 30 so much Of the sun was covered that
the dimInution in tn i~ntrn-it, OF tn" light was
anita striking A. tl. grtSIpnf tniuupt -tll