The Pacific commercial advertiser. [volume] (Honolulu, Hawaiian Islands) 1885-1921, 1897-11-16
FAIR DAY WANTED
Prof. Buckhalter to Photo.
graph the Eclipse.
En- Route per the Battle-Ground for
india-A Master of Coronal
Photography

Prof. Chas. Burckhalter, F. r. A. S.,
was passenger by the Belgic for In
dia to observe the eclipse. He inquired
for his friend Captain Kidwell and
spent a couple of hours with his old
acquaintance Frank Davey, the photo
grapher. This scientist is director of
the Chabot Observatory of Oakland
and professor of astronomy and geolo-
gy in the Oakland high school. Profess
sor Burckhalter presented the follow
ing account of his expedition as being
| authentic:
The programme of work for the
Chabot astronomer is not nearly so Ella
borate as that mapped out by Profess
sor Campbell of the Lick Observatory,
but it has one advantage over all other
eclipse expeditions in that Burckhalt-
er's Photographic method is entirely
original, and has never been previously
utilized in eclipse work. The "Pierson
Photographic telescope" was taken to
Japan last year by Mr. Burckhalter.
fitted with his own design for expos
ing the plates, but the journey was
fruitless Gas everybody knows) by rea-
son of clouds. Attorney w. w. Pier
son furnished the money for the ex-
petition.
Burckhalter's method of photograph
in e nj or o
short exposure time for the fright in
ner corona, and long exposure for the
faint outlying streamers on one end
the same plate. To do this he has a
specially constructed plate holder, con-
tanning a revolving cam shaped dia-
phragm, the centre of which is ar
ranged to be coincident with the con-
tour of the suns image. When the
plate is exposed this diaphragm is rap
idly rotated by clockwork, thus per-
hitting the outer portion of the plate
to receive impressions during the
whole time of exposure, while the cen
trail portions occupied by the bright
corona) are only exposed to the image
for certain fraction of the whole
time.
Experience in cOronal photography
has shown that a plate exposed for one
or two seconds will give a sharp pic
ture of the inner corona, and no out
side streamers, while in a plate expos
ed long enough to portray the extern
sions, all of the inner detail is blOtted
out, or over exposed.
On Mr.. Burckhalter's plates he hopes
| to obtain perfect representations of
the eclipse, as it would appear to
trained eye, with polar rays and all the
closer details shown as distinctly as
the equatorial streamers and on
| the same plate. If this can be done,
| it will be a wonderful advance in
eclipse photography, because hereto
| fore it has only been possible to obtain
| a correct representation of any observ-
ed eclipse by combining the results OF
| many photographs (Of different ex-
posture times) into a more or less UNI
satisfactory drawing.
| At the station Mr.. Burckhalter will
need the services of four assistants.
He hopes to obtain these without diff
Guilty. In India there are number of
army posts, where are stationed many
officers of Her Majesty's service, all OF
| them we'll educated and trained in the
work of observing. 1t has been stated
that willing volunteers will be found
| competent to handle all the scientific
apparatus that can possibly be trans
ported to India for the eclipse.
The probable station to be occupied
by the Chabot party is on the west
coast of India, in the Deccan, and about
| 25O miles south of Bombay. At this
point Mr.. Burckhalter calculates that
| the eclipse will last for two minutes
and seven seconds. Totally will come
| on at l o'clock in the afternoon Cor at
| 8 O'Clock a. m. of Greenwich time) at
which time the altitude of the sun
above the horizon will be in the neigh
borhood of fifty degrees. The path OF
totality in this eclipse extends for a
length of about 1000 miles across India
with a width of about so miles for the
shadow path. The meteorological con-
ditions are particularly favorable, and
/ it will be an exceedingly untOward
j chance that robs the ambitious astron-
omers of clear weather during this
eclipse.