Wood County reporter. [volume] (Grand Rapids [i.e. Wisconsin Rapids], Wis.) 1857-1923, 1891-08-20
George A. Fargis is the Inventor of
a Device for Recording Star
Transits.
There Will Not be an Error of One
ThOusandth of a Second in
Time.
An Invention Which Will be Exceed
ingly Useful in Determining
Star Movements.

Inc pTOCuCC ldsG year Ol UHe LdGIu
play at st. Francis Xavier's college will be
recalled with pleasure. From recent in
vention of one of the alumni it is evident
that the college trains as well in the
sciences as in the classics. The invention
IS the photo chronograph, which automat-
ically records star transits. 1t is the latest
improvement made in astronomical meth
DDS. and is the work of the Rev. George A.
Fargis, graduate of St. Francis XaVier's
and now an assistant director OF the
Georgetown College observatory, at Wash
ington, D. C.
The trouble heretofore in transit obse1
yations has been the personal equation, y
or inaccuracy made by the eye or ear in
translating the phenomenon of an object
moving over the field of view in tele-
scope into a picture of the same, which
can be measured as fixed object. A pho
tographic plate reduces this inaccuracy to
minimum, and the first experiments to
determine time by photographs of star
transits were made by Professor E. C.
Pickering at Harvard College observatory
IN January, 1889, when it was found that
the probable error of calculation could be
reduced to 003s Further experiments,
but not wholly successful, were made there
In 1888. Professor F. H. Bigelow was at
work on the same idea in Washington
when his experiments were broken off by
his appointment to the eclipse expedition
to West Africa in 1888. Further develop
ment devolged wholly upon the George
town College observatory.
In the New Princeton Review for May,
1887, Professor Charles A. Young, in an
article on Astronomical Photography"
says:
In 1849 Faye suggested that photo
observation, but it is only recently that
any serious attempt has been made to put
the ioea into practice. Pickering in this
country, Lohse in Germany and Won Got
hard in Hungary have all experimental
with more or less success. 1t
may quite possibly work as great revolu-
ton IN the art of meridian observation as
was brought about by the introduction of
the electric break and the chronograph.
Father Fargis thinks he has realized
Professor Young's hopes by his invention,
which will use his own words In describ-
ing.
The transit instrument at the George
town observatory was made In 1874 by
Estel & Son, of Munich. The object glass
is four inches in diameter, with focus
distance of about seventy-eight inches.
The experiments of Professor Bigelow were
made with the instrument by permission
of the college authorities, and at first was
thought he had solved the problem of the
application CT photography to meridian
observation, but the examination of the
results showed radical defect in moving
sensitive plate 1t was decided that the
plate should not move, and hence the ex-
periments of Father Fargis, which have
resulted in the invention of the occuating
bar and the photo chronograph. He de-
cribes it as follows
The apparatus consists of strong brass
collar fitting close to the sliding tube, just
behind the collimating plate by means of
hinge and screw bolt. To this collar is
attached a q shaped soft iron core, with a
coil on one only of the arms, to diminish
weight The naked part of the core is
bent back and up so as to act on the armat
ure from behind The end of the core is
encircled with thin ring of cord to dim
inish the force of the armature stroke
The usual adjustment and connecting
screws are conveniently placed.
"A strip of steel about two millimetres
In width and two-tenths of a millimetre In
thickness is soldered to the armature at
passed through the apertures In the side
of The focusing tube, intended for direct
wire illumination, and stretched across the
retice The coil, armature and occulting
bar or shutter are so fixed to the collar
that, when at rest, the lower edge of the
shutter (cIamp east and transit pointed
south) is parallel to. ana fraction of a
millimetre above the horizontal diameter
of the reticle.
Divested of further scientific details the
device consists of tiny camera fixed to
the eve piece of the transit instrument.
An extra sensitive plate, ~ by 212 inches,
capable of photographing a fourth mag
nitude star with an exposure of one-tenth
of second, is placed. Connection is then
made with a sideral clock relay. When
a star begins its transit the current is
turned on. The occulating car or shutter
falls with the armature, cutting off the
light of the star AG the break the shut
ter rises with the armature, uncovering
the star for one-tenth of second and
dropping again as the current flows.
Mence the negative shows a simple line of
dots or the star trail across the plate.
This can be permanently fixed on the
plate and microscopically measured and
examined"
Father Fargis has made these micro
metric examinations of over two hundred
PHOTOGRAPHIC transits and finds no per-
ceptble trace of any serious error. He
claims that his photochronograpn actually
registers on the sensitive plate to within
the one thousandth part of a second, the
time of transit of star.
The invention is expected to be exceed
ingly useful in the fundamental differ
entail comparisons. IN longitude determl-
nations, in latitude observations, in double
star measurements and for physical obser-
yations in laboratories. The importance
of any method of increased accuracy of
transit observations is fundamental In as
tronomy.
Father Fargis, the inventor of this sim
pie, vet important device, celebrated his
thirtv-seventh birthday recently. He was
born in New York city and, on his fathers
side. comes from an old French family.
He entered st. Francis Xavier's College
while quite young and made the full
course, graduating there In 1873.
Shortly after graduating he joined the
Jesuit order and made his two years no.
vitiate at lie Sault, II, ar Montreal. Thence
he went to the house OF studies OF the So
ciety, near Redemption, England, where
he spent three years. He next passed over
to Louvain, in Belgium, and for two years
attended the University there.
While in Belgium he had the advantage
of training under the famous geologist
Father Renaud, and when he first returned
to New York he gave considerable time to
the geological bra1ch that considers the
microscopical examination of fossils In
rocks. His Investigations of the rhizo-
phods were also important. Since he has
taken up astronomy, however, he has let
oeolons 90 He Is also q fine musician