THE ELECTRIC TELEGRAPH AS APPLIED TO ECLIPSES OF THE SUN.
Amongst the auxiliary agencies which have been brought into use in
recent years, to enable astronomers the better to carry out systematic
observations of eclipses of the Sun, the electric telegraph occupies a
place which may hereafter become prominent. As it is not likely that
this little book will fall into the hands of any persons who would be
able to make much use of telegraphy in connection with eclipse
observations, it will not be necessary to give much space to the matter,
but a few outlines will certainly be interesting. When the idea of
utilising the telegraph wire first came into men's minds, it was with
the object of enabling observers who saw the commencement of an eclipse
at one end of the line of totality, to give cautionary notices to
observers farther on, or towards the far end, of special points which
had been seen at the beginning of the totality, and as to which
confirmatory observations, at a later hour, were evidently very
desirable. It is obvious that a scheme of this kind depends for its
success upon each end (or something like it) of the line of totality
being in telegraphic communication with the other end, and this involves
a combination of favourable circumstances not likely to exist at every
occurrence of a total eclipse, and in general only likely to prevail in
the case of eclipses visible over inhabited territory, such as the two
Americas, Europe, and parts of Asia. This use of the telegraph was, I
think, first proposed as far back as 1878, by an American astronomer, in
connection with the total eclipse of that year. His proposal fell upon
sympathetic ears, with the result that arrangements were concluded with
the Western Union Telegraph Company of North America for the expeditious
forwarding of messages from northern stations on the eclipse line to
southern stations. Some attention was being given at that time to the
question of Intra-Mercurial planets, and it was thought that if by good
fortune any such objects were unexpectedly found at the northern
station, and observers at a southern station could be advised of the
fact, there might be a better chance of procuring an accurate and
precise record of the discovery. As it happened, nothing came of it on
that occasion, but the idea of utilising the telegraph having once taken
possession of men's minds, it was soon seen what important possibilities
were opened up.
The want of telegraph organisation curiously made itself felt in the
Egyptian eclipse of 1882. It is stated in another chapter of this work
that during the total phase a comet was unexpectedly discovered. Now
comets sometimes move very rapidly (especially when they are near the
Sun), and had it been possible to have warned some observer to the E. of
Egypt to look out for this comet, and had he seen it even only a couple
of hours after it had been found in Egypt, some data respecting its
position might have been obtained which would have permitted a rough
estimate being formed of its movement through the heavens. Such an
estimate might have enabled astronomers to have hunted up the comet at
sunset or sunrise on the days immediately following the eclipse. As it
happened, however, the comet was not seen again in 1882, and, so far as
we know, may never be seen again.
It was not till 1889 that a complete organisation of a telegraph service
in connection with an eclipse was accomplished. The eclipse of January 1
of that year began in the Pacific and the line of totality touched land
in California, passing across North America to Manitoba. The first
Californian station was at Willows, and was occupied by a party from
Harvard College Observatory, who were supplied with an unusually
complete equipment of photographic apparatus, together with a large
camera for charting all the stars in the neighbourhood of the Sun, so as
to detect an Intra-Mercurial planet if one existed. The telegraph scheme
which had to be worked out was somewhat complicated, and one of the
chief actors in the scene has furnished a fairly full account of what
was done. First of all, a complete list of the instruments and of the
work proposed to be done by them had to be prepared. The weather
probabilities being everywhere very unsatisfactory, there was a
possibility of all degrees of success or failure, and one thing which
had to be prearranged for each station was a cypher code which should be
available for all the likely combinations of instruments, weather and
results. It was found that about one hundred words would suffice for the
necessary code, including words which would indicate in a sufficiently
precise manner the position of any new planet which a photograph might
disclose.
The following, being a part of the code prescribed for use at Willows,
will serve to indicate the nature of the whole scheme:--
_Africa_, Perfectly clear throughout the whole eclipse.
_Alaska_, Perfectly clear during totality.
_Belgium_, Clear sky for the partial phases, but cloudy for totality.
_Bolivia_, Entirely cloudy throughout the whole eclipse.
_Brazil_, Observed all the contacts.
_Bremen_, Observed three of the contacts.
_Ceylon_, Made observations on the shadow-bands.
_Chili_, Observed lines of the reversing layer visually.
_China_, The Corona showed great detail.
_Cork_, Obtained 40-50 negatives during totality.
_Corsica_, Obtained 50-60 negatives during totality.
_Crimea_, Obtained 60-70 negatives during totality.
_Cuba_, Observed a comet.
Upwards of twenty codes were prepared for the like number of stations,
and the observers were to report their results at the earliest possible
moment. On a rehearsal of the programme the thought occurred that the
sending and reception of so many cypher messages in the ordinary course
of business might lead to delays which would be productive of serious
inconvenience, and that the success of the whole scheme could be only
well assured if a special wire, in direct circuit from New York to the
eclipse stations in turn, could be dedicated to the work. Thanks to the
liberality of the Western Union Telegraph Company this privilege was
secured, and a branch wire was led across from the Company's New York
office to the office of the _New York Herald_, which journal had
undertaken to be responsible for the non-astronomical part of the
business.
Mrs. Todd gives the following account of the final arrangements, and of
how they began to work when the moment for action arrived:--"From San
Francisco every California observer was within easy telegraphic reach,
and the wire thus extended by direct circuit to each eclipse station in
turn. From the editorial rooms of the _Herald_ Professor Todd was in
immediate communication with any observers whom he chose to call. As
previously intimated, arrangements had been made with the Harvard
astronomers at Willows to receive their message first and with the
utmost despatch, in order to test the feasibility of outstripping the
Moon. Shortly before 5 o'clock in the afternoon despatches began to come
in. Of course a slight delay was unavoidable, as the observers at the
various stations were some rods distant from the local telegraph
offices, and it would take a few minutes after the eclipse was over to
prepare the suitable message from the cypher code. On the astronomer's
table in the _Herald_ office were a large map and a chronometer. The
latter indicated exact Greenwich time, and the former showed the correct
position of the Moon's shadow at the beginning of every minute by the
chronometer. In this way it was possible to follow readily the precise
phase of the eclipse at every station. About the rooms and accessible
for immediate use were arranged the cypher codes pertaining to the
several stations and other papers necessary in preparing the reports for
the press. Everything being, as was supposed, in working order, New York
about a quarter of an hour before totality commenced inquired of Willows
the state of the weather. The answer was that the sky was getting dark,
and that there were no clouds anywhere near the Sun. At that time the
Moon's shadow was travelling across the open waters of the Pacific. It
rapidly rushed along; totality came and went at Willows; a two minutes'
glimpse of the Corona was had, and the Corona swept rapidly eastwards.
After a brief interval Professor Pickering sent off from Willows a
telegram which began--"_Alaska_, _China_, _Corsica_," and then the
connection failed. The break was located somewhere between California
and Utah, and more than half an hour elapsed ere the circuit was
re-established, and the rest of the message received. The remainder of
the thrilling incidents of that eventful day cannot possibly be better
told than in Mrs. Todd's crisp and striking language[111]:--
"During this interval the lunar shadow, advancing over Montana and
Dakota, had left the Earth entirely, sweeping off again into space.
Still, however, the prospect that the telegraph might win the race was
hopeful. Had New York been located in the eclipse path as well as
Willows, with both stations symmetrically placed, the total eclipse
would have become visible at New York about an hour and a quarter after
the shadow had left California. Thus there was time to spare. Having
recovered the wire, Professor Pickering's message was completed at
10h. 36m. [G.M.T.], the cypher translated, and the stenographer's notes
were written out and despatched to the composing-room six minutes later.
The "copy" was quickly put in type, and the hurried proof handed to
Professor Todd at 10h. 50m., exactly an hour of absolute time after the
observations were concluded. Had the Moon's shadow been advancing from
California toward New York, there was still a margin of several minutes
before the eclipse could become total at the latter place. In point of
fact, while the proof sheet of the first message was being read, the
lunar shadow would have been loitering among the Alleghanies. Man's
messenger had thus outrun the Moon. The telegraphic reports of the other
astronomers were gradually gathered and put in type, and the forms of
the _Herald_ were ready for the stereotyper at the proper time, some
two hours after midnight. At 3 o'clock a.m. the European mails closed,
and the pouches put on board the steamship _Aller_ carried the usual
copies for the foreign circulation. Within twenty-four hours after the
observations of the eclipse were made near the Pacific coast, the
results had been telegraphed to the Atlantic seaboard, collected and
printed, and the papers were well out on their journey to European
readers."
The foregoing narrative will make amply clear the future possibilities
of telegraphy as a coadjutor of Astronomy in the observation of total
eclipses of the Sun. And if the will and the funds are forthcoming, the
eclipse of May 28, 1900, will afford an excellent opportunity of again
putting to the test the excellent ideas of which our American friends
worked out so successfully ten years ago. The zone of totality in that
eclipse passing as it will through so many of the densely populated
Southern States of North America, and then through Portugal, Spain, and
Algiers, great facilities will present themselves for telegraphic
combinations, if political and financial difficulties do not interfere.
FOOTNOTES:
[Footnote 111: There is a want of uniformity in Mrs. Todd's
references to times which I have not thought it necessary to put
straight. "Greenwich Mean Time," "Eastern U.S. Standard Time," and
"Pacific Time," are all severally quoted in happy-go-lucky
confusion.]