DEL ARBOL, that at its last session the Conference resolved, with
singular unanimity, that it was expedient to adopt "a universal day
for all purposes for which it may be found convenient, and which shall
not interfere with the local or other standard time where desirable."
The Chair would politely suggest that the subject now under
consideration is the adoption of the proposition recommended by the
Conference at Rome, and which has been presented here by the Delegate
of Sweden, Count LEWENHAUPT.
Mr. RUIZ DEL ARBOL, Delegate of Spain. My proposition is to abstain
from the adoption of any one meridian, and that we leave the matter to
some other Congress, organized with the special object of regulating
this question.
Commander SAMPSON, Delegate of the United States. Mr. President, as
near as I can follow the Delegate of Spain, he seems to be under the
apprehension that by the adoption of the universal day, which has been
proposed here, we should either gain or lose time in our chronology;
that we should skip 12 hours, more or less. But, of course, that is
not the case. Any event which has occurred, or which will occur, at
the time of the adoption of the universal day will be expressed just
as exactly with reference to time as if the time had been calculated
from the beginning of the Christian era. There will not only be no
confusion, but it seems to me the adoption of the universal day will
tend to avoid confusion hereafter, because confusion must exist where
we have so many standards of time. Now, if any event which is taking
place, or has taken place at any past time in the history of the
world, is referred to the prime meridian, or is expressed in the time
of any locality or of several localities, these times will all be
different. The adoption of the universal day is to avoid any
difficulty of that sort, and any event which has transpired will, when
expressed in the time of the universal day--that is, according to the
universal method--represent exactly the interval of time which has
elapsed since the beginning of the Christian era. Nothing is gained or
lost.
General STRACHEY, Delegate of Great Britain. It seems to me that the
Congress having accepted the resolution to which reference was made a
little while ago, adopting the universal day, it is incumbent upon us,
in the nature of things, to determine when that universal day shall
begin. The resolution presented by the Delegate of the United States
proposes to define how that universal day shall be reckoned; that is,
when it shall begin and how its hours shall be counted.
It was explained by him that the difference between his proposition
and the proposition made at Rome consisted in altering the time of the
commencement of the so-called universal day from noon at Greenwich to
the commencement of the civil day. Certainly what Commander SAMPSON
just said is perfectly true. The adoption of this so-called universal
day will not interfere in the smallest degree with any purpose for
which time is employed in civil life. The two objects are entirely
distinct. It is obvious that the conception of the necessity of having
a universal day has arisen from the more clear conception of the fact
that time on the globe is essentially local; that the time upon any
given line (supposing it to be a meridian) is not the time at the same
moment on either side of that line, however small the departure from
it may be; and for scientific accuracy it has, therefore, been thought
desirable to have some absolute standard to which days and hours can
be referred. Up to the present time it has been the practice to say,
in an indefinite way, that an event happened, say, on the 1st of
January at 6 o'clock in the morning, and such a statement of the time
has been considered sufficient; but, in truth, this does not
completely describe a definite epoch of time, for if the event
occurred at Madrid and was so reported, that report would not
designate the same moment as a report of an event which was described
to have occurred at precisely the same date and hour at Greenwich, or
Rome, or Washington. What is required and desired is that we should
have an absolute and definite standard for reckoning events of a
certain description, for which complete precision is desirable. I
consider, therefore, that the Delegate of Spain leads us astray in the
proposition which he has offered, by which he virtually proposes to
nullify the resolution already adopted. We have already decided that a
universal day was expedient, and it is for the Conference to settle
now when that universal day shall begin.
Mr. RUIZ DEL ARBOL, Delegate of Spain. I understand that the
consequences, perhaps, would not be troublesome at first; but who can
look into the future and say, if we take the meridian of Greenwich as
the standard of time, what difficulties we may be driven into? Every
country will be obliged to count both ways. They will have to use
civil time and universal time. Perhaps all countries may get
accustomed to this radical change sooner or later, but we cannot
foresee the difficulty now. I have here a treatise (a book) on
"Analytic Chronology," showing the rules by which to bring into accord
different dates of different calendars and eras, and I do not know how
they would be affected by this universal time; but it is unnecessary
for me to speak of that, as I think you are acquainted with the
subject.
Mr. JUAN PASTORIN, Delegate of Spain. The Congress has already come to
very important decisions on the subject of the reckoning of longitude,
and it will also certainly approve to-day those which have just been
submitted on the subject of the universal day.
I say certainly, because the result of the former votes being already
known, it cannot be doubted on which side the majority will be, and
because, from a scientific point of view, having chosen Greenwich as
the prime meridian for the calculation of longitude, and having
decided to reckon longitude in two directions from zero hours to
twenty-four hours, with the sign plus towards the east and minus
towards the west, it will be advantageous to make the civil day of
Greenwich coincide with the universal day, if we would have an easy
formula for passing from local to cosmic time.
So many of the resolutions submitted to the Congress by Mr. RUTHERFURD
having been approved one after another, the plan that our colleague
has carefully studied will be accepted in its entirety; but it will be
impossible for the Conference to know in all their details other plans
which, perhaps, would not be less worthy of attention.
Is the resolution adopted by a majority of the Congress the best?
Should we reach the end of the reform in complete harmony with the
hopes of all the governments represented here? On the contrary
hypothesis, it seems to me, that the sessions of this Congress will
only be another step towards that reform, but not the reform itself.
If the majority of the Congress, in accordance with the logical
consequence of its work, adopts as the cosmic time the civil time of
Greenwich, that decision will be contrary to the most ancient ideas of
the human race. For many centuries the day has been reckoned as
starting from the east, and the world will not easily abandon the
traditions of its predecessors.
The civil day of the world commences near the anti-meridian of Rome,
Greenwich, or Paris. Therefore it is not natural that one of these
meridians should be chosen as the point of departure of dates.
Really, one phenomenon cannot be the commencement of a series of
phenomena if there is another which precedes it periodically.
If the majority, as is logical, adopts the formula, "cosmic time=local
time-longitude," and applies in the calculation longitude with the
signs plus and minus, according as the longitude is east and west, the
system will be source of frequent mistakes, and those, in their turn,
will be the cause of disastrous accidents, especially on railroads.
Let us take the 31st of December, for instance. It is three o'clock at
a point nine hours east of Greenwich; at the same moment they will
count at Greenwich eighteen civil hours of the 30th of the same month,
after the actual manner of reckoning the civil day, and that civil
time of Greenwich will be the cosmic time.
Apply to the proposed example the formula which I suppose the majority
of the Congress will adopt, and the result will be a negative
quantity, minus six hours--a result not sufficiently comprehensible in
itself, and one that could not be easily applied by the general
public.
Can a majority prevail in questions, such as those we are speaking of,
simply by the force of numbers? The whole world for several centuries
thought that the earth was the centre of our planetary system; in
fact, until an insignificant minority rose against this theory, for a
long time considered by their ancestors indisputable.
I will conclude by expressing my opinion upon the subject with which
the Congress is occupied. My opinion is not new, in spite of its
having been modified in the course of our sitting. The works of our
eminent colleague and indefatigable propagandist, Mr. SANDFORD
FLEMING, the resolution of the Conference at Rome, the valuable
opinions of Messrs. Faye, Otto Struve, Beaumont de Boutiller, Hugo
Gyldén, the scientific work of Monsieur Chancourtois, and the report
which M. Gaspari has just presented to the Academy of Sciences of
Paris are the text upon which I base the simplest and most practical
method of solving the problem, namely, to adopt as the prime meridian
for cosmic time and longitude a meridian near the point at which our
dates change, and to reckon longitude from zero hours to twenty-four
hours towards the west, contrary to the movement of the earth. The
formula would be then: Cosmic time = local time + longitude.
I think that the best way of finding cosmic time in relation to local
time and longitude is to add a quantity to the civil hour of each
point of the globe.
But as the majority of this Congress, so worthy of respect, admits no
modifications of the system which we may call Greenwich, let us lay
aside the question of longitude and consider cosmic time separately.
I have the honor, therefore, to present the following resolutions, and
I ask the Congress to consider them, and to accept them as a means of
compromise:
I. We agree to choose as the prime meridian for cosmic time that
meridian near which the civil day of the world commences, namely, the
anti-meridian of Rome, Greenwich, or Havre.
II. The cosmic day consists of twenty-four hours, and commences at
midnight of the prime meridian.
III. The earth is divided from the initial meridian into twenty-four
hour-spaces, counted in a direction contrary to the movement of the
earth from _0h._ to _24h_.
We shall, then, have the following formula: T = t + R, where R
represents the difference reckoned from _0h._ to _24h_. between the
local time of the prime meridian and the local time of each point of
the globe; T the Cosmic Time and t the local time.
The PRESIDENT. The Chair would ask the Delegate of Spain, Mr.
PASTORIN, whether he offers his resolution as an amendment to that
offered by his colleague, Mr. RUIZ DEL ARBOL.
Mr. RUIZ DEL ARBOL, Delegate of Spain. Mr. Chairman, the amendment
last offered is not intended to interfere with my proposition.
The PRESIDENT then put the question to the Conference upon the
amendment offered by the Delegate of Spain, Mr. RUIZ DEL ARBOL.
Upon a vote being taken, the amendment was lost.
The PRESIDENT. The question now recurs upon the amendment offered by
the Delegate of Spain, Mr. PASTORIN. That amendment runs as follows:
"I. We agree to choose as the prime meridian for cosmic time
that meridian near which the civil day of the world
commences, namely, the anti-meridian of Greenwich or Havre.
"II. The cosmic day consists of twenty-four hours, and
commences at midnight of the prime meridian.
"III. The earth is divided from the initial meridian into
twenty-four hour spaces, counted in a direction contrary to
the movement of the earth.
"We shall, then, have the following formula: F = A + R where
R represents the difference reckoned from 0h. to 24h.
between the local time of the prime meridian and the local
time of each point of the globe; F the cosmic time, and A
the local time."
The PRESIDENT. In order that this amendment may be presented more
clearly to the Conference, I would propose a recess for a few minutes.
If there be no objection, a recess will be taken.
No objection being made, the Conference took a recess.
* * * * *
The PRESIDENT having called the Conference to order stated that,
unless further remarks were presented, the vote would be taken upon
the resolution offered by the Delegate of Spain, Mr. PASTORIN.
No objection being made, the vote was then taken upon the amendment,
and it was lost.
The PRESIDENT. The question now recurs upon the resolution offered by
the Delegate of Sweden, Count LEWENHAUPT, which will again be read.
The resolution is as follows:
"The Conference recommends as initial point for the
universal hour and the cosmic day the mean mid-day of
Greenwich, coinciding with the moment of midnight or the
beginning of the civil day at the meridian 12 hours or 180°
from Greenwich. The universal hours are to be counted from
0 up to 24 hours."
Professor ADAMS, Delegate of Great Britain. Mr. President, I intended
to speak on the resolution offered by the Delegate of the United
States, Mr. RUTHERFURD, but the remarks which I have put together
apply equally well to the amendment to that resolution now offered by
the Delegate of Sweden, which is identical with one of the
recommendations of the Conference at Rome, because, in fact, in my
remarks I discuss these propositions alternatively. Therefore, with
your permission, I will lay before you the observations which I wish
to make.
I beg leave to express my entire approval of the resolution which has
been laid before the Conference by Mr. RUTHERFURD. There is only one
point involved in the resolution which seems to call for or even to
admit of any discussion.
It appears evident that the universal day and date should coincide
with the day and date of the initial meridian. The only question,
therefore, which we have now to decide is, when shall this day of the
initial meridian be considered to commence? And the proper answer to
be given to this question does not appear to me in any degree
doubtful.
In modern times it is the universal practice to reckon dates by _days_
and not by _nights_. The word "day" is used in two different
significations, being sometimes applied to the period of daylight and
sometimes to the period of 24 hours, including both day and night; but
in whichever of these senses the word _day_ is employed, the term
mid-day has one and the same signification, viz., the instant of noon
or of the sun's passage over the meridian. In the present case, where
we are concerned with mean time, mid-day means the instant of mean
noon, or of the passage of the mean sun over the meridian.
Accordingly, the civil day, by which all the ordinary affairs of life
are regulated, begins and ends at midnight, and has its middle or
mid-day at noon.
It appears, then, most natural that the universal day should follow
this example, and should begin and end at the instant of mean midnight
on the initial meridian, and should have its middle at the instant of
mean noon on the same meridian.
I fail, therefore, to see the force of the reasons which induced the
Conference at Rome to recommend that the universal day should commence
at _noon_ on the initial meridian.
The only ground for making this recommendation is that astronomers,
instead of adopting the use of the civil day, like the rest of the
world, are accustomed to employ a so-called astronomical day, which
begins at noon. The advantage thus gained is that they avoid the
necessity of changing the date in the course of the night, which is
the time of their greatest activity; but this advantage is surely very
small when compared with the inconvenience of having two conflicting
methods of reckoning dates, and of being obliged to specify, in giving
any date, which mode of reckoning is adopted. If this diversity is to
disappear, it is plain that it is the astronomers who will have to
yield. They are few in number compared with the rest of the world.
They are intelligent, and could make the required change without any
difficulty, and with very slight or no inconvenience.
The requisite changes in the astronomical and nautical ephemerides
would be easily made. As these ephemerides are published several years
in advance, there would be plenty of time for navigators to become
familiar with the proposed change in time-reckoning before they were
called upon to employ it in their calculations.
I believe that they would soon come to think it more convenient and
natural to reckon according to civil time than according to the
present astronomical time. I am told that this practice is already
universally adopted in keeping the log on board ship. To avoid any
chance of mistake, it should be prominently stated on each page of the
ephemerides that mean time reckoned from mean _midnight_ is kept
throughout.
Whether or not astronomers agree to adopt the civil reckoning, I think
we ought to adopt the instant of midnight on the initial meridian as
the commencement of the universal day.
The relation between the local time at any place and the universal
time would then be expressed by the simple formula:
Local time = universal time + longitude.
Whereas, if the proposition of the Roman Conference were adopted, we
should have to employ the less simple formula:
Local time = universal time + longitude - 12 hours.
In recommending the mean noon at Greenwich as the commencement of the
universal day and of cosmopolitan dates, the Roman Conference refers
to this instant as coinciding with the instant of midnight, or with
the commencement of the civil day, under the meridian situated at 12
h. or 180° from Greenwich. Now, this reference to the civil day and
date on the meridian opposite to Greenwich appears not only to be
unnecessary and to be wanting in simplicity, but it may also lead to
ambiguity in the date, as expressed in universal days, unless this
ambiguity be avoided by making an arbitrary assumption. No doubt the
Greenwich mean noon of January 1 coincides with midnight on the
meridian 12 h. from Greenwich, but with what midnight. What shall be
its designation and the corresponding date given to the universal day?
Shall we call the instant above defined the commencement of the
universal day denoted by January 1 or by January 2? Each of these
dates has equal claims to be chosen, and the choice between them must
clearly be an arbitrary one, and may, therefore, lead to ambiguity.
By adopting Greenwich mean midnight as the commencement of the
universal day, bearing the same designation as the corresponding
Greenwich civil day, all ambiguity is avoided, and there is no need to
refer to the opposite meridian at all.
Those are the ideas I wish to express with regard to the commencement
of the universal day.
I may mention in connection with this subject that Professor
Valentiner is one of the gentlemen who were invited, a week or two
ago, to attend the meetings of this Conference, in order that, if
requested, they might express their opinions from a scientific
standpoint upon the questions before it; but as Professor Valentiner
had to leave Washington before our sessions were at an end, I thought
it would be expedient to ask him for his opinion in writing upon the
matter which is now pending before this Conference. He has written a
letter in German, expressing his opinion. I have caused that letter to
be translated into English, and if the Conference allows me I will
read it.
The PRESIDENT. If there be no objection to the proposition of the
Delegate of Great Britain the letter will be read.
No objection being made, Professor ADAMS continued: It is well known
that Professor Valentiner is an eminent practical astronomer, and I
think that any opinion coming from him on this subject, which
interests astronomers very much, will be considered of great weight.
The letter runs as follows:
CHARLOTTESVILLE, VA.,
_October 12th, 1884_.
HONORED SIR: You had the kindness to ask me for my views as
to the choice of the moment for the beginning of the day. As
I cannot remain longer in Washington, I allow myself thus
briefly to write to you.
When, as in the present case, the object is to introduce
uniformity in the time-reckoning of the astronomical and the
civil world, I am of the opinion that it is the astronomer
only that must give way. For all purposes of civil life one
cannot begin the day in the middle of the day-light--that is
to say, in the middle of that interval during which work is
prosecuted. In general it appears to me natural that the
middle of the day, and not the beginning of the day, should
be indicated by the highest position of the sun which
governs all civil life. In fact, it would in civil life be
simply impossible to bring about a change of date in the
middle of the daylight. For the astronomer there certainly
exist difficulties. His activity occurs mostly in the civil
night, and he, therefore, has to make the change of date in
the midst of his observations; and this difficulty is
increased, since he almost exclusively observes according to
sidereal time, so that often a computation must be made in
order to ascertain whether the observations were made before
or after the midnight or moment of change of date. However,
this difficulty can be overcome by habit, and I believe that
scarcely any doubt will occur as soon as a uniformnity of
expression has established itself through the astronomical
world. As regards the ephemerides, we already employ, in
fact, the beginning of the date at midnight, since the
places of planets and comets, are generally computed for 12
o'clock midnight of Berlin or Greenwich or other places.
But these are points that have themselves long since been
discussed.
I scarcely need to say anything further. I would not
hesitate for a moment to give the preference to making the
change of date take place at midnight, according to civil
reckoning, in order to establish a uniformity with the
customs of civil life.
It, perhaps, may be important to remark that we could not
introduce this change immediately, since the ephemerides are
already computed and published for three or four years in
advance. It would, therefore, be well to fix the epoch of
change of normal dates to some distant time, such as 1890.
I remain, very respectfully yours,
W. VALENTINER.
I may also mention that the practice that prevails among astronomers
at the present time of reckoning the day from noon is by no means
without exceptions. There are very important astronomical tables which
reckon the day from midnight; for instance, in Delambre's Tables of
the Sun; in Burg's, Burckhardt's and Damoiseau's Tables of the Moon;
in Bouvard's Tables of Jupiter, Saturn, and Uranus, and in Damoiseau's
Tables of Jupiter's Satellites, mean midnight is employed as the epoch
of the tables. I may also mention that Laplace, in his Mécanique
Celeste, adopts the mean midnight of Paris as the origin from which
his day is reckoned. Hence there are great authorities, even among
astronomers, in favor of commencing the day at midnight.
General STRACHEY, Delegate of Great Britain. Sir, I observe that a
very eminent American authority is present in this room, I mean
Professor Hilgard. As he was invited to attend the meeting of this
Conference, I suggest that the views of the Conference may be taken,
whether he may not be invited to express his opinion on the point now
under consideration.
The PRESIDENT. With the concurrence of the Conference, the Chair will
be most happy to ask Professor Hilgard to do us the favor to give us
his opinion upon the question now before the Conference.
No objection was made to the proposition of the President.