plate, there are three major inscriptions in the central dial. The
outermost states _Circulus horarius Soli_, _Lunae_, _Fixis_, _Nodis_,
_Aestuique marino communis_ (the hour circle, common to the sun, the
moon, the fixed stars, the nodes and to the sea tide). This inscription
is divided into four parts by the insertion of four divisions for the
day into canonical hours: [_Horae_] _Nocturnae_ (night hours);
_Matutinae_ (morning hours); _Diurnae_ (daytime hours) and _Vespertinae_
(evening hours).
The next section of the central dial is inscribed
_Intumescite--Detumescite_ (rise and fall of the tides) repeated at
intervals of approximately every six hours. Within the next section is
the following inscription, inscribed continuously around the ring:
Lege fluunt, refluunt, dormitant hac maris undae: Ad Phoebi et
Phoebes concordia iussa moventur Aequora; discordi iussu
suspensa quiescunt.
Translated, this is:
By this law the sea waves ebb and flow and lie dormant: When
Phoebus and Diana agree in their commands, the waters are
moved; when they disagree, the waters lie silent.[16]
Within the central boss of the dial plate, the name of the maker is
inscribed:
Bvrghesio Doctore, et Bertolla Limatore Annaniensibvs*
Translated, this is:
[By] Doctor Borghesi and Bertolla, mechanician citizens of
Anauni.
INDICATORS IN THE FRONTISPIECE
There are 12 windows in the frontispiece, through each of which appears
an indication relating to time. Beginning at the top of the frontispiece
of the dial, the first opening occurs on the breast of the imperial
eagle. This indicates the dominating planet, represented by its symbol,
and its house.
The opening in the eagle's left claw, labeled "Lit. Dom." is the
dominical letter. The first seven days in the month of January are each
assigned one of the letters _a_ through _g_ in order of appearance. The
letter which coincides with the first Sunday within this period is
called the dominical letter, and it serves for the following year. In
leap year, two letters are required, one to February 29th and the letter
next proceeding for the remainder of the year. This letter is used in
connection with establishing the date of Easter Sunday. The date of
Easter regulates the dates of the other movable feasts.
The eagle's right claw is labeled "Cyc. EpEC" and represents the epact,
or the age of the moon on January 1st. It serves to find the moon's age
by indicating the number of days to be added to each lunar year in order
to complete a solar year. Twelve lunar months are nearly 11 days short
of the solar year, so that the new moons in one year fall 11 days
earlier than they did the preceding year. However, 30 days are deducted
as an intercalary month since the moon has made a revolution in that
time, and the remainder, 3, would be the epact.
Below the imperial eagle two winged cherubs support a riband with three
indictions of the Julian period. This period of 7980 years is the
product derived from multiplying together the sums of 28, which
represents the cycle of the sun; 19, representing the cycle of the moon;
and 15, which represents the Roman indiction. The Julian period is
reckoned to have begun from 4713 B.C. so that the period will be
completed in A.D. 3267. The first of the three openings is marked "Ind.
Rom." or "Roman indiction," which was an edict by the Emperor
Constantine in A.D. 312, providing for the assessment of a property tax
at the beginning of each 15-year cycle. It continues to be used in
ecclesiastical contracts. The second opening, which occurs immediately
below the eagle, is marked "Cyc. Sol." (cycle of the sun). This cycle
takes a period of 28 years, after which the days of the week once again
fall upon the same days of the month as they did during the first year
of the former cycle. There is no relationship with the course of the sun
itself, but was invented for the purpose of determining the dominical
letter which designates the days of the month on which the Sundays occur
during each year of the cycle. Since cycles of the sun date from 9 years
before the Christian era, it is necessary to add the digit 9 to the
digits of the current year and then divide the result by 28. The
quotient is the number of cycles which has passed, and the remainder
will be the year of the cycle answering to the current year. The third
opening on the riband is labeled "Num. Aur." (golden number). Meton, an
astronomer of Athens, discovered in 432 B.C. that after a period of 19
years the new and the full moons returned on the same days of the month
as they had before, and this is called the cycle of the moon. The Greeks
were so impressed with this calculation that they had it inscribed in
letters of gold upon stone, hence the golden number. The First Council
of Nicaea in A.D. 325 determined that Meton's cycle was to be used to
regulate the movable feasts of the Church.
Immediately above the chapter rings is an opening through which the orb
of the sun is visible.
THE CHAPTER-RING ASSEMBLY
In a separate chapter in his second volume, entitled "Descriptio
Authomatis Summa totius Operis Mechanici" (Description of the
Automaton--Summary of the Complete Mechanism), Father Borghesi provided
a description of the functions of the various indicators, prefixing it
with the short poem shown in figure 18. He then continues:
In the middle of the frontispiece, as at the center of the
universe, the terraqueous globe of the week revolves, with a
daily motion turning from right to left, bringing with it from
the round window the coming day and at the circumference the
circle of hours common to the sun, to the moon, to the fixed
stars, to the head and tail of the dragon, and to the raging
sea.
The second circle revolves the synodic-periodic measure of the
raging sea, the days of the median lunar-synodic age, the signs
and individual degrees of the signs of the distance of the moon
from the middle of the sun within the time of 29 terrestrial
revolutions, hours 12.44.3.13. This circle revolves likewise
from right to left around the center of the earth. In this
second circle, another little orb revolves, bringing with it
the epicycle of the moon, in which the little circle of the
moon (whose illuminated middle always faces towards the sun),
running from left to right through the signs of the anomaly;
within 13 revolutions of the earth, hours 18.39.16. It descends
from apogee to perigee and in just as many others it returns
from perigee to apogee, to be carried down thus to true, back
and front from the longitude and distance from the sun and from
the middle of the earth.
The third circle (on which I have tried to indicate
astronomically-geometrically in their places, the degrees of
lunar latitude both in the south and in the north, and some
fixed stars, those, namely, which can be separated by us from
the moon which goes between) from left to right turns around
the center of the earth, stretching out the head and tail of
the dragon, on the inside above the second circle for noting
and measuring the sun (but I should rather say the earth), and
the eclipses of the moon, within 346 revolutions of the earth,
hours 14.52.23.
The fourth circle, in which the heaven of the fixed stars,
reduced to the correct ascent of our times, the signs of the
zodiac and the individual degrees of the signs, the months of
the year and the single days of the month can be seen, likewise
makes its journey around the earth from left to right in 365
terrestrial revolutions, hours 5.48.56.; that is, within a
median astronomical year. Above this annual orb, the sun, in
its small epicycle, gliding through the 12 signs of the
anomaly, within the space of 182 terrestrial revolutions, hours
15.6.58., from left to right, falls from apogee to perigee;
and, within the same time, rises from perigee to apogee, and
brings with it, the index, namely its central radius, inhering
to the axis of the equatorial orb and cutting the four greatest
circles from the center.
When the sun has been moved around, Iris shows from six windows
the era, that is, the current year. Two winged youths take
their place next to Iris, carrying the Julian period: namely,
the Roman indiction, the cycle of the sun and the golden
number, on a leaf of paper held between them. The imperial
eagle stands out on top (as if added to the frontispiece)
carrying on its breast the dominating planet and in its talons
the ecclesiastical calends (that is, the dominical letter and
the epact).
ATTACHMENTS FOR ADJUSTMENT
Two attachments, in the form of small superimposed dials are situated at
the base of the dial plate, at either side and immediately below the
fourth chapter ring. In his second volume, Father Borghesi stated that
they "are not moved from inside the clock, but the one at the right
[inscribed _concitat_ and _retardat_] serves for loosening
[accelerating] and tightening [retarding] time; that is, the reins of
the perpendicular."
In other words, the purpose of this attachment is for adjusting the
pendulum to make the clock operate fast or slow. The second attachment,
which appears at the left, and which is inscribed "Claudit" (close) and
"Aperit" (open) serves the purpose of "... preparing the mechanism in a
moment, as swiftly as you wish, for sustaining the astronomical
experiments of which you will hear later; when these things have been
done, it restores the mechanism to its natural motion at the same
speed."
This adjustment relates to the final section of Father Borghesi's second
book, entitled "Chronologo-Astronomicus Usus Authomatis"
(Chronological-Astronomical Use of the Automaton), which is translated
from the Latin in its entirety:
With one glance at this automaton, you can quickly answer these
questions: What hour the sun shows, the moon, any fixed star,
the head and tail of the dragon. Is the sea swelling with
periodic heat [at high tide?] or is it deflated [low tide], or
quiescent? How many days is it from mean new moon or full moon?
By how many signs and degrees is the moon distant from the sun,
and from its nodes? What sign of the zodiac does the sun
occupy, the moon, the head and tail of the dragon? Is the sun
or the moon, in apogee or perigee, ascending or descending?
What is the apparent speed of the sun and of the moon? What is
the apparent magnitude of the solar and lunar diameter, and of
the horizontal parallax of the umbra and penumbra of the earth?
What is the latitude of the moon? Is it north or south? Does
the moon hide [occult eclipse] any of the fixed stars from the
earth dwellers, and which of these does it obscure? Is there a
true new or full moon? Is the sun in eclipse anywhere on earth?
What is the magnitude, and the duration of this eclipse, with
respect to the whole earth? Can it be seen in the north or in
the south? Is the moon in eclipse? Total or partial? Of what
magnitude, etc.? What limb of the moon is obscured? How many
years have passed from a given epoch? Is this year a leap year,
or a common year--first, second, or third after leap year? What
is the current month of the year, and what day of the month and
of the week? Which of the planets is dominant? What days of the
year do the various feasts fall on, and the movable feasts
during the ecclesiastical year? And many other similar
questions, which I pass over here for the sake of brevity.
Besides, this device can be so arranged for any time
whatsoever, past or future, and for the longitude of any
region, and can be so manipulated by hand, that within the
space of a very short time there can be provided in their
proper order, the various orbits of the luminous bodies, their
alternating eclipses, as many as have taken place through the
course of many years, or even from the beginning of the world;
or those that will be seen as long as the world itself shall
last, with all their attendant circumstances (year, month, day,
duration, magnitude, etc.). All these can be seen with great
satisfaction of curiosity and of learning, and hence with great
pleasure to the soul. In the meanwhile, the little bells
continually play, at their proper, respective times. So that,
all exaggeration aside, a thousand years pass, in the sight of
this clock, as one day!
I am aware of your complaints, O star-loving reader--that my
description is too meager and too succinct. Lay the blame for
this on those cares, hateful both to me and to you, more
pressing, which forbid me and deprive you of a methodical
explanation of the work.
THE CLOCK MOVEMENT
Father Borghesi specified that the entire mechanism was equal in weight
to a seventh part of a _Centenarii Germanici_, a Germanic hundredweight.
This is probably the Austrian centner which is equivalent to 123.4615
pounds. Therefore, the clock mechanism weighs approximately 17.6 pounds.
The clock operated for a hundred days and more at a single winding,
according to Father Borghesi, and by means of a pendulum with a leaden
bob weighing 60 Viennese pounds, attached at a height of 5 feet. Father
Borghesi stated the weight of the pendulum to be 60 _librarum
Viennensium_, but the Viennese libra does not appear among the weights
of the Austrian Empire. However, using the average libra, an ancient
Roman unit of weight equal to 0.7221 pound, it may be assumed that the
driving weight should be approximately 45 pounds.
Father Borghesi, however, does not venture to provide any description
whatsoever of the movement of his second clock in his book. He gave the
following reasons:
But beyond this, I entirely omit [a description of] the further
apparatus of the very many wheels, etc., inside the clock which
carry on its functions, lest I become too verbose for some
persons. To explain more thoroughly the internal labyrinth of
the entire mechanism, from which the movement of the circles or
heavens, etc., are derived, would seem to entangle in too many
complicated perplexities.... Therefore, that I might not delay
longer, and perhaps to no purpose, I have thought it better to
leave the whole work to the proportionate calculus of the
arithmeticians and the technical skill of mechanics. If they
have any desire to construct a similar mechanism, they will
follow the aforesaid motions of the heavens, etc., not only by
one means alone but by many, more swiftly through thoughtful
study than by any amount of instruction.
For whoever is well versed in the theory of calculus and sets
to work at any given project, will discover any desired motion
by a thousand and more ways, by one or another gearing of
wheels; which an industrious mechanic will carry out in
actuality and without too much difficulty. Nor is there any
reason for anyone to be discouraged, so long as he is not
disgusted by the amount of labor for there is nothing truer
than the old saying "The favorable gods grant everything to the
assiduous laborer."
Nay, further, even this little work itself can be improved on
and surpassed by new inventions. Otherwise that other old
adage, almost as old as the world, would prove false, "What you
have found already done, you can easily repeat, nor is it
difficult to add to what has already been invented." Relying on
this principle, I have already conceived some new things to be
added to the present little work.
[Illustration: Figure 17.--MOVEMENT OF BORGHESI CLOCK viewed from the
right side, with details of chiming mechanism.]
THE BELLS
There is a discrepancy between Father Borghesi's written description in
his second book of the number of bells and those which currently exist
in the clock. At the present time, there are two sets of bells attached
to the upper part of the movement. While Father Borghesi indicated that
there were two sets of bells in the clock, he described the first set by
stating that:
... there are three bells inside the clock: The largest, when
struck by a little hammer at each mean new moon, signifies the
new moon. The smallest indicates in the same way the full moon
at the time of the mean full moon, by automatic sound. When on
the equatorial earth, the sun appears anywhere in eclipse, two
bells (the largest and the medium) sounding together
automatically, announce that eclipse at the time of the mean
new moon. (I think it is evident that eclipses of the sun occur
at new moons and eclipses of the moon at full moon.)
When the moon is eclipsed, the smallest and the medium bells,
simultaneously and automatically, announce the event to the ear
at the time of the mean full moon. Besides, at the proper time
and automatically, the largest of these bells announces the
current solar hour and the smallest bell strikes the quarter
hours.
In the clock today, the first set consists of a smaller bell fixed
within a larger one. It is presumably these bells that indicate the
eclipses and also strike the hours and quarter hours. A pull cord
attached to the striking mechanism repeats the current hour and quarter
hours at will. The second set consists of nine meshed bells struck with
individual hammers operated by means of a pinned cylinder as in a music
box. On the hour, the chimes play one of two melodies, which may be
changed at will. While not identified, these appear to be Tyrolean folk
melodies. The largest of this set of bells is dissimilar to the other
chimes, and may be the third bell described by Father Borghesi to
signify the new moon.
CHRONOGRAMS
One of the most curious aspects of the second clock produced by Father
Borghesi and Bertolla, as well as of the second published volume, is the
presence of chronograms which occur repeatedly on the clock dial and
throughout the _Novissimum Theorico-Practicum Astronomicum Authoma_ from
the title page to the end of the book. Interestingly enough, Father
Borghesi did not utilize this device even once in his first little book.
[Illustration: Figure 18.--A CHRONOGRAM in the text of Father Borghesi's
second volume, indicating the year 1764. The poem is translated as: "In
the Mount of 'Anauni,' the inscrutable heavens are led, You learn from
these all the labors of the sun and the moon. Here you are shown and
hear the conjunction of the moon: And a bell brings to the ears by its
sound, all eclipses."]
Webster defines a chronogram as an inscription, sentence, or phrase in
which certain letters express a date or epoch. The method used by Father
Borghesi for forming chronograms was a simple one. He used combinations
of uppercase and lowercase letters in two sizes in the inscriptions on
the clock dial and in his writings. At first this curious combination in
the inscriptions on the dial plate was a source of considerable
speculation. The extremely fine quality of the engraving and artistry
was such that these combinations could only be deliberate in nature and
not the accidental whims or accidents of the engraver. Accordingly, they
must be chronographic in intention. Such proved to be the case.
Borghesi used the larger size of uppercase letters to form the
chronogram, and each chronogram was complete within a phrase or line. He
accomplished this by using for this purpose those letters of the
alphabet which form the Roman numerals. The uppercase letters found
within words are copied off in the order in which they appear in the
inscription or phrase. These are then converted into their numerical
equivalents, and totaled. Taking the uppermost inscription on the clock
dial as the first example:
FranCIsCVs I sIt pLan. DoMInator aeternVs
The letters which are intended to form the chronogram are:
C I C V I I L D M I V
100 1 100 5 1 1 50 500 1000 1 5
These figures added together total 1764.
The second inscription on the clock dial which forms a chronogram is
LaVs saCrosanCtae TrIaDI VnI Deo, et DeIparae
L V C C I D I V I D D I
50 5 100 100 1 500 1 5 1 500 500 1 = 1764.
The third inscription required a little more planning, because of its
greater length. Accordingly, Father Borghesi divided it into nine parts,
each of which is separated from the other by means of asterisks. Each of
the nine parts of the inscription formed a chronogram which, in every
instance, totals to the date 1764, the year in which the second clock
was completed. The same procedure was followed with the inscriptions in
the lower left and the lower right corners of the dial as well as with
the maker's inscription within the central disk. This inscription is
BVrghesIo DoCtore, et BertoLLa LIMatore AnnanIensIbVs
V I D C L L L I M I I V
5 1 500 100 50 50 50 1 1000 1 1 5 = 1764.
The inscriptions within the chapter ring are not utilized for
chronograms, however. It is apparent that Father Borghesi was required
to make a most careful selection of the texts for his inscriptions in
order that none of the phrases included any additional letters which
formed Roman numerals than would total to the date he desired to
indicate, namely, 1764. Where it was necessary, he employed an asterisk
to separate parts of texts so that each would produce the same total.
Any letter that did not form a Roman numeral, even if capitalized or
used in a larger size, did not interfere with the formation of the
chronograms.
In spite of his ingenuity in designing a text which would include only
such of the letters representing the Roman numerals which would provide
the chronograms for 1764, Father Borghesi experienced some difficulties,
particularly in place names. He accordingly changed them in order to
avoid the inclusion of letters that would have disturbed his totals.
Examples are MEGGL instead of MECHL, which had an extra C, and RVNNO
instead of RVMO, which had an extra M.
PUBLISHED DESCRIPTION OF THE SECOND CLOCK
When the clock had been completed and proved to work successfully,
Borghesi once more reduced a description of the clock and its function
to published form in a second little volume published by Monauni. This
second work was also in Latin, the title of which is translated as _The
Most Recent Theoretical-Practical Astronomical Clock According to the
Equally Most Recent System of the World_. As with his first book, Father
Borghesi devoted a number of pages to a preface addressed to the reader,
which is translated from the Latin:
This mechanical instrument was far from being ready for public
notice. A great deal of time and work remained to produce a
machine of this new system from the very foundations; then, by
a most accurate calculation to bring the motions of many wheels
up-to-date with the most recent astronomical observations; and,
finally, to fashion it with the craftsman's file, often enough
with a weary hand. All this work I had performed eagerly, so
that, while in my room, I might contemplate leisurely, both day
and night, the true face of the heavens and the seas unobscured
by clouds, even though I had no astronomical equipment. But,
then I remembered that, in my book on the first clock, I had
promised a description of a new (at least, as far as is known
to me) clock. Moreover, friends with astronomical interest, who
took part in the oft-repeated astronomical experiments
concerning this clock, persuaded me that the intellectual world
would enjoy having a greater knowledge and a description of
this work. However, it was not only the promises nor the
desires of many which moved me to write this work, but I also
thought it was necessary to set forth, before the description
of the clock, an exposition of the astronomical system
according to which this clock was constructed, so that the
complete work would be evident to all. I was concerned about
making this timepiece more acceptable and more understandable
to those people who are far distant and unable to see it, so
that this present exposition would obtain credulity among all.
I could find no better method than to set forth for the reader
the theory of the universe which I figured out after many
sleepless nights.