after another of 7000 stars, and read off their positions
on the graduated circle. But the life of Piazzi supplies
an effective reply to such a criticism. During the course
of the observations he believed that he had found the
long-sought parallax of certain fixed stars that is, the dis-
1 Populare Vorlesungen iiber wissenschaftliche Gegenstande von
F. W. Bessel. Nach dem Tode des Verfassers herausgegeben von
H. C. Schumacher, Hamburg 1848, 21 23; cf. 239 538.
76 III. ASTRONOMY.
placement which the position of the stars must undergo
from the fact that in the course of the earth's annual move-
ment they are observed from widely separated points
of observation. On closer examination, however, he
discovered that it was not the stars but his telescope
that had suffered displacement, in all probability from
the fact that the tower on which the telescope rested
received more heat from the sun on one side that on
the other. This will give a hint of the minute accu-
racy requisite in astronomical observations. Further,
every instrument has its trifling defects, which import
an element of error into all observations, and is further
liable to disturbance by the most trivial occurrences,
so that to arrive at practically useful results there is
needed not only inexhaustible patience and persistence,
but also acute insight, so as to discover the various
sources of error and either devise a telescope that will
make them inoperative, or correct the results mathe-
matically. After the practical work of observation the
astronomer must be prepared for weary hours at his
desk. Every star must be observed several times, for no
one observation ever corresponds precisely with another:
and to the list of figures thus obtained, the Calculus
of Probabilities must be applied so as to arrive at the
closest possible approximation to the truth.
No one could appreciate better than Bessel the diffi-
culty of compiling such a catalogue, for he himself
stood in the first rank of observers, and had reduced
to workable form Bradley 's essay in the same direction,
which contained only single observations.
"Nearly all the Flamsteed stars", he writes, "were observ-
ed five times, so that I had to reduce to shape a total of
more than 25000 observations. ... On Piazzi's catalogue
GIUSEPPE PIAZZI. 77
which contains still more observations than Bradley's two
astronomers were engaged and the task occupied many
years: I am now convinced that that gigantic work has been
estimated rather below than above its value." I
Bessel drew a rich yield from the works of Piazzi
and Bradley. When he had resolved on his plan for
the revision of Bradley's catalogue he wrote to Olbers :
"Thanks to the known dexterity of Bradley, and the
excellent instruments of the Greenwich Observatory, Bradley's
catalogue yields little in point of accuracy to Piazzi's. An
interesting feat, surely, to attain the same accuracy in 1750
as in 1800!" 2
The collation and revision of the two catalogues
helped, in the event, to bring to light a very interesting
fact: the self-movement of the fixed stars. It showed
''that nearly one half of the stars contained in both
catalogues (numbering 2959) possess a self-movement
amounting to the tenth of a second annually, or, in
certain cases to more" 3 . The greatest movement was
that exhibited by a star of the fifth magnitude Nr. 61
of the Swan : it was as considerable as five seconds a
year. Bessel selected this double star on which to renew
the search for the long-sought parallax. His labours
were successful. He determined the parallax, about the
third of a second, and with it the distance of one of
the nearest fixed stars. "Nearest" is, however, hardly
a word to accentuate in this connection. Its distance
from the sun is according to Bessel about 657,700 times
the radius of the earth's orbit. Light takes ten years
1 Bessel an Olbers, 26 th February 1809 : Briefwechsel, herausgegeben
von Erin an, I 205.
2 io th May 1807: ib. I 9798.
3 Bessel, Populare Vorlesungen 248.
78 III. ASTRONOMY.
to travel that distance: a train covering 200 miles a
day would take two hundred million years 1 .
These discoveries count, it is true, to the credit of
Bessel, not of Piazzi, but it is clear that but for Piazzi's
work they could never have been made. Bessel him-
self speaks elsewhere of the "invaluable services" 2 of
the Italian astronomer, and always mentions his name
with the most marked respect. And a greater than
Bessel, Gauss himself, honoured Piazzi so far as to call
him his first-born son Joseph 3 .
It was his practice of observing each star more than
once that led up to the significant discovery of the first
asteroid, Ceres. On January I st he noted down the
position of a small star, on January 2 nd he made a
second observation of it but found figures different from
the first. Either then, one of the observations was in-
correct, or the star possessed a movement of its own.
Further investigation decided in favour of the latter
Piazzi was a member of the Order of Theatines
founded by St. Cajetan of Thiene. Born in 1746 at
Veltlin, he made his first studies at Milan and there
entered the Order. He received a decisive impulse
towards the cultivation of science from the two editors
and expounders of Newton, Thomas Leseur* (f 1770),
1 Bessel, Vorlesungen 261. 2 Ib. 239.
3 Cf. his Briefwechsel mit Bolyai 184.
4 Philosophiae naturalis principia mathematica ; auctore Isaaco
N e w t o n o , Eq. Aurato ; Perpetuis Commentariis illustrata, communi
studio PP. Thomae Le Seur et Francisci Jacquier, ex Gal-
licana Minimorum Familia, Matheseos Professorum. 4 vols. Genevae
1 739 J 74 2 - It was due in a great measure to this essay that New-
ton's work, the style of which was very involved, became generally
BARNABAS ORIANI. 79
Professor at the Sapienza, and Francis Jacquier (f 1788),
Professor at the Roman College, both of whom belonged
to the Order of the Minims of St. Francis of Paula.
Having completed his course in Philosophy at Genoa
and Ravenna, and in Mathematics at Malta, he was
appointed Professor of Dogmatic Theology at Rome
where he formed a lifelong friendship with his colleague
Barnabas Chiaramonti, afterwards Pope Pius VII. On
the advice of Jacquier, Piazzi in 1780 accepted the
post of Mathematical Professor at Palermo, and thus
made his entry into the field in which he was to attain
such distinction. He at once bestirred himself to give
the scientific Faculty an impulse in a new direction.
He was supported by the Government in his efforts,
and especially in his project of erecting at Palermo
an Observatory of the first class. Journeys to France
and England brought him into association with the
first scientists of the i8 th century, and gave him an
opportunity of appreciating the scientific needs of the
day. After his return the Observatory was erected in
1786, and Piazzi entered into occupation of it. Under
the rule of the Bourbons he received a call to Naples
where he died in I826 1 .
The "Columbus of the lesser planets" is not the only
Catholic priest who during the 1 9 th century rendered
notable service to astronomical science. We enumerate
here, in accordance with our general plan, the names
of the more notable.
One of the foremost, a co-discoverer of the new planet,
was Count Barnabas Oriani(fi832), Director of the Milan
intelligible , and that Newton's teaching gained ground. R. W o 1 f,
Gesch. der Astronomic 439 470.
1 For Piazzi cf. Cosmos 2 mars and 15 juin 1901, 269 f 748 f.
80 HI. ASTRONOMY.
Observatory, like Piazzi a priest and a successful astronomer.
Born of a poor family he began life as a mason : his edu-
cation was taken in hands first by some Carthusians who
recognised his great ability, and later by the Barnabites. His
work won him the rank of Count, and his reputation stood
so high that under Napoleon I. he might have become a
Bishop or Minister of Education if he had not declined
both dignities l .
Another name of European note is that of Giovanni
Inghirami (f 1851). Born in 1779 at Volterra, he entered
the Piarists at an early age. He studied Mathematics and
Philosophy in his native town, and afterwards Mathematics
and Astronomy at Florence, where he became Director of
the Observatory founded by the Jesuit L. Ximenez (f 1786).
He published in 1830, as the result of fourteen years trigono-
metrical mensuration, a map of Tuscany. When the Academy
of Berlin undertook the preparation of the chart of the
celestial equator, which was to contain all stars down to
the ninth magnitude, a section of this work was entrusted
to Inghirami. Although this section, that of the aggregate
nebulous stars, presented great difficulties, Encke, in his
speech at the celebration of the King's birthday in 1850,
characterised Inghirami's performance as amongst the most
remarkable in the whole enterprise. Equally high was the
estimate of Inghirami formed by Murchison, the well-known
geologist. Murchison praises in particular "the excellent map
of Tuscany which I found of great service in the geological
exploration of the Apennines" 2 . Inghirami attained in his
Order the positions of Provincial and General. He lies
buried in a chapel erected by him for the younger students,
and the inscription on the tomb asks them to pray for him
to the Blessed Virgin 3 .
1 Nouv. Biographic generate par Hoefer XXXVIII 786.
2 Journal of the R. Geographical Society of London XXII, London
3 A. v. Reumont, Beitrage zur italienischen Geschichte VI,
Berlin 1857, 472 478. An tone Hi, Sulla vita e sulle opere di
Giov. Inghirami, Firenze 1854. Allgemeine Zeitung, Augsburg 1851,
INGHIRAMI. CECCHI. SERPIERI. DENZA. 8l
Filippo Cecchi (f May 2 nd 1887), who came next but
one after Inghirami at Florence, belonged also to the Piarist
Order l . He specialised chiefly in Meteorology, and enjoyed
a great reputation in that department. The Meteorological
Observatory at Urbino was established in 1850 by the Prior
of the Piarist College there, Alessandro Serpieri (f 1885).
His researches were directed mainly to the storms of Italy,
shooting-stars and above all to the zodiacal light which he
sought to exhibit as a terrestrial phenomenon. He was
awarded a gold medal in recognition of his works on seismic
disturbances ; and on the suppression of the Orders he recei-
ved special permission to select a Chair in whatever Italian
University he liked best 2 .
Francesco Denza (f 1894) was a Barnabite. At the Con-
gress of Meteorologists held at Paris in 1878 he was elect-
ed President : for he had won a leading place in the science
not only by a series of valuable observations of his own,
but by his success in establishing all over Italy, "by private
persuasion, and by extensive correspondence" a network of
more than 200 meteorological stations. In addition to this
he made many contributions to the photography of the
heavens. The Vatican Observatory was rebuilt by him for
this purpose, and had the honour of being included among
the eighteen observatories to which was entrusted the pre-
paration of an international photographic chart of the
heavens 3 .
Nr. 246, p. 3929. Zach writes on 21 August 1830: "Mr. Inghirami
est un homme extremement actif." His Observatory is in better order
than the one in Florence in which Pons worked. Vierteljahrsschrift
der naturforschenden Gesellschaft in Zurich XXXI (1886) 237.
1 Civilta cattolica, Ser. 13, VI, Roma 1887, 484 485. T. Mar-
tini, Intorno alia vita ed ai lavori di Filippo Cecchi, delle scuole
pie, Venezia 1888.
2 Fed. M i c i , Al. Serpieri , scienziato ed educatore. Discorso
letto nell' inaugurazione dell' anno scolastico 1885 1886 nell' uni-
versita d' Urbino, Urbino 1 886.
3 J. Pl(assmann) in Jahresbericht der Gorres-Gesellschaft fiir
das Jahr 1894, Koln 1895, 2O 22 - Civilta cattolica, Ser. 16, I,
Kneller, Christianity. 6
82 III. ASTRONOMY.
The Jesuit Francesco de Vico, Director of the Observa-
tory of the Roman College, won a European reputation by
his laborious observations of Saturn and the comets. Driven
from Rome by the Revolution of 1848 he had an honourable
reception in France and England, but died suddenly at
London on October i5 th 1848 l . The Observatory of the
Roman College showed energies in other directions too,
so long as it remained in the hands of the Order 2 . At
the Jesuit's English College at Stonyhurst worked Joseph
Perry a "distinguished astronomer" universally known by his
publications on solar physics and earth -magnetism. . . . The
best proof of his ability is to be found in trie numerous
scientific commissions with which he was entrusted by the
English Government 3 . Thus he was sent to make obser-
vations of the Transits of Venus in 1874 and in 1882 in
the island of Kerguelen and in Madagascar respectively,
and in 1886, 1887, and 1889 to the West Indies, Russia,
and an island near Cayenne to study eclipses of the sun.
The last expedition (in 1889) cost him his life.
Great scientific activity was shown also by the "historic"
Observatory of the Benedictines at Kremsmiinster. Marian
Roma 1895, 93 94- Annuaire pour 1'an 1890 public par le Bureau
des longitudes 696.
1 A. S e c c h i , Ragguaglio intorno alia vita ed ai lavori del
P. F. de Vico , Roma 1850. Ami de la religion CXL, Paris 1849,
239 242. Ib. Civilta cattolica, Ser. I, VI, Roma 1851, 493.
2 Among the active members were C. Dumouchel (f 1840)
who was the first to rediscover the Halley Comet, which had re-
turned, and P. Rosa (f 1874), who in 1881 instituted observations
of the sun, comets, eclipses, and the passage of Mercury. When
Doppler in Vienna had drawn attention to the colour-phenomena of
the double-stars, B. Sestini (f 1890), who was soon afterwards
driven to America by the Revolution, taking up the study of these
phenomena, devoted himself to it for several years (Sitzungsberichte
der Wiener Akademie VIII  91).
3 Wildermann in Jahrbuch der Naturwissenschaften VI , Frei-
burg 1891 , 498. The particulars in The Month LXVIII, London
1890, 305 323 474488.
DE VICO. PERRY. ROLLER. RESLHUBER. FELLOCKER. 83
Roller (f 1866), Director of this Observatory, celebrated
for "his genius of observation" and his "perfect mastery of
the Calculus" published between 1830 and 1847 numerous
accounts of investigations made in Astronomy, Meteorology,
and Earth-Magnetism. "A worker of rare assiduity" was
the characterization of his successor Augustin Reslhuber
(f 1875). He was the author of many essays and treatises
on Meteorology, Terrestrial Physics, and observations of
comets , asteroids , etc. l Sigmund Fellocker was a
collaborator in the . Berlin Chart of the celestial equator,
completing in 1848 the portion (Hora VII.) assigned to
him 2 .
Mention should also be made of Canon A. Stark of
Augsburg (f 1839) whose observations of sun-spots were of
great value to R. Wolfe in his determination of the well-
known eleven years period: of the Jesuit Francis Paula
von Triesnecker (f 1817) remarkable for his extreme
industry in astronomical calculations 3 : and of the Bene-
dictine Placidus (Joseph) Heinrich (f 1825) of St. Em-
meram, whose contributions to the climatology of the Danube
Valley are "of the highest value" 4 . Halma (f 1828) and
Bossut (f 1814), two secular priests, published volumes on
the History of Astronomy 5 .
1 Allgemeine deutsche Biographic XVI 478 f; XXVIII 247 f.
S. Fellocker, Geschichte der Sternwarte Kremsmiinster, Linz 1864.
A. Reslhuber, Uber das magnetische Observatorium zu Krems-
miinster, Wien 1854. For Roller cf. Almanach der k. Akademie der
Wissenschaften XVII, Wien 1867, 201 239. Vierteljahrsschrift der
deutschen astronomischen Gesellschaft II, Leipzig 1867, 149 153.
2 C. Bruhns, Joh. Franz Encke, sein Leben und Wirken, Leipzig
3 Giinther in Allgemeine deutsche Biographic XXXV 488.
4 Giinther ib. XXXII 52. F. v. Schmoger, Erinnerungen
an PI. Heinrich , Regensburg 1825. Katholische Literaturzeitung
von v. Kerz 1825, II Intelligenzblatt 75; Verzeichnis der Schriften
5 Cf. for those named above R. Wolf, Geschichte der Astro-
84 JIT. ASTRONOMY.
The name of P. Angelo Secchi (f 1878) is so well-
known and so fresh in the general memory that it is
unnecessary for us to deal with him here at any length.
Even the Piedmontese Government did not venture, after
the seizure of Rome in 1870, to remove the world-
renowned astronomer from his Observatory, although
he resisted all inducements to betray his fidelity to Pope
Pius IX. and the Society of Jesus. Secchi's chief work
was done in the province of meteorology, his special
achievement being an apparatus for the automatic re-
gistration of meteorological phenomena. In speculative
physics too, he held a high position. His ideas on the
subject are to be found in his work on the "Unity of
the Forces of Nature". But nowhere does he appear
as the pioneer of so many new tendencies as in his
works on the physical constitution of the sun and stars.
He applied the methods of spectral analysis as created
by Bunsen and Kirchhoff to the investigation of the
stellar light, und in this way studied some 6000 fixed
stars. To this must be added his observations of spots
and protuberances on the sun, and exact measurements
of 1324 double stars. His papers on this subject are
so numerous that, as Respighi says, they seem "to re-
present the labours of a scientific association rather than
of a single individual". Moigno is of opinion that Secchi
single-handed did more work of this kind than the ten
collaborators of Arago. The catalogue of his writings
enumerates in addition to 65 separately published books
and papers, 42 reviews which contain contributions of
his, and in many cases very frequent contributions. Thus,
for instance, we find in the index of the Reports of the
Paris Academy of Science 182 papers and notes by
Secchi, in the Astronomical News of Schumacher 132,
ANGELO SECCHI. 85
in the Transactions of the Roman Academy de' Nuovi
Lincei 81, in those of the Italian Spectroscopists' Asso-
ciation 46, and so on 1 .
One can thus stand at the head of modern astronomy
without necessarily being an adherent of materialism and
atheism. This was the thesis which we wished to es-
tablish as against the assertions of certain writers, and
we think that the names to which we have made appeal
justify our contention. Piazzi and Secchi at least will
be conceded places in the first rank of astronomers,
and they were not merely believers in God but Catholic
priests. But let us inquire into this subject a little
further, and see whether among lay or Protestant leaders
of Astronomy the representations of our adversaries
find any better verification.
According to Madler, it is admitted on all hands that
Bessel and Gauss stand pre-eminent among the re-organi-
sers of Astronomy. They differed indeed in the nature
of their contributions, for "Gauss's activity, fruitful in the
highest degree, was confined almost exclusively to the
theoretical side , while Bessel , on the contrary leaves
us in doubt whether to admire most the number and
excellence of his theoretical works or the acuteness of
his observations, and the vast fields over which they
are scattered" 2 . With Gauss we have already dealt in
1 Cf. Jos. Pohle, P. Angelo Secchi. Ein Lebens- und Kultur-
bild, Koln 1883. C. Bricarelli S. J., A. Secchi in Memorie della
Pont. Accademia dei Nuovi Lincei IV, Roma 1888. C. Sommer-
vogel mentions other biographies and Secchi's own works: Biblio-
theque de la Compagnie de Jesus, i e partie: Bibliographic VII, Bruxelles-
Paris 1896, 993 1031. For the celebration of the 25 the Anniversary
of his death v. Civ. catt., Ser. 18, IX, Roma 1903, 614; X 349 and
the Works of B. Carrara (Padua 1903) and E. Millosevich (Rome 1903).
2 Cf. R. Wolf, Gesch. der Astronomic 525.
86 III. ASTRONOMY.
the section devoted to Mathematics, and we purpose
here to bring Bessel within the scope of our inquiry.
Born at Minden in 1784 Frederick William Bessel
had little opportunity of cultivating a taste for humanistic
studies. In mature life he set little store by them, and
held in all seriousness the opinion that no one could
be accounted an educated man who had not studied
Laplace's astronomical works. His father, an official
with a large family and mediocre resources, took him
away early from school, where indeed he had shown
no great promise, and apprenticed him to a merchant
at Bremen. Here Bessel had an exacting time of it;
his hours of business were from eight o'clock in the
morning till eight o'clock in the evening, but from the
first he was loyal and assiduous in his work. With the
design of qualifying himself to fill the position of "Car-
gador" or agent for over-sea trade he studied at night
Geography and Commerce, English and Spanish. He
determined to master also the Art of Navigation, as
likely to be very useful in his profession : this led him
into Astronomy, and Astronomy into Mathematics. The
field, into which he was thus introduced, took his mind
completely captive. From half past eight in the evening
till two o'clock he toiled at Mathematics and astronomical
calculations, but eight o'clock saw him once again in
In Bremen at that time lived Olbers, a physician and
celebrated astronomer, already known as the discoverer
of several of the smaller planets. One day the young
clerk plucked up courage to accost him in the street,
begging him to verify the computation of a comet.
Olbers consented, and recognising the rare ability of
Bessel, persuaded him to make Astronomy his profession,
BESSEL AND OLBERS. 87
and helped him to prosecute his studies. In 1810 Bessel
became Professor in Konigsberg, where an Observatory
was erected after his plans, and equipped with the most
perfect instruments of the day.
His relations with Olbers were always up to the
death of the latter of the most intimate kind ; Bessel
honoured him as a father. Numerous letters of both are
preserved J , a glance through which will be sufficient
to show the advocates of materialism that they can no
more rely on the authority of these two coryphaei, than
on that of Gauss.
It was assuredly no materialist who wrote the name
of God so often and so reverently as we find it in
"God be thanked, a thousand times over, that your wound
had no further evil consequences 1" he writes, when Bessel
had been bitten by a dog supposed to be mad 2 . "Most
gratefully must I celebrate the tender care of my good son. . . .
May God reward him for the love he shows towards his
old father." 3 "God keep you hale and happy!" 4 "Heaven
preserve you and yours in unclouded health and prosperity 1" 5
"Heaven grant you, my dear Bessel, health to follow on
to the end your great and brilliant discoveries!" 6 Similar
phrases are to be found many times repeated 7 especially
in the letter written by Olbers on August 14 th 1832. He
had just had a stroke of apoplexy and believed that he
was sending his friend a last farewell. "May Heaven bestow
on you, my dear, dear friend, many a long year of health,
strength, happiness and good fortune, so that your labours
1 Briefwechsel zwischen W. Olbers und F. W. Bessel, herausgeg.
2 Ib. II 76: 1 6. Februar 1818.
3 Ib. II 140: 20. April 1820. 4 Ib. II 198: 21. Mai 1821.
5 Ib. II 269: 25. Januar 1825. 6 Ib. II 280: 3. August 1825.
7 Cf. 'ib. I 257 383 399; II 228 252 285 296 435 438.
88 III. ASTRONOMY.
may develop still more fully a science which already owes
to you its complete re-organisation. God bless you and
yours 1 My hand trembles and my head grows heavy." ' . . .
Not long before his death he sent (July 5 th 1838) to
Bessel a letter in which he declares his belief in Provi-
dence and in the immortality of the soul. "He is, in-
deed", he writes, "troubled with the inevitable ailments
of old age."
"But all this has got to be borne, and no one can hope
for perfect health at such an advanced age. I am grateful
for the easy circumstances with which Providence has blessed
me, which permit me to spend my last years in otio cum digni-
tate. I am still able to rejoice in life. But in another
respect I am a conviva satur who has tasted and enjoyed
to satiety all of good that this earthly life has to offer and
is now able to take his departure without reluctance. And
this departure is made easier by the feeling that I am
become a wholly useless and dispensable member of human
society, and by my curiosity to learn in my own person the
experience which awaits man after bodily death. I pray