Rodolfo Amedeo Lanciani.

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Want of space compels us to pass the interesting chapter on
" Personal ea nation in determining time," with simpFp^ the remark
that the orainary methods of measuring that e(}uation being
inapplicable, by reason of the distance ana other circumstances,

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GhulcPa Beport on Treens-Ailantic Zongiiude. 241

comparisons were made between the observers for this purpose
as soon as practicable after their return; and the values
deduced, though in many resjjects quite unsatisfactory, were
adopted as the best approximation that could be obtained for
the diflferent observera They are these :

Gould — Mosman =-^0»*02

Dean— Mosman =4- ^'1 1

Goodfellow — Dean =+ 0'14

Boutelle— Goodfellow =— 0-14

Boutelle— Chandler =- 0-04

A special wrangement, by which it was intended to entirely
eliminate personal equation at Heart's Content^ unfortunately
foiled through some misapprehension of the observers. The
fact, however, that they had been in the practice of observing
togedier for many years and had always found the equation
between them to vary between very narrow limits, on Ibe two
sides of zero, rendered the failure of little practice eonsequenoe.

We hasten to give briefly the final results for lon^tude.

Between Foilhonunerum and Heart's Content we have for the
several dates, aft^ corrections applied : —

1866, Oct. 26, 2* 51" 56»-467

28, -468

Not. 5, -466

6, -481

9, -460

The final longitude deduced, after correction for personal
equation in determining time, Dean — Mosman— +0*11, and in
noting signals. Dean — Gould =4-0" -03, becomes

1=2^ 61°» 56"-54

Between Heart's Cont^it and Calais, the results, similarly cor-
rected, are for the several dates : —

Dec. 11, 0^ 65» 87*-98

12, f37*63]

14, 87-84

16, 37-82

And the final result, corrected by — 0'-14 for personal equation
between Boutelle and Goodfellow, and omitting Dec. 12, is —

Between Greenwich and Poilhommerum, the longitude was
obtained by satis&ctory signals on two nights, and compared
with two previous determinations by Mr. Airy for other points
at Valencia, by short geodetic connectiona The two nights
exchanges gave
Am. Joitb. 8oi.— Sboohb Sbriis, V0L.XLIX, No. 146.— Maboh, 1870.

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242 GxmUds Beport on Ihuns-Atlantic Longitude.

1866, Nov. 6, O** 41" 33"-306 0«-115
13, 33-280 0-110

Mean, 41 33*29

This differs by — 0*10 from that adopted by Mr. Airy as
deduced from the great chronometric expedition of 1844, and
the tel^raphic determination of 1862.

The combination of the three longitudes thus determined,
gives —

Greenwich — Foilhommerum, 0** 41°^ 33'-29

Foilhommerum — Heart's Content, 2 61 66*64*
Heart's Content — Calais, 66 8 7 '72

Greenwich — Calais, 4 29 7*66

" The Valencia observations having been made by, or refer-
red to, Mr. Mosman throughout the whole period, his personal
equation is eliminated ; the equation between Messrs. Goodfel-
low and Dean, always small, may be regarded as trustworthy,
and by a happy coincidence the personal equations of Mr. Bou-
telle on the west, and of Mr. Mosman on the east, seem to be
almost identical, so that even a total disr^ard of this (quantity
would have resulted very nearly in its perfect elimination, the
oceanic arc being diminished and the land arc increased, eacli by
about 0*-14."

The only probable influence of personal equation in the
entire longitude-measurement, comprising, as it does, three-six-
teenths of the whole circumference, lies in the difference between
the observations of Messrs. Dunkm and Boutelle.

The longitude of Calais, as heretofore telegraphically deter-
mined, is as follows : —

Calais— Bangor, 0^ 6"» 0»-31

Bangor — Cambridge, 9 22-99

CanAridge — New York, 11 26*07

New York— Washington, 12 16*47

Calais — ^Washington, 39 4*84

whence we have

Greenwich — Washington, 6*^ 8" 12'*39

The Seaton Station being 12'*44, and the dome of the Capi-
tol 10"17, east of the Naval Observatory, to the center of tne
dome of which the preceding value refers, we have as their lon-
gitudes from Greenwich —

Seaton Station, 6^ 7°» 69»-96

Capitol, 6 8 2-22

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OouUCs BepoTt on Trans-Atlantic Longitude. 243

From the fects, as exhibited in this report, there woxild seem
to be every reason to believe that this result is within a very
small fraction of a second of the exact longitude, and that the
small probable error, whatever it may be, is mostly due to the
weakest link in the whole chain — that between Newfoundland
and Calais.

The indiscriminate mean of all the chronometer determina-
tions, as given early in this article, using the numbers of chro-
nometers as weights, is 5^ 8™ 12"'14 ; leaving out Bond's first
discussion of the 175, it is 6^ 8" 12"-37. The mean of Peirce's
two from occultations of Pleiades, without r^ard to weight, is
511 3m i2'»-29.

We r^ret that we have not room for even a brief abstract of
the valuable closing chapter on the transmission-time of signals,
but are compelled to dismiss it with barely stating the gene-
ral result and some conclusions with respect to a few points, as
derived from the exj)eriments.

The transmission-time by cable, after correction for personal
error in noting signals (0"'308), was found to be for the several
dates: —

1866, October 25, 0*-814 Cable of 1 866, with earth and condenser.
28, '343 " " ** " " "

November 6, '280 Both cables, no earth.
6, -248 " " " "
9, 0-240 " " " "

The battery-strength on these nights was as follows : —

October 25, 10 cells at Valencia, 10 cells at Newfoundland.
28, 10 " " " 10 " " "

November 5, 3 " " « 3 " ** «

6, 3 " " " 10 " " **

9, 4 ** " " 10 " " "

From these results the inferences seem warrantable, 1st, that
the velocity of transmission is greater when the circuit is direct
and consists of a good metamc conductor exclusively, than
when the signals are given by induction, although the earth may
be at the other electitxie ; and 2d, that an increase of intensity
in the electromotive force is attended by an increase in the ve-
locity of propagation of the signaL

From tne observations for longitude, and from other experi-
ments made with special reference to particular points, the fol-
lowing general conclusions were reached.

" It appears manifest that not an electrical charge or discharge,
but simply an electrical disturbance, is requisite for transmit-
ting a signal ; that an inductive impulse, sumcient to deflect the
galvanometers employed, was transmitted through one cable,

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244 H, A. Newton on ike Meteors o/Novmtbery 1869.

having at each end a condenser with 10 cells, in somewhat leas
than me third of a second, five seconds after the transmission of
an impulse of the opposite sort ; that with a circuit formed by
die two cables, a smaller dectiomotive force sufficed to trans-
mit the signals with yet greater rapidity ; that the signals trav-
eled more raj)idly through a cable whicn had not recovered its
electrical equilibrium after a current of the opposite character ;
imd that the speed of the signals is modified by the earth-con-
nections, more readily than oy changes in the battery-power.
And the very marked differences, found in Ae rates of trans-
mission, between sisals given by completing an interrupted
circuit and those given by interrupting a closed circuit, may
perhaps lead to investigations which will afford an explanation.

C. S. Lyman.

Art. XKYUL— Meteors of November^ 1869 ; compiled by H. A.


The cloudy weather in most parts of the United States and
Europe prevented continuous observations of the Nov^nber me-
teors, at the time of their return in 1869, by nearly aU those
who were watching for them. The observers, m the rew Nations
where the skies were clear, ftimish, however, ample testimony
to the appearance of unusual numbers on the morning of Nov.
14th. The display, moreover, like that of 1868, continued for
several hours. I give below the particulars of the observations
at various places.

1. At New Haven. — Two members of the Junior Class, Messrs.
C. B. Dudley and R P. Maynard, saw, through openings in the
clouds, six meteors, between 4^ and 6^ on Ihe morning of the
14th. Some of them had the peculiar trains belonging to the
November meteors. On the next morning, Nov. 15m, the sky
was nearh" overcast, but between 8* and 8^* 45™, we saw eight
meteors, lour of them conformable. During Ihe rest of me
morning the sky was overcast, and even in mis interval it was
at no time more Ihan one third dear.

2. A similar failure, nearly or quite complete, is reported by
Prof Eastman, at the U. S. Naval Observatory, Washington, by
Mr. Marsh and Mr. Taylor, at Philadelphia, oy Mr. Fuertes at
Stamford, Conn., by Mr. Boemer, at vevay, Ind., bv Prof
Eockwood at Brunswick, Ma, and by various others who were
in readiness to make observations.

8. At Pensacola, Fhridcu — To the courte^ of Commodore
Sands, Sup't of the TJ. S. Naval Observatory, we are indebted
for a letter of Commander Wm. Gibson, ftom Pensacola. He
says that the night of the 18th-14th was exceedingly bright and

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H A. Newtm on the Meteors of Novmher, 1869. 245

dear, and that the shootmg stars were observed in extraordinary
numbers, from 1^ 15™, A. M., until dawn, most numerously be-
tween 3^ and 4^ A. M. It was diffiexdt to give the average per
minuta It varied from two or three to twenty or thirty, or
more, the star-showers flashing and intermitting like the bursts
and pauses of a gusty rain. In magnitude they varied from
mere moving points of light, to those which were larger than
Jupiter. One train remained visible at least 50 minutes, drift-
ing slowly to the northward.

4 Upon the Pacific Ocean. — To the courtesy of the Secretary
of the Smithsonian Institution, we are indebted for a letter of
Mr. Alexander Evans of Elkton, Md.

On the morning of Nov. 14th, he was upon the Pacific
Ocean, lat 8^ 80' N., and long. 84° 80' W. He watched from
two till four o^clock, when the sky became overcast Between
these hours the sky was partly covered. The display was, he
says, quite eaual to that of 1868 which he observed throughout
He thought mat the radiant point was not as last vear, m the
center of the sickle in Leo, but a little more to the eastward
between the stars t, and y. There were several nonconformable
meteors whose radiant seemed to be the zenitL

5. At Santa Barbara^ CaltfomioL — ^To the courtesy of Pix>£
Peirce, Superintendent of the TJ. S. Coast Survey, we are in-
debted for the observations of Mr. Geo. Davidson, Assistant,
and Mrs. E. Davidson at the Coast Survey station, at Santa
Barbara (lat 84^ 24', Ion. 7»» 59°»). Between l** 18", a. m.,
and S*' 43™ on the morning of Nov. 14th, they counted 556
meteors. The following table represents the number of meteors
seen by the two observers per minute. They are taken from
the diagram forwarded by Pro£ Peirca

1^ 33B 2-2 meteors.
35 3-6 "
47 4-8 "
63 6-0 "
69 3-8 "

2 9 4-8 "

Jh \m 6-0 meteore-l


6-2 "


60 "


2-2 "


2-2 '•


6-6 "

2b 46m 3.0 meteors.!







3 1









3h 16m 50 meteora
21 2-6 "
26 2-0 "
31 3-7 "
36 3-2 "
41 4-0 "

Mr. Davidson says, " the night was beautifully clear, the
moon being ten days old, and 4° soutk I was called at l** 10"»,
A. M., up to which time 22 meteors had been seen. After
S*" 43", A. M., watch was kept for any unusual display, but the
numbers gradually diminished. Some of the meteors were
very brilliant and left persistent trains. About half a dozen
meteors were observed moving in directions toward the radiant

"At 2*> 33«, A. M., I observed a brilliant meteor start fix)m a
point above, and a little to the left of the pointers ; it left a
persistent train and disappeared at a point about 9° or 10®
above Polaris, and 6° to the right The train was 5° in length ;

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246 H. A. Newton on the Meteors of November^ 1869.

gradually it took a wavy form ; then curved until it formed
two-thirds of an irregular circle, and was 3° in diameter and
half a degree in widtL I examined it with a good binocular,
and found it not of uniform density, but having open spaces in it.
It remained visible 8^ minutes, and in that time apparently
moved in a line toward the radiant point in Leo, over a space
of 8°."

The small number of meteors reported above as seen
between 2*» 80" and 2*» 40" was due to Mr. Davidson's being
engaged in watching the train of this meteor.

At V^ 16" Mr. S. R Thockmorton, Jr., saw a meteor appear
and disappear without apparent motion. It was about two
degrees alx)ve and to the left of the bright star in the blade of
the sickle.

6. At Fredericton, K 51, (lat 46'' 8', Ion. 66' 45').— A watch
was kept up by relays of students of the University of New
Brunswick, throughout the night of Nov. 18th, 14th. They
report the times and general directions of the individual
meteors, with duration of flight, brilliancy, &c. The following
table of the numbers seen in each 10 minutes of the night is
compiled from their report


f meteors

night of Nov. 13^. I4t^.








1— 8





8— 9




























12— 1








1— 2








2— 3








3— 4








4— 6








5— tt








6— 7





Total in

11 hour



The observations were made by three parties, each watching
for two successive hours. Messrs. Byers, Crozier, Stone, Con-
nell and Williston watched from 7i** to 9^ and from 1^ to 3^.

A second party, consisting of Messrs. Vanwarts, Cliif, Wort-
man, Belyea, and Lawrence, watched from 9** to 11** and from
8^ to 5^ , and a third party consisting of Messrs. Willbur, Sco-
vil, Chandler and Walker watched from 11^ to 1^ and fix^m 6^
to 6^^. Only four persons were, however, observing at any
one time.

7. In Bngland, — ^The clouds prevented observations for most
of the time in Great Britain. At Glasgow, Mr. A. S. Herschel

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H. A, Newton on ike Meteors of November^ 1869. 247

and Mr. Robert McClure had a tolerably clear sky fix)m half
past 4 till half past 6.

" Meteors of tne brightest class of the November shower, hav-
ing luminous streaks, were crossing the sky at the rate of about
40 in an hour, for one observer, corresponding to a rate of fre-
quency of at least one hundred per hour, in all the sky. The
apparent paths of thirty of these meteors were recordea upon a
map, by tneir course among the stars, and the direction of their
flignt was from the usual radiant point in the constellation
liCO. * * * *

" A clear view of the sky was again obtained towards eleven
o'clock on Sunday night, when a single shooting star, passing
from Gemini to Taurus, and leaving a faint streak, appeared to
be the last visible representative of the November meteora Al-
though the sky continued clear, and an attentive watch was kept
for nearly three hours afterwards, no other meteor could be seen.
The purely negative character of this result adds a fresh proof
to the evidence obtained in former years of the definite bounda-
ries and narrow limits between which the stream of the Novem-
ber meteors is confined."

Observations at Greenwich and at most other places in Eng-
land were not successful on the morning of the l4th.

At OuHoden, Mr. A. Forbes counted upwards of 200 between
the hours of 8** and 7^^ a. m., the maximum of the shower
appearing to be about 5 o'clock.

8. In rVance^ the ** Association Scientifique" organized a sys-
tem of observations, at various stations near the Mediterranean,
embracing even one or two in Italy. The results were to be re-
ported and discussed at sessions to be held in the latter part of
the month of November, at Marseilles and Bordeaux. We have
not learned what success rewarded the zeal of the French ob-

9. At Paris. — Mr. Chapelas reports to the French Academy
of Sciences, that notwithstandmg unfavorable weather and
moonlight, " observations conscientiouslj^ made, give us for the
mean hourly number reduced to midnight and to clear sky,
and corrected for the influence of the moon, for the night of
Nov. 12th, 6-8 meteors; for the night of Nov. 18th, 24-8

He says that the observations for the preceding nights gave
steadily, a smaller hourly number than the mean for that period
of the year, which is, according to him, 18 '6.

Mr. Chapelas, as usual, does not say how many meteors he
saw, nor how long he observed, nor how large a correction he
applies for cloudiness, nor what for moonlight, nor what to
reauce to midnight We are not aware, even that he has pub-
lished rules or constants for such reduction. His observations
might perhaps have some value, if we knew what they were.

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248 R A. Newton on the Meteors of November, 1869.

They could then be criticized, and compared with those of
other observers. K found to have been carefully made thev
would be valuable to scienca But as now given to the worla,
the observations of Mr. Coulvier-Gravier and Mr. Chapelas are
inextricably mixed up with their deductions. The manifest
errors of the latter taint the whole, and make it necessary to
throw them all away. The French Academy of Sciences pub-
lishes his reports, and we respectfully call its attention to the

10. At Vienna. — ^Prof Weiss of the Observatory of Vienna,
with three aids, determined 36 paths with the meteorosoope
between 2^ and 6\ A. M., of the 13th (Prof Schmidt in ^eis
WochenschriA Dea 8th). Some of them were from the Leo
radiant The total number visible was verv moderate.

The next night was stormy, and for an interval of 10 minutes
only at 4**, A. M., could anything be seen. A few stars of Leo,
Gemini and Auriga were then visible through openings in the
clouds, and along with them, though principally seen through
haze, were some meteor tracks, havmg trains and radiating
from Leo. Prof Schmidt estimated that the hourly number
for one observer was about 50, reckoning only the brighter
meteors, and considered the display not greatly different from
that seen by him at Athens in 1863.

At Munster and elsewhere in northern Germany the sky
appeai-s to have been overcast

11. At Rome, — ^The cloudy skies which covered northern
Europe on the night of the 13th, 14th, also impaired the
Italian observations. Padre Secchi reports a few, though
incomplete, from Rome.

At 2*> 30*" A. M. the clouds broke away in the west and in
five minutes 18 meteors were seen. At 2^ 35" the sky was
nearly clear except low in the northeast, and a regular count
was begun.

From 2»» 35" to 2^ 40", 29 meteors were seen ; from 2** 40'»
2h 48", 41; from 2^ 48°»to S** 0°», 73; from 3** 0»to 3** 15°^ 40.
At 3^ 18™ it became again overcast The whole number in 40
minutes was 183, of which 5 were unconformable He omits
to state the number of observers. Padre Secchi concludes :

1st That there was a real recurrence of the display.

2d. That it was but little different from the display last year,
there having been then seen in the same interval about 200
meterors. The hour moreover was not that of the maximum.

3d. That the radiant point was within the bend of the sickle
in Leo, and made with the stars « and f* an equilateral triangle.
But this determination was not very precise owing to the want
of tracks near the radiant

4th. That the greater part of the meteors passed to the north
of the radiant

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H. A, Newton on the Meteors of November, 1869. 249

It was farther remarked that the trains were visible only a
few seconds, and that there were none of the beautiful scrolls
of smoke which were seen last year.

Madame Scarpellini gives in her Corrispondenza Scientifica
accounts of observations at Rome by herself, (with negative
results) and the following from Perugia and Civita Vecchia.

12. At Oivita Vecchia. — ^Prof. Pinelli reports to Madame Scar-
pellini the following observations from Civita Vecchia.

Nov. 12th-18th. Between lO*" 30™, p. m., and l^ a. m., 4
meteors seen of 1st magn., 6 of 2d magn., and 8 of the third.
Only a few clouda

Nov. 18th-14th. Between 11** 80™ and 2'' 85™, 54 meteors seen.
Very cloudy and finally overcast.

Nov. 14th-15th. Up to 1^ 20"», A. M., only 16 meteors seen.

13. At Perugia.— On the morning of the 18th from 12*' to 6S
A. M., Prof Bellucci counted the following numbers in the several
hours; viz., 26, 22, 26, 28, 24, and 17. In all 138 in six hours.

On the next night in successive hours from 6^, P. M., till 4'*,
A M., he saw 8, 1, 0, 2, 1, 2, 0, 39, 190, 246. During the next
half hour 71 were seen, making 555 in alL From 4^ 80™ it
was overcast

14. At Velletn. — Prof D. Ignazio GaUi, of the Municipal Ob-
servatory at Velletri, watched during the two nights of the
12th and 14th of November. (Bull Met. Rom.\

On the first night, two observers, With a clear sky, in five
hours, from 12*^45" till 5^45", saw 71 meteors. The distribu-
tion through the five hours was as follows :

From 12" 45"

to 1" 46"

2 conf ,

9 xinconf

" 1" 46'°,

" 2" 45",

5 "

7 "

" 2" 45",

" 8" 46"

8 "

6 "

" 8" 45°",

" 4" 45",

7 "

7 "

a 4h 45«^

" 5" 45"

11 "

9 "

On the second night they were able to see only through
openings in the clouds. There were three or four observers,
enough to ftiUy command the whole of the visible portions of
the sky. The results were as follows :

Meteors seen.

Portion of

Total computed


Conf. Unconf.

akr Tisible.


1* 0" 1" 15-

50 1



1 15 1 80

48 1



2 2 16

41 6



2 15 2 80

81 7



2 SO 2 46

48 4



2 45 8

62 8



3 8 15

17 4



Total in 1" 46",

292 81

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250 H, A, Newton on the Meteors of November^ 1869.

The meteors of this second morning were much finer than
those of the preceding morning. The sporadic meteors of each
night appeared to radiate from AurigL

15. From Moncalieri — ^Director F. Denza reports in Les
MondeSj for four observers :

Night of the 12th of Nov. from ]4»» to


145 meteors.

" 13th " 9


720 "

» 14th " 14l»10m

17b lOm

99 "

These numbers need to be increased, as their nrincipal object
was to determine the position of the tracks ana the instant of
appearance of the meteors.

On the night of the 13th, 14th, there were seen :

At Alexandria bj 4 observers from 9b 45°^ to 16^ 46™, 168 meteors,
AtAosta, 1 " 14b 30in igh 189 "

AtVaraUo, 1 " 13«» 25™ 16^ 26™ 121 "

Prof Denza adds that " the meteoric shower of Nov. 1869,
differs little from that of August, and in some places was even
inferior to it"

16. At Port Said, Egypt — ^In the Monthly Notices for Dea are
some observations of Gr. L. Tupman, Esq., at that place. On
the mornings previous to that of the 13th, he detected some
tendency to radiation from Leo. On that morning, of thirteen
meteors, four were conformable.

On the morning of the 14th from 12*^ 80°» to IS"* 15"» only
two meteors were seen, neither conformabla There was a
pretty large patch of clear sky overhead.

" The watch was resumed at 14^ 80", the sky being then
partly clear in patches, and continued until a quarter past 5,
long before which the shower had entirely ceased. At 2** 80"
it was at its height, most of the meteors being remarkably bril-
liant, and many of them tinted green. The greater part left
bright streaks, which often remained visible a considerable
time. The duration of the meteors or their 'time of flight'
was considered to be less than half a second — ^too short a time
to estimate even roughly.

"The following are the observations Being unassisted, I
stopped at e\ ery sixteenth to make the necessary entries.

"if the numbers in the table be reduced to an uniform

Online LibraryRodolfo Amedeo LancianiThe American journal of science and arts → online text (page 29 of 109)