666 
NATURE 
| April 28, 1870 
What is the probable period of the ring?—The showers of 
1093-6 and 1122-3 at once suggest a period of from 26 to 30 
years. The nodal passage of the densest portion of the ring at 
the former epoch may be placed anywhere between 1093 and 
1096, and that of the latter, in either 1122 or 1123. The entire 
interval from B. C. 687 to A. D. 1803 is 2490 years, or 88 
periods of 28 y. 295 each ; and the known dates are all satisfied 
by the following scheme :— 
B.C. 687 to B.C. 15 672.000 yrs, =24 periods of 28.000 each. 
15 to A.D. 582 597.000 ,, =2I PY 28.429 ,, 
A.D 582 to 1093.714 511.714 ,, =18 ,, 28.429 ,, 
LOOSI7I4 CONS 2.149" O20;420 0555 = Ti ys 28.429 ,, 
1122.143 to 1803" 680;85 7,5) ==24 |) ye 28.369 ,, 
These coincidences indicate a period of about 28}* years, 
corresponding to an ellipse whose major axis is 18.59. Hence 
the distance of the aphelion is very nearly equal to the mean 
distance of Uranus. It will also be observed that the time of 
revolution, which seems to have been somewhat lengthened 
about the Christian era, was previously one-third of the period 
of Uranus. 
IT. The Meteors of December 11-13. 
In the catalogue of Quetelet we find the four following extraor- 
dinary displays which belong undoubtedly to this period. Obser- 
vations made in England, 1862, indicate also a more than 
ordinary number of meteors at the December epoch in that year. 
1. A.D. go1. ‘* The whole hemisphere was filled with those 
meteors called falling stars, the ninth of Dhu’lhajja (288th year 
of the Hegira) from midnight till morning, to the great surprise 
‘of the beholders, in Egypt.”—dodern part of the Universal 
flistory, 8vo. vol. 2, p. 81. Lond. 1780, The date of this 
phenomenon corresponds to the December epoch, A.D. gor. 
2. 930. ‘‘Averse remarquable d’étoiles filantes en Chine.” 
3. 1571. “On vit 4 Zurich ‘du feu tomber du ciel.’” 
4. 1830, 1833, and 1836. The maximum seems to have oc- 
curred in 1833, whenas many as ten meteors were seen simul- 
taneously. ‘‘ Dans la nuit du 14 au 12 décembre, on vit, 4 Parme 
une grande quantité d’étoiles filantes de différentes grandeurs, qui 
se dirigeaient presque toutesavec une grande vitesse vers le 
SSE. <A 10 heures et 4, entre les seules constellations du 
Bélier et du Taureau, on en compta environ une dizaine.”’ 
5. (Doubtful.) 1861, 1862, and 1863. Maximum probably 
in 1862. The meteors at this return were far from being com- 
arable in numbers with the ancient displays. The shower, 
ower: was distinctly observed. R. P. Grey, Esq., of 
Manchester, England, says the period for December 10-12 
was, in 1862, “exceedingly well defined.”+ 
These dates indicate a period of about 29% years. Thus :— 
GOL tOLQBON esse I period of 29.000 years. 
930 to 157I.........22 periods of 29.136 years. 
1571 to 1833 .. 9 periods of 29.111 years, 
1833 to 1862.......... 1 period of 29.000 years. 
III. The Meteors of October 15-21. 
The showers of the following years (see Quetelet’s Catalogue) 
belong to this epoch :— 
1. 288. ‘‘ Apparition en Chine.” 
2. 1436 and 1439. In each year a remarkable apparition was 
observed in China. 
3. 1743. (Quoted from Herrick, in Silliman’s Journal for 
April 1841.) ‘A clear night, great shooting of stars between 
9 and 10 o'clock, all shot from S.W. to N.E. [Qu. N.E. to 
S.W. ?] One like a comet in the meridian very large, and like 
fire, with a long broad train after it, which lasted several 
minutes ; after that was a train like a row of thick small stars 
for twenty minutes together, which dipt N.” 
4. 1798. ‘* Brandés marque, a Goettingue, un grand nombre 
d’étoiles filantes dans les observations simultanées qu’ il fait avec 
Benzenberg.” 
These dates indicate a period of about 274 years :— 
288 to 1439 ..... 42 periods of 27.405 years each. 
1439 to 1743...... II y 27.636 7 
1743 to 1708...... 2 7 27.500 Fel 
Tf these periods are correct, it is a remarkable coincidence 
that the aphelion distances of the meteoric rings of April 18th— 
2oth, October 15th—z21st, November 14th, and December 11th 
—13th, as well as those of the comets 1866 I, and 1867 I, are 
all nearly equal to the mean distance of Uranus, 
* Herri ssi vi 27 y 
April a eu a value of 27 years. 
t Silliman’s Journal for May, 1863, p. 461. 
See Silliman’s Journal for 
DIARY 
THURSDAY, Aprrit 28, 
Royat Society, at 8.30—On the organs of Vision in the Common Mole: 
Dr. R. J. Lee.—On an Aplanatic Searcher applied to Microscopes; Dr. 
Royston Pigott.—On a cause of error in Electroscopic Experiments : 
Sir Chas. Wheatstone, 
ZooLocicaL Society, at 8.30.—Notes on a North-American Batrachian 
(Spelerpes rubra); Mr. St. George Mivart.—Notes on some points in 
the anatomy of certain Kingfishers: Dr. Cunningham.—On a new 
gigantic Amphibian, allied to Lefidosiven from Queensland :—Mr. G. 
Krefft. 
Roya. InsTITuTION, at 3.—Electricity : Prof. Tyndall. 
FRIDAY, Aprit 29. 
Roya InstiTuTIoN, at 8.—Popular Myths: Prof. Blackie. 
ZGOLOGICAL SOCIETY, at 1.—Anniversary Meeting. 
SATURDAY, Apri 30. 
Roya. INsTiTuTION, at 3.-—Comets: Prof. Grant. 
MONDAY May 2. 
ENTOMOLOGICAL SocieETY, at 7. 
Society oF Arts, at 8.—Cantor Lecture on Fermentation: Prof. A, W. 
Williamson. 
Roya. ASIATIC, at 3. 
Roya InstiTuT10n, at 2.—Annual Meeting. 
TUESDAY, May 3. 
ANTHROPOLOGICAL SocrETy, at 8.—The Aboriginal Tribes of the Nilgiri 
Hills; Major Ross-King.—The Armenians of Southern India; Dr. 
John Shortt.—The Kajahs of Southern India: Dr. John Shortt. 
Roya INsTiTuTION, at 3.—Moral Philosophy :—Prof. Blackie. 
THURSDAY, May 5. 
Roya Society, at 8.30. 
Society oF ANTIQUARIES, at 8.30. 
Cuemicav Society, at 8.—Vapour Densities: J. T. Brown.—New Cornish 
Minerals, No. 7: Prof. Church. 
Royav InstiruTion, at 3.—Electricity: Prof. Tyndall. 
Linnean Society, at 8, 
BOOKS RECEIVED. 
Enctisu.—On Natural Selection: A. R. Wallace (Macmillan and Co.).— 
Sketches of Creation, illustrated by Prof. Winchell: (S. Low, Son, and Co.) 
—The Population of an Old Pear Tree, translated’from the French of E. Van 
Bruyssel (Macmillan and Co.).—Records of the Geological Survey of 
India. Vol. I., parts x, 2, 3; vol. II., part 1.—Contributions to Botany : 
J. Miers; vol. 2 (Williams and Norgate).—Symons’s Monthly Meteoro- 
logical Magazine ; vol. for 1869.—Trees and Shrubs for English Plantations : 
A. Mongredien (Murray). 
Foreicn (through Williams and Norgate).—Die Schule der Chimie: Dr. 
J. A. Stéckardt.—Der Elektromagnetische Telegraph: Dr. H. Schellen.— 
Le Darwinisme et les générations spontanées: D. C. Rossi.—Catalogus 
Musei Botanici_ Lugduno-Batavi: Prof. Miguel.—Verzeichniss von 4793 
teleskopischen Sternen: Dr. J. V. Lamont—Annalen der kéniglichen 
Sternwarte ; vol. 17.—Der rationelle Wiesenbau: L. Vincent.—Die fiinf 
Sinne des Menschen: W. Preyer.—Zeitschrift fiir die gesammten Natur- 
wissenchaften ; vols. 33, 34: Drs. Giebert und Siewert.—Handbuch der 
Mathematik: Physik, Geodasie und Astronomie: Dr. A. Wolf.— Die 
Erfindung des Fernrohrs und ihre Folgen fiir die Astronomie.— De la Reforme 
de l’enseignement supérieur et des libertés Universitaires: C. Schiitzen- 
berger.—Meémoires de la société royale des Sciences de Liége ; vols. 1, 2 
CONTENTS 
Wuat 1s Enercy? By Dr. Batrour Stewart,F.R.S. . . . . 
LEGISLATION AND NaTurE. By E.Goapsy ....... + 
Dr. JELINECK ON METEOROLOGICAL OBSERVATIONS. «. « « « 
OS hoya Aw Oo oldenes 8a bold "G0 5 5.0 5 ORD 
LETTERS TO THE EDITOR :— 
Analogy of Colour and Music.—JoszrH JoHn Murpnuy; J. G.; 
WS JOXKELY.. mal ste tA Cah De «) Seketnyy -<atenOBx 
The Barlow Lens.—F. p’A. . . . .. | : 653 
A Word in Defence of Physicists.—O. FisHEer - 654 
Heat Unitsie—Ga Ge HOSTER) HiRes.) ts) inlets taneren teint » 654 
“‘Dhée! Sun‘s|Ghromosphexejis. scsreren el) SP siece ma eee eee » 654 
Left-handedness POR CROL IT tre Rom Ge ordt a vc. on (a 
THE ABRADING AND TRANSPORTING PowER OF WaTER. II, 
FRICTION OF WATER (with diagram).—By T.Locin . . . . . 654 
THE ScieNcE OF EXPLOSIVES AS APPLIED TO WARLIKE PURPOSES. 
I, Earty Stupy AND APPLICATION OF ExpLosives. (Wik 
gliustyaiion) = ob) cence. sis) 4 eT ee Romi oo. 
Tue Deer-SEA SounpDINGS AND GEoLocy.—Pror. T. H. Huxtey, 
BARUSH ao mecilcs Gina: Aes ita cate Manuel autre care . 657 
INOTES?s 3) St. he) eyes) Ge ols Moelle n alcomeel (e)ntGrer eae ROSS 
MapREPORARIA OF THE RED SFA... . + 660 
On THE CHARACTER AND INFLUENCE OF THE ANGLO SAXON Con- 
QUEST OF ENGLAND, AS ILLUSTRATED PY ARCHAZOLOGICAL 
ResearcH. By Dr. GeorGE Roiueston F.R.S, . + 661 
SOCIETIES AND ACADEMIES. . - « « « « « « + + « « « « » 662 
IDI See GG old aMoem otc lao oO G 6 “Deal o ooo - 666 
Errata.—In No. 24, page 630, second column, line 10; for ‘‘ Acalephic ” 
read ‘ Acalephe.”—Page 635, column 1, line 5 from bottom, ior “‘ Von 
Martins,” read ‘‘ Von Martius ; and column 2, line 4: for ‘* Martins,” read 
“* Martius.” 
