July 25, 1 872 J 



NATURE 



251 



Judging from the Report of the Exeter Science School in 

 connection witli the Cjovernment Department of Science and 

 Art, it seems altogether in a very satisfactory condition. There 

 are classes for Physical Geography, Matliematics, Acoustics, 

 Light and Heat, Chemistry, Animal and \'egetable Physiology, 

 Geology, Mineralogy, Metallurgj-, Botany, Building Construc- 

 tion, Theoretical Mechanics, Machine Construction, and Drawing. 

 From the number who have passed the examinations, it would 

 appear that the classes must have been well attended, and several 

 of the students have most creditably distinguished themselves. 



The following is a list of the electric lights in England and 

 France with the dates at which they were erected : — Dungeness, 

 Jan. 1S62 ; Cape La Heve, France, South Light, Dec. 1S63 ; 

 North Light, Nov. 1S66 ; Cape Grisnez, France, Feb. 1S69 ; 

 Souter Point, England, Jan. 1S71 ; South Foreland, 2 lights, 

 Jan. 1872. It is interesting to see that England took the lead 

 in this matter of the adaptation of electric illumination to light- 

 house purposes, and it must also be remembered that although 

 the first electric light was only erected in 1862, yet that in 1859 

 experiments were made under the supervision of the late Prof. 

 Faraday which were very successful. 



Mr. William F. Denning, of Bristol, writes us that the 

 sun's surface has recently been in a very disturbed condition. 

 On observing the sun on the afternoon of the 12th instant with 

 an old 4in. metallic-mirror rellecting telescope, he noticed a large 

 scattered group of spots in the north-eastern quadrant of the 

 disc. This group contained no less than t .venty-seven individual 

 spots, one of whicli was of considerable dimensions. It was 

 situated on the eastern portion of the group, and was constituted 

 of three well-defined umbrre and a large irregular penumbra, 

 whicli on the east side was very dark, and on the exleror edge 

 pierced with a train of minute dark spots. In the other quad- 

 rants Mr. Denning noticed four groups and one isolated spot 

 surrounded by penumbra in the north-western quadrant. These 

 groups (though insignificant in regard to the dimensions of the 

 spots which composed them) contained twenty-one spots in all ; so 

 that, including the large cluster before referred to, there were 

 forty-eight dark spots seen altogether. Several groups of faculse 

 were also perceptible in' the vicinity of the margin of the disc. 



TiiK first number of the Journal of the Society of Telcgmph 

 Eir^iiu-eis contains, besides a list of members, and the rules and 

 regulations, a record of the proceedings of the Society since its 

 formation, including reports of the papers read, and the dis- 

 cussions which followed. The members already number .about 

 280, and among them are the names of some of the most eminent 

 scientific men of the time, the President being Charles W. 

 Siemens, and the Vice-Presidents Lord Lindsay and Frank I. 

 Scudamore, C.B. The society " is established for the general 

 advancement of Electrical and Telegraphic Science, and more 

 praticubrly for facilit.iting the exchange of information and ideas 

 among its members," and consists of members, associates, 

 students, and honorary members. Besides the President's 

 address, in which he justly maintains that such a special society 

 "is necessary for the more rapid development of a new and im- 

 portant branch of applied science, " the report contains a paper 

 by Mr. R. S. Culley on Automatic Telegraphs, and a sketch of 

 the^Progress of Sea Telegraphy by Captain Colomb, R.N. The 

 latter half of the volume consists of "Abstracts and Extracts," 

 bearing on the department witli which the society is concerned. 



A NOVEL kind of magazine has made its unpretending appear- 

 ance — Loose Leaves, a magazine conducted at the Church Stretton 

 Private Asylum. It is written almost entirely by members of 

 the asylum, and we have seen many madder publications pro- 

 ceeding from those who consider themselves sane. As an eflort 

 to occupy the minds of the unfortunate inmates of such establish- 

 ments, the attempt is commendable, and worthy of_ all success 

 and imitation. 



HISTORICAL ECLIPSES 



TV/TR. J. R. HIND, writing from Mr. Bishop's Observatory, 

 Twickenham, to the i'inies, supplies the following interest- 

 ing sketch of the Eclipses recorded in History : — 



' ' It is well understood that the jiistorical eclipses, especially 

 those of the sun, have an important bearing upon our knowledge 

 of the elements of the moon's motion, as atibrding the means of 

 testing the accuracy of those elements when carried back to very 

 remote times. I send you a brief account of some results I luive 

 deduced in a systematic examination of these eclipses, making 

 only such a selection therefrom as may possibly possess interest 

 for the general reader. I phall omit any reference to the purely 

 astronomical conclusions to which I have been led, which would 

 be out of place in your columns, and, indeed, would extend this 

 communication beyond reasonable limits. It may, however, be 

 desirable to state that I have employed the last value of the secu- 

 lar acceleration of the moon's mean motion given by Prof. 

 Hansen, of Gotha, the author of the latest lunar tables, and have 

 combined other important elements as determined by him with 

 the results of M. Leverricr's tables of the sun. From recent in- 

 vestigations it appears by no means improbable that we may 

 have to rely wholly upon the ancient eclipses in fixing the true 

 amount of acceleration in the motion of our satellite. 



"IshallfoUowthechronologic.il order in the subjoined re- 

 marks upon some of the better known eclipses of history. These 

 form a part only of the phenomena I have rigorously examined 

 upon the same system of calculation. 



"I. The Nineveh Eclipse of B.C. 763, June 15. — The dis- 

 covery of the record of this eclipse on one of the Nineveh tablets 

 in the British Museum was announced by Sir Henry Rawlinson 

 in the Atheihntm of May 18, 1S67, to which I refer for details of 

 its bearing on the sacred and proiane history of the period. In 

 the actual state of our knowledge it is the tenninns 'a quo for re- 

 searches on the historical eclipses, and I believe I am correct in 

 saying its v.alue in an astronomical point of view is greater than 

 that attaching to the famous eclipse predicted by Thales to the 

 lonians, as mentioned by Herodotus. The underlining of the 

 inscription appears to indicate a phenomenon of unusual cha- 

 racter, or that the eclipse was total in or near Nineveh. Adopting 

 for the position of the city the longitude and latitude deduced by 

 the Astronomer Royal for the jiyramid of Nimrud, I find the 

 calculated southern limit of totality would pass a few miles south 

 of Nineveh, leaving a very large partial eclipse at that city. Very 

 trifling corrections in the lunar elements employed would suffice 

 to bring the total eclipse over it. In this longitude the duration 

 of totaliiy on the central line would be 4m. 20s., the middle of 

 the eclipse .at half-past 9 local time. 



"2. The Eclipse of n c. 6S9, January 11. — The idea that the 

 retrogression of the shadow on ' the dial of Ahaz ' during the 

 illness of Hezekiah may have been connected with a solar eclipse 

 has given rise to much discussion, and several writers have endea- 

 voured to point out how the occurrence might thus be explained. 

 Of the eclipses to which attention has been directed, the above 

 has perhaps appeared the more probable. It was an annular 

 eclipse, and at Jerusalem the sun would present the form of a 

 luminous ring for 7^- minutes, the middle at loh. iSm. In 

 Babylon it w-ould have the same appearance for seven minutes. 

 It seems hardly probable that the eclipse could have occurred 

 much later in the day, though more than one .author has con- 

 sidered the circumstance essential for the explanation of the 

 retrograde motion of the shadow on the ancient form of sun-dial 

 by an eclipse. I must leave the reader to judge how far the ex- 

 pression ' the wonder done in the land ' may relate to such a 

 phenomenon, which is, of course, a very rare one in a particular 

 locality. 



"3. The eclipse of Thales, B.C. 585, May 28. — This eclipse, 

 which, as Herodotus informs us, terminated the six years' war 

 between the Medes and Lydians under Cyaxares and Alyattes, 

 when during a battle 'day was suddenly turned into night,' has 

 greatly exercised the chronologist and the astronomer, and 

 alihough, misled by imperfect tables of the lunar motions, they 

 have fixed upon other eclipses from time to time, it has been 

 known for some years past that the date distinctly assigned by 

 Pliny (the fourth year of the 48th Olympiad) is the con-ect one. 

 My new calculation throws the shadow precisely over the tract 

 of country where with the greatest probability it has been sup- 

 posed the contending armies were situated, and in addition it 

 indicates a circumstance which I believe has not resulted from 

 any previous calculation, and which may not be without its 



