NA TURE 



[Fed. 19, i< 



Shocks of earthquake continue to be felt in the south of 

 Spain. A telegram from Granada on the 12th stated that slight 

 shocks continued to be felt at Alhama, and on that day there 

 was a shock at Terre del Campo near Jaen. There were also 

 shocks in the evening of the 14th at Granada and Velez 

 Malaga. 



DieNalnr takes advantage of the attention at present directed 

 to South Africa, to recall the story of the first astronomical ex- 

 pedition to the Cape. The first expedition ever sent across the 

 seas for such a purpose as astronomical observation was that of 

 Jean Richer, which went to Cayenne on behalf of the Paris 

 Academy, in order that simultaneous observations of Mars should 

 be made there and in Paris. The Cape expedition took place 

 thirty years later. Baron Krosigk, its promoter, had founded a 

 private observatory at Berlin, where observations of the moon's 

 culminations were made for a long period, and observers were 

 sent to the Cape to make corresponding observations there. It 

 was hoped that by collating the observations in both places the 

 moon's parallax would be obtained. So far as this was con- 

 cerned, the expedition failed. Wagner, the founder and first 

 head of the public observatory at Berlin, carried out his part of 

 the work in Prussia, but Kolb, who had charge of the Cape 

 expedition, was guilty of great negligence, so that the results 

 were inconsistent and unsatisfactory. In 1 7 19 he published a 

 book entitled "Caput bona; spei hodiernum," in which he 

 described everything at the Cape except what he was sent to do. 

 The work which Krosigk hoped to do then was not completed 

 for another forty years, when Lacaille and Lalande made the 

 necessary observations, the one at the Cape, the other in Paris. 



Mr. Carl Armbruster will begin a course of five lectures 

 at the Royal Institution on " The Life, Theory, and Works of 

 Richard Wagner," on Saturday, February 2S (with vocal and 

 instrumental illustrations). 



In order to ascertain the truth of the assertions recently made 

 by certain ichthyologists in regard to the capacity of Canadian 

 salmon to exist in sea water, an experiment has been made in 

 the South Kensington Aquarium, several specimens being de- 

 posited in one of the salt-water tanks, where they lived for eight 

 days, when they expired in rapid succession. This entirely dis- 

 sipates the theory which obtained credence hitherto in numerous 

 quarters. 



The additions to the Zoological Society's Gardens during the 

 past week include two Laughing Kingfishers (Dacelo gigantea) 

 from Australia, two Hooded Crows {Corvus corax) from Conne- 

 mara, Ireland, presented by Lady Brassey, F.Z. S. ; a Sharp-nosed 

 Crocodile (Crocodilus aculus) from Nicaragua, presented by 

 Mr. C. G. Brown, M.R.C.S. ; a Common Boa (Boa constrictor) 

 from South America, deposited ; a Cook's Phalanger (Phalan- 

 gista cooki 9 ) from Australia, a Globose Curassow (Crax 

 globicera) from Central America, two Stanley Parrakeets (Platy- 

 cercus icterotis jtj.) from Western Australia, purchased; two 

 Long-fronted Gerbilles (Gerbillus longifrons), born in the 

 Gardens. 



OUR ASTRONOMICAL COLUMN 

 An Ancient Occultation of Jupiter.— In Roger de 

 Hoveden's Chronicle, under the year 756, we read: — " Eodem 

 anno Balthere anachorita vitam sanctorum secutus est, et migra- 

 vit ad Dominum ; Luna autem sanguineo rubore superducta 

 octavo Kalendas Decembris quindecima aetate, id et plena, 

 sicque paulatim decrescentibus tenebris ad lucem pristinam per- 

 venit ; nam, mirabiliter, ipsam lunam sequente lucida Stella et 

 pertranseunte tanto spatio earn antecedebat illuminatam, quanto 

 sequebatur, antequam esset obscurata." (Chronica Magistri 

 Rogers de II, redone, edited by William Stubbs, M.A., vol. i. 

 p. 7.) Simeon of Durham records the phenomenon in similar 



terms, and also dates it in A.D. 756 ; but this has been long 

 known to lie a mistake, the eclipse of the monn, to which refer- 

 ence is made, having taken place on the evening of November 23, 

 a.d. 755. 



Calvisius at first supposed that the star which was occulted by 

 the moon at the time of this eclipse might have been the 

 " Oculus Tauri " or Aldebaran, and submitted the point to 

 computation, though, as Pingre remarks, this was unnecessary, 

 as a star with a latitude of more than 5° could not be occulted by 

 an eclipsed moon. Struyck, in the first edition of his well- 

 known geographical and astronomical treatise, published in 1 740, 

 stated that, o 1 calculating the place of the moon, he had found 

 there was no bright star near her at the time, and it occurred to 

 him that perhaps the planet Jupiter might have been occulted 

 by the eclipsed moon, which, on applying " Whiston's Tables," 

 he ascertained to have been actually the case : the tables re- 

 ferred to were those of Halley in their early form. Struyck 

 found the time of the planet's disappearance 6h. 30m. at London, 

 and that of the reappearance 6h. 57m. (see Zach's Monatliche 

 Corrtspondenz, i. 576). 



The following results will probably supply a much closer 

 approximation to the actual circumstances of the phenomenon 

 recorded by the English historians. 



For the elements of the eclipse of the moon we have — 

 G.M.T. of opposition in R.A., 755, November 23, 6h. 25m. 7s. 



R.A 63 3 15 



Moon's hourly motion in R. A. ... ... 3054 



Sun's ,, „ 2 4 1 



Moon's declination 21 4 20 N. 



Suns ,, ... 21 16 37 S. 



Moon's hourly motion in declination .. S 8 N. 



Sun's ,, ,, ,, ... o 2S S. 



Moon's horizontal parallax ... ... 54 16 



Sun's ,, ,, o 9 



Moon's true semi-diameter ... ... 14 47 



Sun's ,, ,, 16 16 



The sidereal time at Greenwich noon was 16I1. 7m. 34s. The 

 moon was full at 6h. 30m. 



From the above elements we find — 



First contact with the shadow 

 Beginning of total phase ... 



End of total phase 



Last contact with the shadow 



Nov. 23, 4 38 



5 47 



„ 7 '8 



8 27 



Employing Bouvard's Tables of Jupiter the following are the 

 positions of the planet : — 



Paris M.T Apparent R.A. Apparent decl. 



h. o - // o ' " 



7 64 23 25 20 50 12 N. 



8 6423 3 2050 9 N. 



The log. distance of Jupiter from the earth was 0-6163. 



Calculating the circumstances of the occultation for London, 

 we find with the above data that the disappearance would take 

 place at 7I1. 35m., and the reappearance at 8h. 33m. ; the 

 former would therefore occur while the moon was still partially 

 i . 1 nd the latter a few minutes after she emerged from the 

 earth's shadow. 



It may be mentioned that the moon's place has been deter- 

 mined in the same manner as for the occultation of Mars 

 observed by the Chinese at Siganfott B.C. 69, February 14, and 

 that of Venus, a.d. 361, March 20, at Nankin, the phenomena 

 being well represented in both cases, as previously detailed in 

 this column. No doubt the introduction of Leverrier's Tables 

 of Jupiter would somewhat modify the times of disappearance 

 and reappearance on November 23, 755, here given ; our object 

 has been merely to confirm Struyck's explanation of the recorded 

 phenomenon. 



ASTRONOMICAL PHENOMENA FOR THE 



WEEK, 1S85, FEBRUARY 22-28 

 (For the reckoning of time the civil day, commencing at 

 Greenwich mean midnight, counting the hours on to 24, is here 

 employed. ) 



At Greenwich on February 22 

 Sun rises, 7I1. im. ; souths, I2h. 13m. 39'6s. ; sets, 17b. 26m. ; 

 decl. on meridian, 10° 1' S. : Sidereal Time at Sunset, 

 3I1. 37m. 



