620 



NATURE 



[October 27, 1892 



his last-mentioned value that has been used in the above re- 

 ductions. The probable error of these determinations is 

 then ±0" '0007 1, which corresponds to ±o"-025 per looo". But 

 Mr. Jacoby does not think that the average uncertainty of the 

 final places exceeds o""i5 on account of scale value. While 

 comparing the Rutherfurd stars with those of Argelander, he 

 found that four stars from the latter were lacking, while they 

 were recorded on the original negatives of the former. Ob- 

 servations made this year showed that three wer: visible, while 

 the fourth (No. 28), which was quite close to No. 27 on the 

 Kutherfurd negatives, was this year "only a sort of elongation 

 of No. 27." On the other hand, the following of Argelander's stars 

 were absent from the plates : — 



B.D. + 27-3395 Mag. 8-8 



+ 27-3414 ., 9-0 



+ 27-3417 „ 9-0 

 and perhaps 



+ 27-3435 „ 8-5 



+ 28-3343 .» 90 



A New Variable Star. — In Astronomische Nachrichten, 

 No. 3124, Prof. Pickering announces the discovery of a new 

 variable star in Aries by Prof. Schaeberle. The fact of this star 

 being a variable was first noted when, on an examination of 

 two plates taken December 18 and January 24, 1891, it was 

 found that on the former it appeared of the 9-5 magnitude, while 

 on the latter it was absent altogether. Recent visual observations 

 have shown, however, a star of the eleventh magnitude in the 

 exact position of the suspected variable, and this has been con- 

 firmed by means of photographs. From photographs of the 

 same region, taken since October 31, 1890, the magnitudes 

 recorded have been 9-6, 102, 1 1 'O, less than 11 7, 10 "i, lo-o, 

 io-4j io'3, and io"9. The star's position for 1900 is given as 

 R.A. 3h. S'Sm. Decl. -J- I4°24'. 



Jupiter's Fifth Satellite.— It hardly ever happens that, 

 after a discovery of any importance has been made, there are 

 not a few " claimants " who wish to annex it as their own. This 

 is the case with Prof. Barnard's discovery of the fifth moon to 

 Jupiter, but the advantage he possesses over these said 

 " claimants " is, we might say, infinite, for it is only with such an 

 instrument as that at the Lick Observatory that this " mite " of 

 a satellite can be observed with success. One of the despatches in 

 which one " claimant's " views were put forth, had the audacity 

 to insinuate that Prof. Barnard was directly inspired to this 

 discovery by information contained in a letter sent to the 

 Observatory. We are glad to see that Prof. Barnari deals with 

 these " claimants" as they deserve, and we hope it may be a 

 lesson to others ■vho wish to assert their priority without good 

 and sufficient reasons for doing so. 



As an illustration of the difficulty of observing this satellite, 

 we may mention that Prof. Young, in a letter to Prof. Barnard, 

 says that although he has used a 23inch Clark, which is an in- 

 strument as nearly perfect as can be made, he was not rewarded 

 with success. 



The Spectrum of Nova Auriga.— Herr E. von Gothard, 

 of the Observatory at Hereny, has taken a very successful 

 photograph of the Nova spectrum, the results of which he com- 

 municates to Astrotiotnische Nachrichten, No. 3122. The in- 

 strument used was a loj-inch reflector with a lo-inch objective 

 prism, and the exposure given amounted to 45 miautes. The 

 spectrum shows six lines, and a comparison with the spectrum 

 of the ring nebula and the Wolf-Kayet stars presented a re- 

 markable concordance, the first failing only in the second Nova 

 line, and the second differing only with regard to the intensity 

 of the individual lines. The following table shows this some- 

 what more clearly : — 



I. II. III. IV. V. VI. VII. 



Nova 6 ... I ... 10 ... 5.3 ... 4 ... — 



G. C. 4964 ... 8 ... 2 ... ID ... 6 ... 6 ... 8 ... — 

 Ring nebula ... 8 ... — ... 5 ... 2 ... 7 .. 6 ... 10 

 The wave-lengths of the lines are, we are sorry to say, not in- 

 serted. 



"Jupiter and His System" is the title of a small book 

 recently published by Mr. Stanford, and written by Miss E. M. 

 Clarke. The authoress has brought -this book out at a time 

 when this planet is receiving most attention, for was it not in 

 opposition, shining with exceeding brightness, on the I2lh of 

 this month? One great point about this little monograph is 



NO. I 200, VOL. 46] 



that facts throughout have been strictly adhered to, so that the 

 reader is presented with the true state of the planet as we know 

 it. The information is well up to date, as for example tin 

 mention of the new satellite, and the book is written in a popa 

 lar yet accurate style. One thing that calls for attention is t he- 

 price (one shilling), which could doubtless have been halved. 



GEOGRAPHICAL NOTES. 

 Mr. J. Y. Buchanan, F.R.S., is this term delivering 1 

 course of lectures on Oceanography in Cambridge University. It 

 is satisfactory to know that the lectures are better attended than 

 has been the case since the foundation of the Geogra]>hy 

 lectureship, and that the greater number of those present this 

 term are undergraduates. 



Mr. Joseph Thomson has submitted to the British Souih 

 Africa Company the report of his journey to the Lake Bangweola 

 region, made last year, which ill-health has prevented him from 

 preparing sooner. He speaks of Northern Zambesia generally 

 as a region of great possibilities. It is a plateau rarely less ihan 

 3500 feet high, with a climate in which Europeans should find 

 no difficulty in living for several years at a time. It is well suited 

 for cattle-rearing and for planting, and there is an appearance 

 of mineral wealth. Like the rest of tropical Africa, the land 

 must be occupied and cultivated, and the natives must be trained 

 to industry before commercial results of any importance can lie 

 o'ltained. 



The special meeting of the Royal Geographical Society to 

 hear Captain Lugard's paper on Uganda will be held on Thurs- 

 day, Nov. 3, at 8.30 p.m. On account of the great popular 

 interest at present being manifested in the region of the Equa- 

 torial lakes, no extra tickets can be issued by the Society, as 

 the attendance of Fellows and their friends will probably more 

 than fill the hall. 



The new number of Petertnann s Mitteihingen contains some 

 articles of considerable interest. Dr. W. Ruge, son of the well- 

 known geographer, Dr. Sophus Ruge, contributes a short but 

 learned treatise on the geography of Asia Minor, which com- 

 bines literary research with personal exploration. Dr. Ernst H. 

 L. Krause produces an interestingmapof North Germany, show- 

 ing the distribution of forests and the most common species of 

 trees during the Middle Ages. This work is accomplished 

 mainly by the consultation of old records, and the examina- 

 tion of the remains of old forests and very ancient trees. The 

 study of history is greatly helped by such a map, and the in- 

 fluence of increasing density of population and extending 

 cultivation of farm crops is brought out strikingly by com- 

 parison with a map of the vegetation at the present day. Dr. 

 Karl Sapper's description of Lake Yzabal in Guatemala is also 

 worthy of note. 



GEIKI ELITE AND BADDELEYITE, TWO 

 NE W MINERAL SPECIES. 

 "W'ARIOUS pebbles were lately brought to this country by 

 ^ Mr. Joseph Baddeley, who has been acting as manager 

 of a Gem and Mining Company in Ceylon. They had been 

 picked up by him in the neighbourhood of Rakwana (Rack- 

 wanne) at various times, and had then attracted his special 

 attention by reason of their high specific gravity. Their real 

 nature not being evident on inspection, Mr. Baddeley, when 

 invalided, brought them home to England for identification. 



One kind of pebble, kindly analyzed for him by Mr. Claudet, 

 was found to be essentially a tantalate of yttrium. 



Pebbles of another kind were taken to the Museum of Prac- 

 tical Geology in Jermyn Street for examination. The external 

 characters being found by Mr. Pringle insufficient for the deter- 

 mination of the species, the pebbles were handed over to Mr. 

 Allan Dick for chemical investigation. Quantitative analysis' 

 proved the mineral to be essentially magnesium titanate 

 (MgTiOa) and chemically analogous to Perofskite, calcium 

 titanate (CaTiOg). To this interesting new species Mr. Dick, 

 in a paper read before the Mineralogical Society in June, gave 

 the name Geikielile, in honour of Sir Archibald Geikie, F.R.S., 

 Director-General of the Geological Survey, in whose laboratory 

 the analysis had been made. 



As described by Mr. Dick, Geikielite has a specific gravity 



