March 5, 1885] 



NA TURE 



419 



into sweet water, and even the Abacus pachypus, Rathke, 

 of the mountain-lake Abrau, is a remainder of a maritime 

 fauna ; so also Thelphusa, which has gigantic representatives 

 in the South Caspian. Certain crabs reach really gigantic size 

 in the Ponto-Caspian region ; such as Eriphia spinifrons and 

 Carcinus nurnas on the shores of Crimea and at Odessa. W hile 

 most crabs reach a great development only in very salt and warm 

 water, others reach the same size under the influence of reverse 

 conditions. The Decapods of the Azov Sea have not yet been 

 explored. The descriptions of the species and their varieties 

 being given in Latin, as also the explanations to the plates, the 

 work is rendered accessible to all zoologists, many of whom, 

 however, will regret not to be able to understand the notes 

 (mostly zoo-topographical, and sometimes adding minor details 

 to the description), which are in Russian. 



We have received from the Johns Hopkins University the two 

 last of the Studies on Historical and Political Science. One 

 deals with land laws in mining districts, and describes the regu- 

 lations for the use of land made by agreement among the miners 

 themselves in the Western States. They show a return to 

 primitive ideas, where use is made the proof of ownership, and 

 equality in the size of the various lots is of prime importance. 

 Mr. Shinn is the author of this number. The second, by the 

 editor, Dr. Adams, describes the influence of the State of Mary- 

 land upon the land cessions of the United States, and is specially 

 interesting for its references to Washington's project for devoting 

 the present made to him by his native State, Virginia, to the 

 establishment of a National University. 



With the exception of a few pages, the whole of the last 

 number (vol. vi. No. 4) of the Boletin de 'a Acatiimia National 

 de Ciencias of Cordova ( Argentine Republic) is occupied by a 

 paper by M. Oscar Dcering on meteorological observations made 

 by him at Cordova during 1883. The-e were a continuation of 

 those made by him in 1882 on evaporation, and the various 

 temperatures at six different depths. But for 1883 he has added 

 other observations and arranged the tables as follows : — Atmo- 

 spheric pressure, temperature of the air, the elastic force ■ f the 

 atmospheric vapour, relative humidity, evaporation in the shade 

 and in the sun, temperature of the soil, solar radiation, storms, 

 and rainfall. There is also a short paper on the observations of 

 the German expedition to Babia Blanca, to observe the transit 

 of Venus. 



The additions to the Zoological Society's Gardens during the 

 past week include two Wood Hares (Lepus syhalkus) from 

 North America, presented by Mr. F. J. Thompson ; an Alex- 

 andrine Parrakeet (PaUeornis altxandri V ) from India, pre- 

 sented by Mr. W. Hay ; a Common Magpie (Pi:a nistica), 

 British, presented by Mr. II. Clare; a Slowworm (Anguh 

 fragilis), British, presented by Mr. R. ( iunter ; a Short-tailed 

 Wallaby (Halmaturus irac&vurus) from Western Australia, 

 deposited; two Brown Pelicans (Pelecanus fuscus) from the 

 West Indies, purchased ; an Isabelline Lynx (Felis isabellina & ) 

 from Tibet, received in exchange , two Spotted Ichneumons 

 (Ilcrptstes nepalensis) from Assam, received on approval. 



OUR ASTRONOMICAL COLUMN 

 A Comet in 1717. — In a note to the Royal Society (Phil. 

 Trans., No. 354) Halley reported that on Monday, June 10, 

 1 71 7, in the evening, the sly being very serene and calm, he 

 was desirous of examining Mars, then very near the earth, to 

 ascertain whether in his 20-foot telescope he could distinguish 

 the spot said to be seen upon his disk, and directing his tele- 

 scope for that purpose he accidentally met with a small whitish 

 appearance near the planet, which seemed to emit from its upper 

 part a short kind of radiation, directed neatly towards the point 

 opposite to the sun. The great light of the moon, then not far 

 from full, and close at hand, hindered the object from being 



distinctly seen, but he determined its place to be nearly 

 in 1 7" 12' of Sagittarius with 4° 12' south latitude. The position, 

 he adds, would be more exactly found by means of two small 

 stars near it, the more northerly of which had the same latitude 

 and followed at the distance of about six minutes ; the other was 

 about four minutes south of the former, and followed it about a 

 minute, "the angle at the northern star was somewhat obtuse, 

 of about 100 degrees, and the distance of the nebula from it 

 was se quialteral to the distance of the two stars, or rather a 

 little more." No motion being detected in over one hour, Halley 

 doubted if it were a comet, but on June 15, the moon being 

 down and the sky clear, he had a distinct view of the two stars, 

 but there was no sign of the nebulosity where it had been 

 observed on June 10. He was led by this circumstance to 

 remark upon the number of comets which might escape notice, 

 from their being telescopic objects, and adds that, although comets 

 had been seen elsewhere in 1698, 1699, 1702, and 1707, he could 

 not learn that any comet had been perceived in this country for 

 the thirty-five years previous to the observation above described, 

 which implies that none had been seen here since the year 16S2, 

 that of the appearance of the famous comet which bears 

 Halley's name. 



The small stars to which Halley refers would appear to be 

 Nos. 16,627 and '6,631 in Oeltzen's Argelander. 



Tin Variable Star S Cancri. — A minimum of this short- 

 period variable being due during the night of February 20, Mr. 

 Knott availed himself of a fine sky at Cuckfield toobserve it as long 

 as it was possible to do so. The watch commenced at 8h. 40m., 

 and ended at 17I1. 15m. At oh. 23m. no change was notice- 

 able, but soon after gh. 30m. the star began to decline, and 

 gradually fell from 8 - l to 10-4 uiag , which point was reached 

 about 15b. 30m. From that time till 17I1. 15m. no certain 

 change was detected, though at 17I1. 15m. there was a suspicion 

 of the star being possibly a trifle blighter. By this time it was 

 17I1. past the meridian, and getting too low for observation. 

 As it was not possible to follow the star till its advance on the 

 rising curve, Mr. Knott was unable to fix the time of minimum 

 with certainty, but considered the predie'ed time (16I1. 22m ) 

 was pretty correct. He remarks further tbat Prof. Schdnfeld 

 gives 8ih. as the time of decrease, and 13I1. as that of increase. 

 If this held for the minimum of February 20, and the decrease 

 began at 9h. 30m., the minimum would not be reached before 

 i8h., and the normal magnitude would not be attained before 

 February 21, Sh. At 6h. 30m. on the latter date he doubted 

 whether' the star had recovered its normal brightness, but by 7I1. 

 or 7h. 30m. there seemed no doubt about it. Comparing the 

 form of his curve with Prof. Schonfeld's, it appeared that on 

 this occasion the star was longer in falling from 94 and 9 '9 m. 

 to the lowest point reached, than the observations of Prof. 

 Schdnfeld indicated ; but Mr. Knott writes doubtfully upon this 

 point, not having previously watched S Cancri through its 

 changes. The next minimum may be expected on March II, 

 between 15I1. and 16I1. Greenwich time. 



The Melbourne Observatory. — We have received the 

 nineteenth annual report of the Government Astronomer of 

 Victoria to the Board of Visitors of the Melbourne Observatory. 

 The new transit circle of 8 inches aperture, constructed for that 

 establishment by Mr. Simms, was received in May last, and the 

 mounting was completed early in July. At the time of drawing 

 up the report (August, 18S4) there were only wanting some 

 steps and observing chairs, for the instrument to be brought into 

 regular use. It is stated to be very similar in form and dimen- 

 sions to the transit circles constructed by the same firm for the 

 observatory at Cambridge and for that of Harvard College, 

 U.S. The great reflector was in better condition than at the 

 date of the previous report, nevertheless it is proposed to send 

 the two specula, one after the other, to England, to be re- 

 polished. A number of stars selected by Prof. Auwers had 

 ived with the old transit circle, to assist in the forma- 

 tion oi 1 fundamental catalogue of southern stars. Mr. Ellery 

 mentions thoseof Herschel's nebulre, which had been ob-erved, 

 and of which drawings had been made with the great telescope ; 

 the nebula of?) Argus, 30 Doradus, and the "Horseshoe" 

 nebula are included in his list. Pons' comet was observed for 

 position from January 6 to MachiS. The completion of the 

 . [1 it determination of Australian longitudes, it is re- 



ported, was only waiting a new series of exchanges between 

 Sydney, Adelaide, and Melbourne; New Zealand had been 

 connected with Sydney by a most successful set of time- 

 through the cable. The connection of Brisbane 



