20 



NATURE 



[Nov. 6, 1879 



industry affords employment to upwards of 200 small vessels. A 

 diving apparatus is used in fishing for sponges; the produce 

 during the season is between 25,000 and 35,000 sponges. A 

 duty of 40/. is levied by Government on each diving apparatus 

 and 10/. on every vessel not carrying that appliance. The pro- 

 duce of the sponge fishery last year was estimated to be worth 

 about 15,000/., and was exported chiefly to England. 



Messrs. Francis and Co., of Hatton Garden, have recently 

 devised an extremely useful telegraphic arrangement for ships, 

 by which instant communication is given by the captain or officer 

 of the watch to the helmsman. For the navigation of rivers and 

 small waters such means of rapid telegraphing with the man at 

 the helm must be invaluable, as in an instant an order can be 

 given, and that, too, with absolute certainty. A leading and 

 important feature in this new invention is that the signals to 

 every part of the ship can Xsi given from the one instrument, 

 which is in form like a handsome capstan, with the commutators 

 so arranged horizontally around its head that it may be worked 

 by any one without the least instruction. 



A COURSE of elementary lectures in continuation of a descrip- 

 tion of the solar system will be delivered in the theatre of 

 Gresham College, Basinghall Street, London, E.C., on the 

 evenings of November II, 12, 13, and 14, by the Rev. E. 

 Ledger, M.A., F.R.A.S., Gresham Professor of Astronomy. 

 The lectures will be delivered at 6 o'clock P.M., and will be free 

 to the public. They will be illustrated by means of a lime light. 



As we have announced, the three Parisian telephonic 

 companies have entered into a working arrangement, and are 

 busy settling the details. In consequence of this fusion the 

 subscriptions have ceased to be received, the future common 

 price having not yet been agreed 'upon. It is certain that 

 it will be dearer than the cheapest, and cheaper than the dearest. 

 According to every probability 600 francs a year for a single 

 line. 



The gold discoveries in the north of New Caledonia are 

 reported to be turning out very valuable. 



From Japan we hear that the manufacture of sulphuric acid 

 is now being extensively carried on at the Osaka Mint, and large 

 quantities are exported to China. 



Three boa-constrictors, found in the Chinese island of 

 Hainan, have lately been presented to the Botanical Gardens at 

 Hong Kong. 



We learn from a report on the trade and navigation of New 

 York for 1S7S that grape-sugar is being largely manufactured at 

 Buffalo, three large factories have been established for the manu- 

 facture of glucose in a solid and liquid form, 200,000 to 300,000 

 bushels of corn being used in them per month. This product 

 has a ready sale and is largely exported to Europe and other 

 countries, and the business is said to be a very profitable one. 



The principal papers in the Thirteenth Annual Report of the 

 Aeronautical Society are on the Flight of Birds, by Mr. Brearey 

 and Mr. H. Sutton. 



The report of the meeting of October 17 of the Eastbourne 

 Natural History Society contains a paper "On the Additions to 

 the Fauna and Flora of the Cockmere District during the past 

 year," by Mr. F. C. S. Roper. 



The additions to the Zoological Society's Gardens during the 

 past week include a Weeper Capuchin (Cebtts capucinus) from 

 South America, presented by Mr. A. Sargent ; a Silver Pheasant 

 (Euflocamiis nycthcnierus) from China, presented by Mr. R. 

 Moon ; three Common Boas (Boa constrictor) from Bahia, pre- 

 sented by Mr. W. Yonng ; a Bosnian's Potto (Pcrodicticus fotto) 

 from West Africa, four Pied Wagtails (Molacilla yarrcllii), 

 British, purchased. 



OUR ASTRONOMICAL COLUMN 



Minor Planets in 1SS0.— In the first half of the ensuing 

 year three out of the four older minor planets, viz, Certs, Pallas, 

 and Vesta will come into opposition while not far from peri- 

 helion, and consequently their angular diameters and brightness 

 will be about as great as they ever can be, thus : — 

 Pallas in opposition on Jan. 12 will be in perihelion on Feb. 23. 

 Ceres „ „ Feb. 12 „ „ Feb. 18. 



Vesta „ „ June 2 ,, ,, June 19. 



At opposition the brightness of Pallas will be 6 - 8m., that of 

 Ceres 7 3m., and that of Vesta 6"om. 



Perhaps advantage may be taken of the favourable conditions 

 attaching to the positions of these planets to ascertain if they do 

 really present measurable disks as has been stated by Lamont in 

 the case of Pallas, and by Secchi in that of Vesta. Lamont, 

 soon after the mounting of the 11 -inch refractor at Munich, on a 

 night of exceptional clearness, found that Pallas presented a 

 defined disk, which at the mean distance of the planet from the 

 sun would subtend an angle of o"'5l, which would correspond to 

 l"'4l at the distance unity. Again, Secchi observing on nights 

 near the opposition of Vesta in 1855, noted a disk a little less 

 than is presented by Jupiter's first satellite, or about o"'8, which 

 at the earth's mean distance from the sun would subtend I "'01. 

 There is a third instance in the case of one of the rnore- 

 recently discovered planets, Iris, which at the close opposi- 

 tion in the winter of 1S66, was measured by Mr. Talma.e 

 with Mr. J. G. Barclay's 10-inch refractor at Leyton ; he found 

 the apparent diameter o"'a6, or the diameter at distance 

 unity o"'8q. Hence we should have for the real diameters 630 

 miles for Pallas, 450 miles for Vesta, and 400 miles for Iris, 

 dimensions beyond those which have been attributed to them on 

 other grounds. The south declinations of Pallas and Vesta will 

 render them fitting objects for examination at Melbourne should 

 Mr. Ellery be disposed to try the powers of his great reflector 

 upon them. Ceres will be well observable in this hemisphere. 



While writing upon minor planets it may be mentioned that 

 their number has now been increased to 207 ; a circular from 

 Prof. Peters, of Kiel, notifying the discovery of four new ones 

 at Clinton (New York) and at Pola, by Prof. C. H. F. Peters 

 and Herr Palisa. 



The Red Spot upon Jupiter. — Dr. O. Lohse, of the 

 Physical Observatory at Potsdam, who has watched this planet 

 regularly during the last nine years, mentions that on June 5, 

 when his observations of the present year commenced, the red spot 

 was of an intensity of colour to be perceived at the first glance 

 at 15I1. m.t., when it was near the eastern limb. The sharp out- 

 line and the form of the spot appearing to offer an advantageous 

 opportunity for another determination of the time of rotation, 

 numerous estimations and some measures of its position and size 

 have been made at Potsdam. Dr. Lohse does not refer to any 

 suspicion of proper motion, of which we have heard elsewhere, 

 but, on the contrary, states that, with the rotation- period, 

 9"922ih., added on to the epoch 1879, September 27, at gh. 

 48'3m., Berlin M.T. (or 8h. 547m. G.M.T.), the successive 

 times of transit of the middle of the spot over the central 

 meridian may be obtained. From sensible variation in the in- 

 tensity and tint near the centre and limbs of [the planet he con- 

 jectures the superposition of very dense gas or vapour. As the 

 spot exhibits remarkable permanence, it may be also observable 

 next year, and thus be the means of fixing the period of rota- 

 tion with precision. Dr. Lohse further notes that this remarkable 

 appearance upon the disk of Jupiter takes place at the time of 

 recommencement of activity in the solar atmosphere. 



A Standard Clock at the Observatory, Strassburg. — 

 Those who give attention to horological matters will note with 

 interest a communication from Prof. Winnecke, Director of the 

 Imperial Observatory at Strassburg, on the performance of a 

 clock constructed for that establishment by Hohwii, of Amster- 

 dam. The observed rates between 1875 and 1878 are exhibited 

 in tabular form, and are compared with rates calculated from a 

 formula which Dr. Schur has investigated, viz. : — 



Daily rate = o'ooo + 0-0125 (* "" 75°) ~ °' 01 10 (' ~ 20 )» 

 where b is the height of the barometer in millimetres and t the 

 temperature in the clock-case expressed in degrees of Celsius. 

 The tabular statement (Ast. JVacA., No. 2,282) is much too long 

 to be reproduced here, but we make the following extract show- 

 ing the observed and computed rates applying to the two-months' 



