ya7i. 27, 1876] 



NA TURE 



255 



thousand positions have already been collected— forty thousand 

 for right ascensions and thirty thousand for declinations. Two- 

 thirds of these observations are published, the rest is calculated, 

 and will be printed as soon as the resources of the Observatory 

 permit. For fifty years a series of observations have been carried 

 on in reference to the variations of the mignetic needle at 

 Brussels, the results of which M. Quetclet hopes to be able by 

 and by to publish. He, however, feels that if Brussels is to 

 keep up with the science of the day, much remains to be done. 

 A Commission appointed in 1874 to report on the Observatory 

 gave in their report at the end of that year, and their principal 

 conclusions are as follows : — To complete the magnetic system 

 of the Observatory by the acquisition of self-registering instru- 

 ments, to organise the International Meteorological Service, to 

 obtain an equatorial of large dimensions with the accessories 

 "Ecessary to the spectroscopic investigation of the heavens, and to 

 crease the number and improve the position of the observer. 

 rhe Ministry have, unfortunately, not yet come to a decision on 

 :hcse conclusions, though we hope they may do so soon, and 

 enable the valuable work of the Observatory to be carried on 

 with coaapkte efficiency, and the results be regularly given to 

 the scientific world. Meanwhile, the work of the Observatory 

 is being regularly carried on on the old lines. 



The new Aquarium at Westminster was opened on Saturday 

 \ ~.st by the Duke of Edinburgh ; but though the building is 

 jfnciently complete for concerts to be held, it will be many 

 weeks before the tanks are in a proper condition to receive water. 

 The arrangements connected with the aquarium proper have been 

 mider the direction of Mr. W. A. Lloyd, whophnned the Crystal 

 Palace ani other aquaria. There are in this latest development 

 of aquarium construction two or three new points worthy of 

 attention. The water in flowing from one tank to another will 

 overflow from one and pass down a tube, so that it enters the next 

 at the bottom, by which means a more thorough mixture than has 

 hitherto been attained will be ensured of the wa'er that has been 

 exposed to the surface aeration. The reservoir which occupies 

 the space under the large hall is divided into nine compartments, 

 so that in case of an accident to any part, it can be cleared of 

 the water and repaired while the other sections remain in opera- 

 tion. The total capacity of the reservoir is 600,000 gallons, and 

 the total amount of water in reservoir and tanks together will be 

 750,000 gallons. For the circulation eight rotary vulcanite 

 v.mps are erected, and they are capable of sending 56,000 

 .lions an hour through the tanks if needed, to meet any 

 mergency, though it is calculated that 15,000 to 20,000 gallons 

 '.ill be about the average amount. The plan of forcing down- 

 wards small jets of water into each tank, as at the Crystal 

 Palace, is adopted. In the anemone tanks the water will be 

 periodically emptied, representing, to some extent, tidal action. 

 The salmon will have a fifty-feet run, and so wUl the \\Tasse. All 

 he pipes, culverts, &c., areof vulcanite, but the glass fronts of the 

 inks are fitted in cork, with the exception of some of the lime- 

 one rock-work, which may probably be too soluble ; everything 

 "lat forethought could arrange in accordance with our present 

 nowledge seems to have been attended to. It is to be hoped 

 '.at the scientific residts obtained will not be out of proportion 

 'i the cost of the undertaking. The ofticial guide-book pub- 

 jished on Saturday contains a useful article on aquarium manage- 

 ment by Mr, Lloyd, and the Gardeners' Magazine of last week 

 has also a contribution from his pen on the rise and progress 

 of aquaria in England ; the Morning Post of Saturday last con- 

 tained an interesting article. The cover of the ofiicial guide* 

 book is ornamented with a wcodcut by Tenniel, which is quite 

 equal to hi$ happiest eflForts in Punch. 



The Committee of Science of the Irish Academy will meet 

 on Feb. 28 to take into consideration apphcations for assist- 



ance out of the parliamentary grant for the preparation kA 

 scientific reports ; and it is requested that all such applications 

 be forwarded to the secretary on or before that date. 



The Montsouris Observatory has been supplied with a number 

 of recording apparatuses for barometric pressures constructed on 

 new principles, and instruments for recording thermometric 

 variations have been made on aneroid and bi-metallic principles. 

 A steel needle guided by these dilatations traces a curve on a 

 rotating cylinder. The anemometer records by a magnetic con- 

 trivance devised by M. Mangon. M. Marie Davy has also 

 established " an apparatus for recording the pressure exerted 

 by the wind. A specially devised mirror has been arranged to 

 indicate the direction of the clouds, which it is rather difficult to 

 discover from direct inspection of the clouds themselve?. 



Dr. Samuel Birch has been appointed to the Rede Lec- 

 tureship in the University of Cambridge. He will deliver his 

 lecture about Easter. 



At the January meeting of the Photographic Society, the hon. 

 secretary read a note on the action of eosin on the photographic 

 spectrum, by Captain J. Waterhouse, B.S.C., assistant surveyor- 

 general of India. Tetrabromfluorescin, or eosin as it is termed 

 commercially, is a dye remarkable for its intense fluorescence 

 and beautiful pink colour. Its absorption spectrum is charac- 

 terised by a very strong band between E and F, which fades off 

 on either side and terminates half way between D and E, and 

 ha'f way between F and G. At the part of the spectrum 

 indicated, photographic action was increased to a marked 

 degree when the collodion was stained with the dye. Captain 

 Waterhouse naturally inferred that greens, e.g. foliage, would 

 exhibit more detail if photographed on eosin-stained plates, but 

 this was not the case, the only effect was to make the whole 

 action of the light slower. Vogel's observations have thus been 

 confirmed so far as the spectrum effects are concerned ; the want 

 of action when coloured surfaces are photographed is however 

 at variance with his results obtained, we believe, by photo- 

 graphing coloured papers. By the kindness of Mr. John SpUler, 

 to whom Captain Waterhouse's letter was addressed, we have 

 been enabled to see some of his spectrum photographs, and they 

 certainly surpass any results of the kind we have yet seen. 



The Journal (VHygilne, No, 8, of Dr. Prosper de Pietra 

 Santa, contains several articles of interest. The Climat de Pan 

 gives a brief resumi of the meteorological characteristics of this 

 place, in which special prominence is given to the chief feature 

 of its climate, viz. the remarkable calmness of its atmosphere, 

 which, combined with a light porous soil draining away the 

 rains as they fall, and'the great beauty of its environs, have made 

 the reputation of Pau as a desirable winter and spring sanata- 

 rium. In V Emigration dans U Midi de la France attention is 

 directed to the varied climates of France in their therapeutic 

 relations, which are classed, according to their characteristics in 

 these respects, into sea-climates, such as Cannes, Menton, 

 Ajaccio, and parts of Nice, Hyeres, and Alger ; hill climates, 

 such as Pau, Orthez, Le Cannet, and parts of Nice, Hyere?, 

 and Alger; and mixed or intermediate climates, such as Arcachon, 

 Vemet, and Amelie-les-Bain. The determination landward of 

 sea climates which are considered as consisting in an atmosphere 

 containing a minimum of miasmatic matters, a maximum of 

 oxygen, the air impregnated with fine particles of chloride of 

 sodium, and with a peculiar odour derived from marine plants 

 charged with bromine and iodine, is a point of considerable im- 

 portance. 



The Bulletin International of the Paris Observatory of the 

 18th inst. is the first number of a new issue, executed by the 

 printing establishment of MM. Yves and Barrel, by the process 

 of photo-engraving, of which a brief account is given. The 



