May 5, 1887] 



NATURE 



Although we are unable to give, this week, a complete 

 iccount of the final doings of the Conference, what was 

 ione at the last meeting is partly known, and it is 

 :lear that the Conference has been a great success, and 

 :hat much solid work has been accomplished by the forty 

 :)r fifty astronomers who attended one meeting or the 

 3ther. 



At the final general meeting Admiral Mouchez an- 

 aounced that all necessary arrangements had been made 

 vith the French Government to enable the Observatories 

 >f Paris, Algiers, Bordeaux, and Toulouse, to accept at 

 mce the conditions proposed by the Conference. M. 

 :ruls. Director of the Rio Observatory, and M. Beuf, 

 Director of the La Plata Observatory, also accepted at 

 mce the same conditions ; their instruments being already 

 )rdered, and all expenses provided for. Most of the 

 )fiicial astronomers had not as yet obtained the necessary 

 ,^rants of money from their respective Governments ; but 

 imong those who expressed their readiness to take a 

 share in the work, if funds can be provided, were Struve, 

 )f Pulkova ; Weiss, of Vienna ; Auwers, of Berlin ; 

 :hristie, of Greenwich ; Pujazon, of San Fernando ; 

 3om, of Lisbon ; Gill, of the Cape ; and Russell, of 

 Sydney, who answered also for Ellery, of Melbourne. 

 'rof. Peters, speaking for the United States, said that 

 en of their Observatories were anxious to join in this 

 mdertaking, but he did not know whether they would 

 .ccept the conditions proposed by the Conference. Omit- 

 ing, therefore, these ten doubtful Observatories, we see 

 hat already four Observatories in the North and two in 

 he South have given in their adhesion, and these will 

 robably soon be joined by six other leading Observatories 

 1 the northern hemisphere and by three in the 

 outhern. Henceforward we need have no time or 

 aoney spent on stellar photographs which will not 

 nd their place in a well-thought-out and general 

 cheme. 



The estimated cost for each Observatory, including 

 istruments, extra assistant, plates, measurements, &c., 

 about ^4000. 



We believe that among the resolutions arrived at at the 

 1st meeting was one recommending the erection by 

 ranee of an Observatory at Reunion, and by England of 

 ne in New Zealand. 



The Permanent Committee appointed consists of all 



tie Directors of the Observatories taking part in the work, 



nth a certain number of members not necessarily 



ctually engaged in this work. The names of the Com- 



littee are Christie, Dun^r, Gill, Prosper Henry, Janssen, 



,oewy, Pickering, Struve, Tacchini, \'ogel, Weiss ; and, 



s Directors of Observatories who have decided already 



join, Cruls, Beuf, Mouchez, Trepied, Baillaud, and 



layet. 



The Conference nominated Janssen and Common as a 



ommittee to consider the application of photography to 



ther celestial bodies not included in the scheme of a 



hotographic chart. 



The hospitality of the French Government and men 



science to the members of the Conference can be 



idged from the following list of festivities provided in 



leir honour. In addition to the welcome of the Con- 



irence by the Minister of Foreign Affairs already men- 



oned, Admiral Mouchez gave a soiree at the Observatory 



n Tuesday evening, April 19. The Bureau of the Con- 



jrence were presented to the President of the Republic 



n Wednesday, the 20th. A banquet was given by the 



linister of Foreign Affairs at his official residence, on 



'hursday, the 21st. M. Janssen invited the Conference 



) his Observatory at Meudon on Friday afternoon, the 



2nd. On Saturday there was a ball at the Hotel Con- 



nental and a special performance of " Hamlet " at the 



omddie Frangaise on Sunday. A banquet was given 



y Admiral Mouchez at the Observatory, on Sunday, 



) all the members of the Conference and many of the 



leading French savants, including MM. de Lesseps, 

 Fr^my, Becquerel, Hdbert, and others. On Saturday, 

 the 23rd, the English astronomers gave a dinner to their 

 French confreres ; the Astronomer-Royal presided, Mrs. 

 Christie was also present. 



ON ICE AND BRINES} 



IL 



T^HE second part of the paper is occupied by the 

 ^ study of the melting of pure ice in sea-water and 

 other saline solutions. A large number of experiments 

 were made with solutions of concentration comparable 

 with that of sea-water, and in one or two cases the 

 experiments were extended to low temperatures and 

 strong solutions. As a rule, from 50 to 100 grammes of 

 solution, cooled to o"^ C, were mixed with an equal weight 

 of pounded ice, also at o^ C. The thermometer used for 

 all these determinations was one of Geissler's normal ones, 

 divided into tenths of a degree Centigrade ; and its zero- 

 point was verified almost daily. Along with the ther- 

 mometer, a pipette of suitable capacity was immersed in 

 the beaker, and used with the thermometer for keeping 

 the mass well mixed. Its upper aperture was closed 

 with a small cork, which was removed from time to time 

 to permit of some of the brine being sucked up and 

 allowed to run back again. The inside of the pipette was 

 thus kept constantly moistened with the slowly altering 

 solution in the beaker. The temperature was read after 

 very thorough mixing and the sample thereupon imme- 

 diately removed and preserved for analysis. 



As a rule samples were taken for analysis at intervals 

 of o°-4 C. The results for three classes of salt in dilute 

 solutions are arranged in Tables IV., V., and VI. 



Table IV. — Giving the percentage of chlorine in solutions of 

 various chlorides in which ice melts at given temperatures. 



°c. 

 -35 



-3" 

 -2-5 



-2'0 



-I '5 

 - i"o 

 -0-5 



272 



2IO 



i'47 



Table V. — Giving percentage of K in solutions of various potas' 

 slum salts in which ice melts at given temperatures. 



' Paper read bsfjre the Royal Society of Edinburgh, by J. Y. Buchanan, 

 on March 27 last. Continued from vol. xxxv. p. 611. 



