10 



NATURE 



[May 21, 1 89 1 



THE PARIS OBSERVATORY^ 



THIS report opens with the address delivered by the Director, 

 Admiral Mouchez, before the Council of the Observatory 

 on February 24 last ; the follow^ing is a brief summary of the 

 most important points touched upon. 



After referring to the successful completion of the building 

 for the large equatorial cotidS, in which the instrument is now 

 being erected, and to the formation of a special service for 

 spectroscopy, over which M. Deslandres has been put in charge, 

 he enters on the question of the formation of a branch establish- 

 ment outside Paris. "The demands of modern science," he 

 says, "the extreme smallness of the quantities on which the 

 astronomy of position depends, and the extreme faintness of 

 the objects that physical astronomy studies in order to penetrate 

 more and more deeply into the knowledge of the universe, admit 

 indeed of new processes of observation of such delicacy that 

 they are altogether incompatible with the turmoil and dis- 

 turbances of all kinds in a populous city. The instruments with 

 large optical power lose nearly all their superiority, because they 

 magnify the defects of an impure and disturbed atmosphere at 

 least as rapidly as the images of the stars." 



This is by no means the first time that this question of a 

 branch establishment has been raised, but it looks very much 

 as if it might now be taken up seriously. It seems that a 

 proposal has been made to extend the railroad from Sceaux- 

 Limours in the interior of Paris to Medicis and Cluny, where it 

 would join the metropolitan ; if this project was carried out, 

 trains would run as close to the Observatory as 150 metres, thus 

 affording the assistants at the Observatory an interesting amuse- 

 ment in calculating the distances of these trains by the vibrations 

 set up in the various instiuments. 



A committee of inquiry, presided over by M. Chauchat, has 

 been formed to inquire into the situation, and the unanimous 

 opinion of all the astronomers questioned on the subject was that 

 "the Observatory would be almost lost if this project was 

 carried out according to the present conditions," 



Of the other arguments put forward by Admiral Mouchez in 

 favour of the branch establishment, the following may be 

 mentioned. The lighting of the surrounding streets by means 

 of the electric light. This, as he says, would obliterate all stars 

 above the 12th magnitude, and perhaps even above the li^th, 

 to say nothing of the minor.planets, nebulae, and some comets. 

 And with regard to photographing the heavens with moderate 

 exposures, it would become nearly impossible owing to the 

 fogging of the plates before the images are formed, the gas from 

 the street lamps even now producing this effect on the sensitized 

 plates. Referring to the opening and enlarging of the Rue 

 Cassini, he points out, that at no remote date, houses will be 

 constructed from 20 metres to 25 metres in height at a distance 

 of 100 metres, and just in the direction of the meridian line of 

 the instruments ; these, besides completely blotting out from 

 view many of the circumpolar stars at their lower culmination, 

 will render the observation of those that remain difficult on 

 account of the smoke from the chimneys. 



Following Admiral Mouchez's address are the reports, from 

 each of the heads of the various departments, of the work done 

 during the past year. With the meridian circle no less than 

 14,374 stars have been observed, exclusive of the 432 observa- 

 tions of the planets made with the same instrument. Ob- 

 servations which were commenced in the month of April with 

 the equatorial coude, have been regularly pursued, and at present 

 the results have been highly satisfactory. Not only "do we 

 believe that we have settled in every detail the most precise 

 rules for the application of the new method, but also we have 

 obtained the constant of aberration with an exactness which 

 surpasses all researches made up to the present time," 



The three equatorials have been used by M. Bigourdan, 

 Mdlle, Klumpke, and M. Boinot respectively, and with them 

 observations have been made of comets, double stars, nebulas, 

 eclipses of Jupiter's satellites, occultations, planets, and double 

 stars. 



M. Paul Henry, who is chief of the photographic department, 

 has been busily engaged among other things in making large 

 cliches of different regions of the sky, several of which were 

 prepared at the request of foreign astronomers. 



The most important addition to the Observatory for the year 



' " Rapport Annuel sur I'Etat de I'Observatoire de Paris pour I'Ann^e 

 1890." Presente au Conseil par M, le Contre-Amiral Mouchez. (Paris: 

 Gauthier-Villars et Fils, 1891.) 



NO. II 25, VOL. 44] 



was the special service for stellar spectroscopy, which, as we 

 have mentioned before, is superintended by M, Deslandres, 

 This branch, when in full working order, should be of the 

 utmost value to science, and the results obtained will be looked 

 forward tn with interest. With regard to this branch Admiral 

 Mouchez has given an extract from M. Deslandres' report on 

 the installation of the apparatus and the results obtained. 



After a short description of the meteorological work carried 

 on, together with the various other reports usually inserted in 

 this pamphlet. Admiral Mouchez concludes with a brief reference 

 to the Observatory School at Montsouris, of which also he is 

 Director, This school was organized under the patronage of 

 the Bureau of Longitudes, in order to supply a want long felt in 

 France of a school for practical astronomy, where "marine 

 officers, explorers, professors of science, and others could come 

 and accustom themselves to make observations." Since the 

 year 1877 the Observatory has been freely opened to anyone, the 

 only conditions being that those who go should have sufficient 

 scientific knowledge to understand what is taught, and that 

 their work should be regular. To give an idea of the range of 

 the subjects that form the syllabus of instruction we cannot do 

 better than condense the methods of organization as given in the 

 report. 



With regard to astronomy, both theoretical and practical 

 lectures are given twice or three times a week. M. Boitel 

 delivers a course on electricity and magnetism which extends 

 over four months, during which time he conducts the officers 

 over all the large electrical manufactories in Paris. Lectures 

 on meteorology are delivered by M. Moureaux, who concludes 

 them with practical instructions for the determination of the 

 magnetic elements. M, Thoulet treats of ocean geography 

 in a course that is of interest and use to sailors. The regulation 

 of the compass, so important to-day on account of our iron ships, 

 forms the subject of a number of lectures by M. Caspari, while 

 photography is studied for two months under the superintendence 

 of M. Guenaire. 



From this syllabus it will be seen that a good, practical, and 

 sound course is open to all those who wish to take advantage of 

 it, and in the list of explorers who have figured in thfi principal 

 missions during the last fifteen years the majority will be found 

 to have served at any rate a short period at the Observatory 

 School. 



In concluding his remarks. Admiral Mouchez, after referring 

 to the school that was started in 1879, and which was suppressed 

 some years after for reasons of economy, points out the necessity 

 of giving every encouragement to the one that is doing such 

 good work at Montsouris. W. J. L. 



NOTE ON THE PHYSIOLOGICAL ACTION OF 

 CARBON-MONOXIDE OF NICKEL [Ni(CO)i].^ 



"DY the kindness of Mr. Ludwig Mond, we have had the 

 ^ opportunity of examining the physiological action of car- 

 bon-monoxide of nickel, a substance of unique chemical com- 

 position, represented by the formula Ni(C0)4. The general 

 results of our investigation are as follows : — 



(i) Ni(C0)4 is a powerful poison when injected subcutaneously 

 into a rabbit weighing i'5 kilo, even with a dose of i/30th ccm, 



(2) The vapour of Ni(C0)4 in air, even to the extent of 0*5 per 

 cent., is dangerous, 



(3) The symptoms are those of a respiratory poison, and are 

 similar to those caused by carbonic oxide, 



(4) The spectrum of the blood of an animal poisoned by 

 Ni(CO)4 is that of carbonic oxide-haemoglobin, and it is not 

 reduced by sulphide of ammonium. 



(5) When the substance is injected subcutaneously it is 

 probably in part dissociated in the tissues, as there is evidence of 

 the existence of nickel in those tissues, but the nickel also finds 

 its way into the blood, and is found there, 



(6) The substance produces a remarkably prolonged fall of 

 temperature even when given in small quantities. In several 

 instances, with lethal doses, the fall was from 2° to 12° C, This 

 may be accounted for by the haemoglobin being prevented to a 

 large extent from supplying the tissues with oxygen. Nico, as we 

 may, for convenience, call this substance, makes it possible to give 

 graduated doses of carbonic oxide, and thus reduce temperature 



' By John G. McKendrick, M.D., F.R.S., and William Snodgrass, M.A. 

 M.B., Physiological Laboratory, University of Glasgow. 



