236 



NA TURE 



\Jnly 6, 188: 



whilst they are pursuing their studies in this institution. We 

 have also twelve exhibitions of 50/., four of 15/., and two of 

 25/., which are awarded annually by the Government. These 

 are only the nucleus, so to speak, of numbers of exhibitions 

 which are given in various localities, and that bring to this insti- 

 tion for training, the men who have the faculty for science 

 teaching, and who will be the future teachers for science in this 

 country. I am sure no one can have been present to-day, and 

 have seen those young men advance to the table, and have seen 

 them receive their certificates of associateship, and their honour- 

 able awards for their successful studies, without feeling that 

 those men are going to carry to all the centres of industry an 

 amount of light and knowledge which will be of immense ad- 

 vantage, not only to themselves, but to the industry with which 

 they are associated. In every part of England there is a 

 demand for technical instruction, and that demand is very much 

 groping iu the dark, for our people hardly understand what they 

 mean by it yet. It means they want to know the rationale of 

 the work which they are doing. They are tired of working by 

 rule of thumb, that when, as I have heard a Dyer explain how 

 he got certain results, he tried bis alkalies and acids by dipping 

 his thumb into them and tasting them, and when he found the 

 components for some particular dye, he took a shovelful of this 

 and a shovelful of the other, and so arrived at certain result;; 

 which he could rarely arrive at with precision again, but which 

 was mere guesswork, rule of thumb, chance, and accident ; all 

 that is passing away, and I believe, as the result of the good 

 work that is doing in this institution. I am sure you will all 

 join with me in expressing the hope that our Dean, who holds 

 that title for the first time during the last year, will long remain 

 at the head of this institution, to carry it to that success to 

 which he aspires, and which he has done his utmost, by his 

 noble effort and by his constant and eloquent advocacy, to 

 secure. > 



DUNS INK OBSERVATORY 1 

 A/TR. DREYER, having been appointed to succeed the late 

 •*■ Dr. T. Romney Robinson as director of the Armagh Obser- 

 vatory, will vacate his post here next September. An advertise 

 ment has been inserted in Nature inviting applications for the 

 post of assistant. I have received a number of replies, but I am 

 not yet in a position to make a definite recommendation. I do 

 not like to allow Mr. Dreyer's resignation to pass without ex- 

 pressing the high opinion I have of the manner in which his 

 duties here were discharged. 



The meridian circle has been as before in the entire charge of 

 Mr. Dreyer. During the past year Part IV. of the Dunsink 

 Observations and Researches has been issued, in which is con- 

 tained an account of the meridian circle and a catalogue of the 

 red stars whose places have been determined. In July and 

 August many nights were spent observing the two bright comets, 

 but the weather was so unsettled that only four observations of 

 Comet III. and two of Comet IV. could be secured on the 

 meridian. 



In September a series of observations of stars between -2° 

 and - 23 declination were commenced. In all there have been 

 made 713 observations of transits, and 582 observations of decli- 

 nation ; the reductions to apparent place are completed for R. A. 

 up to December 1 1, ami for deck up to March 10. 



The meantime clock service has been continued throughout 

 the year. The circuit has been tested on 349 days— from July 1 

 up to June 14 — with the following results : — 



265 days' error not greater than I sec. 

 56 ,, between 1 sec. and 2 sees. 



28 ,, greater than 2 sees. 



I referred in my last report to the chronograph which Mr. 

 Grubb has had in hand. From a great press of other work, 

 the instrument has not yet been quite finished, but I think we 

 may now regard the chief difficulties as conquered, and I look 

 forward very shortly to having a chronograph which will enable 

 us to do real justice to the meridian circle. 



The South Equatorial has, as before, been chiefly employed 

 by myself in the observations of stars for annual parallax. The 

 number of the observations made altogether amount to 1S6. 

 This number is less than that in former years, because several 



1 Report on the Work of the Dunsink Observatory between July 6, iSSr, 

 and June 26, 1882, made to the Board of 'trinity College, Dublin, at the 

 Annual Visitation on June 27, 1882. By Prof. Robert S. Ball, LL.D., 

 F.R. S., Royal Astronomer of Ireland. 



series of observations have been brought to a close during ihe 

 present year, and the results have been discussed and prepared 

 for publication. I now submit the manuscript which is ready 

 for the press as Part V. of our publications. The work will be 

 considerably larger than the parts formerly issued, and will con- 

 tain 200 pages or somewhat more. It consists entirely of the 

 parallax researches made by myself at the South Equatorial in 

 the last four years, and brief abstracts haveoccasionally appeared 

 elsewhere. I now only glance at the portions completed since 

 the last visitation. 



In my last report I stated that the measures of the position 

 angle of +50 , 1724, from Groombridge, 1618, required further 

 discussion : that di-cussion they have since received, and the 

 result is very satisfactory. From the distances I had obtained 

 from Gr. 161S a parallax of 



o"-334± -036. 

 From the position angles the discussion now submitted gives a 

 parallax of 



o"-3i4±-03l. 

 By combining these results, we find as the result of 106 nights ot 

 observation the mean value 



o' ,- 322 ± , 0"'028. 

 Considering the smallness of the probable error, it can hardly be 

 doubted that this object has a parallax of a third of a s econd. 



I also submit the completely discussed observations of 368 

 stars which have been examined in the manner already described as 

 reconnoitring fur annual parallax. In the great majority of cases 

 the results are negative, yet even in these cases I believe the 

 work is of value as a part of the general survey of the heavens. 

 It is also, I believe, the only systematic effort which has yet been 

 made to search for the nearest neighbours of the sun. 



I am, however, glad to say that all the results of this work 

 are not purely negative, but that certainly in one instance, and 

 probably in others, results of considerable interest have arisen. 

 At the present moment I am only in a position to speak de- 

 finitely as to one object, viz. this star 6 Cygni B = 22486. 



My attention was directed to the star from the circumstance 

 that the reconnoitring observations indicated a probable parallax, 

 and I determined to observe it systematically. The observations 

 were made on 33 nights, the first being November 30, 1879, and 

 the last being December 22, 1S81, observations of the distance 

 and of the position angle now submitted. The mean value of 

 the parallax from the distances is — 



+ o" - J04 ± - o6o, 

 and from the positions 



+ o"-383 ± -130, 

 the mean being 



+ o" .4S2 ± o"'054. 

 It is a matter of considerable interest to observe that this is 

 about the same parallax as that of 61 Cygni, another object in 

 the same constellation, and a double of the same character. 



The proposed part v. will consist of five papers, as follows : — 

 (1) Reconnoitring observations of 36S stars, with a view of 

 finding whether they have a large parallax ; (2) on the annual 

 parallax of Groombridge l6lS; (3) further researches on the 

 annual parallax of 61 Cygni ; (4) on the annual parallax of 

 P. III., 242 ; (5) on the annual parallax of 6 Cygni 6. 



Brief accounts of the results of 2, 3, 4 have already appeared in 

 the Proceedings of the Royal Irish Academy or in the special 

 astronomical journals. It is now proposed that they shall be 

 issued fully and with all the information necessary to enable 

 astronomers to judge them adequately. 



Besides this work, which I now submit as completed, there is 

 a large mass of other work which is in a partially completed 

 state. The red star Sch 249 (a) seems to have a parallax, and 

 I have completed two sets of observations thereon. These have 

 indeed been finished for some time, but I have nftt yet been able 

 to complete the discussion, and further observations will probably 

 be necessary. I have also completed 'wo sets which will give 

 four independent determinations of the parallax of u Cephei. 

 There are also some hundreds of the reconnoitring observations 

 in a half-completed condition, most of which I hope to observe 

 during the autumn. 



Up to the present I have almost entirely confined my work 

 with the South Equatorial to the researches on annual parallax 

 with which Dunsink is historically associated. I have, however, 

 after some hesitation, decided to co-operate in the proposal of 

 Mr. Gill, her Majesty's Astronomer at the Cape, to determine 



