208 



NA TURE 



[December 28, 1905 



OUR ASTRONOMICAL COLUMN. 



Comet 1905c. — The results of numerous observations of 

 comet 1905c (Giacobini) are published in No. 4058 of the 

 Astronomischc Nachrichten. Observing at Bamberg on 

 December 10, Prof. Hartwig recorded the magnitude of 

 this object as 100 and its diameter as 2'. 



The following is taken from an ephemeris published by 

 Herr E. Stromgren in No. 4060 of the Astronomische 

 Nachrichten : — 





. (true) 



h. 



S (true) 



logy 



9-8601 



97908 



log i Brightness 

 00312 .. 5 " 16 

 COI92 ... 7-51 



Dec. 28 ... 16 31 10 ... + 5 542 



,, 30 ... 16 46 19 ... + 3 45° 



Jan. 1 ... 17 2 3 ... + I 286 



„ 3 ... 17 iS 25 ... - o 567 



,, 5 ■•• "7 35 2 4 ■•■ _ 3 2 9'7 ■■ 97° 2 ° ■• 0014S ... 11*54 



Writing in the Daily Graphic, Mr. Denning states that 

 the comet is rapidly becoming brighter, and should become 

 visible to the naked eye early next month. On January 6 

 the comet will be about fourteen times as bright as when 

 discovered. 



Eclipse Spectra. — At the meeting of the Paris Academy 

 of Sciences held on December 11, M. Salet submitted 

 further, and more detailed, results of the discussion of the 

 spectrograms obtained by him during the recent eclipse of 

 the sun. 



Two spectroscopes were employed, the one arranged for 

 photographing the visual part of the spectrum, the other, 

 made up of quartz and Iceland-spar optical parts, for 

 photographing the ultra-violet end. 



The slits of the spectroscopes were adjusted so that they 

 bisected the solar images produced by two heliostats and 

 collimators. On the one side of the sun the slit cut 

 through an important group of prominences, and the result- 

 ing spectrum shows a number of lines, including those due 

 to II, Ca, coronium, and He, and a line at \ 4025 to 

 which no origin has as yet been assigned. On the other 

 limb of the sun the spectrum shows only the lines due to 

 coronium and the H and K (calcium) lines. 



Of all the lines found, M. Salet believes that only the 

 coronium line is truly coronal ; this extends to about 4' 

 above the sun's limb, but does not descend to it, whilst 

 the lines of other elements are strongest next to the limb, 

 and are much shorter than the coronal line. 



Twenty-two lines have been measured in the ultra-violet 

 spectrum obtained — which extends to A 308, and is very 

 rich in bright lines — and of these eight are coincident with 

 strong titanium lines in the ordinary solar spectrum 

 (Comptcs rendus, No. 24). 



Ionisation of the Atmosphere during Total Solar 

 Eclipse. — The results of the researches on the ionisation 

 of the atmosphere during the eclipse of August 30, which 

 were obtained by M. Charles Nordmann at Philippeville, 

 are published in No. 23 (December 4) of the Comptes 

 rendus. 



Until about forty-live minutes after the first contact, the 

 curve registered by the ionograph was of the regularly 

 increasing type, such as was obtained on every day when 

 the sky was clear. But at that time an unusual pro- 

 gressive recession took place, culminating in a sharply 

 marked minimum forty minutes after totality, and this was 

 followed by a gradual increase in the ionisation until, at 

 about twenty minutes after the last contact, the curve 

 assumed its normal height. 



It thus appears from this research that the solar radi- 

 ation is one of the factors on which the ionisation of the 

 atmosphere depends, a result which accords with the hypo- 

 theses formulated by Lenard, Elster and Geitel. 



The amount of the " lag " of the ionisation curve behind 

 the related ellipse phenomena is also in accordance with 

 theory. 



Mi isi res of Double Stars. — The Greenwich results "f 

 micrometer measures of double stars during the year 1004 

 are published in No. 1, vol. lxvi., of the Monthly Notices 

 The observers were Messrs. Lewis, Furner, and Bowyer, 

 and the observations were made with the 2.s-imh refractor 

 '38 leet focal length), a power of 670 being general'} 



NO. 1887, VOL. 73] 



employed. About 430 stars were measured, some of them 

 on several nights, and the table given shows the coordin- 

 ates (1900), the position angle, the distance, the magnitude, 

 and the epoch of the observation of each pair. 



Graphical Method for finding the Time of Moon- 

 rise. — In No. 10, vol. xiii., of Popular Astronomy, Fr. 

 W. F. Rigge, S.J., of Creighton University (Nebraska), 

 gives and explains a set of curves which may be used for 

 finding the times of moonrise and moonset, on any future 

 date, employing a graphical method which he believes has. 

 not been previously published. Three curves are necessary, 

 one to determine the time of the moon's meridian passage, 

 the second to give its hour-angle, and the third to obtain 

 the correction to the rising and setting, due to the moon's 

 motion in right ascension. 



The correct result is easily obtained to within an accuracy 

 of one minute, and the author states that he is able to 

 compute the times of both rising and setting, for a whole 

 month, in less than an hour. 



NEW BUILDINGS OF THE GLASGOW AND 

 WEST OF SCOTLAND TECHNICAL COLLEGE. 



THE first section of the new buildings of the Glasgow 

 and West of Scotland Technical College was formally 

 opened on Thursday, December 21, by the Right Hon. 

 [ohn >imlair, M.P., Secretary for Scotland. The opening 

 ceremonv took place in the examination hall, and was 

 attended' by a large and representative assembly. The 

 chairman o'f the governors, Mr. Win. Robertson Copland, 

 presided, and in introducing Mr. Sinclair gave several 

 details iluit are of general interest. The part of the build- 

 ing in •■ completed and occupied represented about 70 per 

 cent, of the whole scheme, and even in its uncompleted 

 state was the largest of the kind in Great Britain. The 

 floor area of the completed part extended to more than 

 187,000 square feet, or about four and one-third acres; the 

 corridors in the building measured more than a mile in 

 length ; and there were 828 windows which required one 

 acre and one-third of glass to fill them. The cost of 

 the completed part was 211,743/., and was fu "- v met . b >" 

 subscriptions already paid or by sums about to fall in. 

 Although all the principal classes were now accommodated 

 in the new buildings, there were still several industrial 

 classes — for decoration, furniture design, printing, litho- 

 graphing, and the like— that would have to be conducted 

 in rooms outside the college. It was also pointed out that 

 since the demand for new buildings became clamant about 

 ten years ago, the increase in the number of day and 

 evening students combined had been about 50 per cent. ; 

 last session, 1904-5, the day students numbered 530 and 

 the evening students 4490. 



The Secretary for Scotland said it was a very high 

 privilege to be associated in any degree with so important 

 a work. Nobody who knew anything of Glasgow or tin- 

 west of Scotland and looked round that assembly, both on 

 the platform and before him, could fail to recognise thai 

 an occasion which brought together the leading men in 

 so many different spheres of activity was an occasion oi 

 special importance. That fact had been emphasised by 

 the figures which the chairman had given them in con- 

 nection with the technical college, and it must be a special 

 gratification to the governors of the college that public 

 appreciation of their work was so evident in the attend- 

 ance of leading men that afternoon. As he understood 

 it, this great institution was spei ially fortunate in carry- 

 ing on an ancient tradition — a tradition dating from Prof. 

 Anderson, a man who seemed to have been curiously 

 modern in some of his ideas ; and it must be a source of 

 strength to that institution that it had so venerable a 

 tradition to support and so wide a field of modern activity. 

 No one would dispute henceforth, if they had been inclined 

 to dispute it hitherto, that Glasgow and the west "I Scot- 

 land generally, in the erection of that great building, in 

 the size and selection of the staff, and in the growing 

 attendance oi the students, had shown a lively recognition 

 1 I the value of such work as was done in that institution. 

 As the chairman had pointed out, the plans of himself and 

 the board of governors had not been fullv attained ; he 



