514 



NATURE 



{_April I, li 



easterly viinds and severe weatlier which were experienced at 

 the time. Henry Toynbee, 



Marine Superintendent 

 Meteorological Office, London, March 27 



Extracts from Mdeorohgkal Log of the Ship " Tiuiarii," Capt. 



D. Fiillarton 

 18S6 March 15 ; Noon Position, Lat. 48° 31' N., Long. 8° 16' W. 



" A great many small land birds about us ; put about 60 into 

 a coop, evidently tired out." 

 1886 March 17 ; Noon Position, Lat. 48° 30' N., Long. 7° 34' W. 



" Over 50 of the birds cooped on the I5ih died, though fed. 

 Sparrows, finches, water wagtails, two different small kinds of 

 birds, names unknown to me, one kind like a linnet, and a large 

 bird like a starling. In all there have been on board over 70 

 birds, besides some that hovered about us for some time and fell 

 into the sea exhausted." 



Variable Stars 



I HAVE to express my indebtedness to Mr. Castell-Evans 

 (Nature, March 25, p. 486) for drawing my attention to Prof. 

 Meldola's valuable memoir of 1878. Occasionally I cannot 

 help passing over a paper of great interest ; and, much to my 

 regret, I did not read Prof. Meldola's until to-day. According 

 to his theory there is '•. . . actu.al combustion taking place in 

 the atmosphere of a slowly-cooling star previously at a tem- 

 perature of dissociation." The previous existence of elements is 

 assumed throughout the memoir ; and it is these which undergo 

 "actual combustion," and of course give rise to compounds 

 capable of the dissociation referred to. Prof. Meldola proceeds 

 to show that dissociation of compounds and actual combustion 

 of elements may very well lead to a "periodically unstable 

 chemical equilibrium." 



For my part I was not writing about combustion, but about 

 polymerisation ; not about compounds, but about elements ; and 

 nothing was said about dissociation. Chemical effect, more- 

 over, was expressed by an equation totally different in form 

 from dissociation equations. 



There is thus a perfect distinction between my work and that 

 of Prof. Meldola. He is, so far as I am aware, the originator 

 of the theory that the variability of a star may depend on actual 

 combustion of elements, followed by dissociation of compounds. 

 I regard this theory .as having considerable value, and great 

 probability. But it has obviously nothing whatever to do with 

 ray own. Edmund J. Mills 



Glasgow, March 27 



Colours in Clouds 



I AM afraid I cannot give any further details to .aid Mr. 

 Backhouse. My object was to point out that the presence of 

 coloured fringes is not very rare, though they require suitable 

 means to see them. 



I do not think the dark blue tone is very material. 

 Mr. Backhouse will, however, .'ee that it implies a general 

 absence of glare and illumination of the atmosphere in the 

 neighbourhood of the cloud, and that is exactly the condition 

 which I artificially made by a suitable dark glass, which stopped 

 the glare. It is the dilution of the tints with white light which 

 makes them faint or invisible. Of course it may be said that the 

 dark glass will weaken the tints as well as the general light, but 

 as a fact the tints do show better through a proper one, and 

 reduction of glare does make colour more marked. 



Nor do I think that the square or rhomboidal form is im- 

 portant, for I think that is only the result of the air-currents 

 which cause the light cloud. 



These colours will be oftener seen in projections from banks 

 near the horizon, if my view be correct of the height at which 

 they are formed, because it is only when the bank or mass of 

 thick cloud hiding the sun is low that we see well above it. 

 Mr. Backhouse gives enormous heights at which water could 

 only visibly exist as minute ice-crystals, such as cause halos. 



J. F. Tennant 



37, Hamilton Road, Ealing, W., March 27 



The Distribution of Appendicularia 

 In regard to Prof. Ilerdman's query concerning the distribu- 

 tion of Appcnd'u'utaria it may be mentioned that this form was 



frequently met with near the surface of the sea during the 

 observations for H.M. Trawling Commissioners along the east 

 coast of Scotland. From previous observations it would seem 

 to be prevalent, especially in summer and autumn, all round our 

 shores, as well as to stretch far into the neighbouring seas. 



W. C. MclNTOSH 

 St. Andrew's Marine Laboratory, March 23 



THE TECHXICAL INSTITUTE 

 T N considering the sixth .Annual Report of the Council 

 -*• of the City and Guilds of London Institute to the 

 Governors, we cannot but be impressed with the sub- ' 

 stantial advance made in each of the several branches of 

 the Institute's work. 



The past year has seen the completion of the great 

 Central Institution in Exhibition Road, the University of 

 the system of technical education, and London may be 

 congratulated on at last possessing an institution which 

 is, as pointed out in the Report, comparable with, and in 

 some respects superior to, a German Pot>technic School. 

 Considering the thorough manner in which the work- 

 shops and laboratories in the several departments have 

 been equipped, we think the Institute is justified in 

 claiming that parents will be enabled to secure in Eng- 

 land for their sons technical instruction of the same high 

 class as has been for so long provided in the great 

 technical colleges abroad, and moreover better adapted 

 to the special circumstances of home industry. The 

 Report further expresses a patriotic hope that students 

 trained in the Central Institution will gradually occupy 

 the places in manufacturing works, and especially in 

 chemical works, both in Great Britain and the colonies, 

 which have of late been almost monopolised by the 

 Germans and Swiss. 



Besides the regular courses of instruction, special series 

 of lectures are given by the Professors of the Institution 

 at 5 o'clock, and we have reason to know that such 

 courses as Prof Henrici's on the Differential and In- 

 tegral Calculus for engineering students, and those by 

 Prof Armstrong on Carbon Compounds, and by Prof. 

 Ayrton on Industrial Apphcations of Electricity, now 

 being given, fulfil a distinctly-felt want. The same may 

 also be said of the special courses, including that on 

 Iron-Girder Bridge Construction, by Prof. Unwin, to be 

 given in July. 



At the Finsbury Technical College the year has been 

 marked by the appointment of Dr. Silvanus Thompson 

 to the office of Principal, a post the duties of which have 

 hitherto been discharged by Mr. Philip i\Iagnus, the 

 Director and Secretary of the Institute, but which the 

 enormous increase in all the branches of the Institute's 

 work has compelled him to relinquish. It is satisfactory 

 to note that the great success already achieved by this 

 College, both with respect to its Day and Evening De- 

 partments, has continued, and the Institute has deter- 

 mined to considerably increase the accommodation at a 

 cost of 17,500/. In the Evening Department greater 

 prominence has been given to courses of instruction for 

 persons engaged in the various branches of the building 

 trade, laboratories for instruction in plumbing, in gas- 

 fitting, and in metal-plate work having been arranged, 

 as also a class for builders' quantities. There are now 

 between 600 and 700 persons attending the courses in the 

 Evening Department. 



The branch of its work by w^hich the Institute is most 

 widely known, the system of technological examinations, 

 develops rapidly. According to Mr. Magnus's present 

 Report, 396S candidates presented themselves for e.x- 

 amination in May last, of whom 2168, or nearly 55 per 

 cent., w-ere successful in passing. Examinations were 

 held in forty-two subjects. In four subjects incltided in 

 the programme, viz. salt manufacture, oils and fats, 

 silk manufacture, and mechanical preparation of ores, 

 the number of candidates was below the minimum for 



