March 20, 19 19] 



NATURE 



53 



and information concerning a number of subjects of 

 public interest, including, inter alia, such questions as 

 (i) the economic aspects of coal production in Great 

 Britain, (2) low-temperature distillation of coal, 



(3) future standards for public gas supplies, and 



(4) the proposed electric power scheme, etc., and 

 invites individuals, firms, or institutions who fnay 

 possess information of value to place it at the disposal 

 of the Committee. All communications should be 

 addressed to Prof. W. A. Bone at the Imperial Col- 

 lege of Science and Technology, South Kensington. 



We regret to record the death on February 28, in 

 his fifty-eighth year, of Mr. F. C. Forth, principal of 

 the Municipal Technical Institute, Belfast. Mr. Forth 's 

 death has removed from that city, and from Ireland 

 generally, a- potent force in the promotion of scientific 

 and technical instruction and training. On the passing 

 of the Agriculture and Technical Instruction (Ireland) 

 Act of 1899 the Corporation of Belfast took immediate 

 steps to inquire into the facilities for technical instruc- 



iim existing in Belfast and found them totally in- 

 adequate, only five institutions existing with some 

 -even or eight hundred students enrolled. It there- 

 upon decided to appoint a principal and director of 

 it'chnical instruction and to prepare a scheme for a 

 new building, and in 1901 Mr. Forth, then vice- 

 principal of the School of Technology, Manchester, 

 took up the post. An admirable site was secured, 

 and with the aid of the new principal, whose know- 

 ledge and experience gained in Manchester proved 

 t)f singular service, a splendid building, standing on 

 upwards of 5000 square yards in one of the prin- 

 cipal avenues of Belfast, was erected, calculated to 

 serve the best interests of the great engineering, tex- 

 tile, and other industries of the city. The foundation- 

 stone was laid in November, 1902, and the building 

 opened by the Lord-Lieutenant in 1907 ; and the 

 institute has now an enrolment of 7000 individual 



indents, Mr. Forth was a born teacher and 



rt,faniser, able to infuse his enthusiasm into both 

 students and colleagues. In 1915 he was elected 

 a fellow of the Royal College of Science, Ire- 

 land, "in consideration of the manner in which, 



hrough vour work as an educationist in the 

 Id of technical instruction, you have contributed i 



-■ the advancement of science in Ireland." At 

 a special meeting of the Library and Technical In- 

 struction Committee of the Belfast Corporation a 



• solution was passed recording its sense of the 

 lofound loss sustained by the corporation and the 

 uv generally in the death of the highly esteemed and 



• illiantlv successful principal of the Municipal Tech- 

 ical Institute, Mr. F. C. Forth. 



A MEETING of the Illuminating Engineering Society 

 on February 25, when the lighting of railways was 

 discussed, was attended by representatives of a number 

 of the leading railways. Mr. A. Cunnington, lighting j 

 engineer to the London and South- Western Railway, 

 who read the introductory paper, remarked that by 

 the aid of available experience tentative standards for 

 the lighting of platforms, goods sheds, and goods \ 

 yards could now be formulated. Stations were divided 

 into three classes, the specified illumination being 

 05, 025, and 0035 foot-candle respectively, measured 

 in a horizontal plane 3 ft. above the platform. In 

 goods sheds, values about twice as high were sug- 



fested. A number of special installations were 

 escribed, including corridors, parcels offices, and 

 signal-boxes. In the discussion, the importance to 

 railwav companies of employing an expert in lighting 

 to deal with all problems connected with illumination 

 was strongly emphasised. 



NO. 2577. VOL. 103] 



OUR ASTRONOMICAL COLUMN. 

 Photo-electric Determinations of Stellar Magni- 

 tudes OF Planets.— ;4str. Nach., No. 4976, contains a 

 paper by P. Guthnick on the application of this verv 

 accurate method to the determination of the stellar 

 magnitudes of Saturn and Mars. The individual results 

 show that the probable error of a determination is in 

 the neighbourhood of 00 im. The results of a com- 

 parison of Saturn with Pollux are given for four op- 

 positions ; after allowing for the changing aspect of the 

 ring they are practically constant, and show that without 

 the ring the planet is just 1/3 mag. brighter than 

 the star. As two of the oppositions were at sun-spot 

 minimum and two at maximum, the inference is also 

 drawn that there is no sensible variation of sunlight 

 in the course of the cycle. Very numerous comparisons 

 of Mars with standard stars were made; the results 

 are grouped according to longitude of central meri- 

 dian, and show that the planet is variable to the 

 extent of 1/6 mag., according to the portion presented 

 to us. The light-curve obtained is consistent for the 

 same opposition, but varies from one opposition to 

 another with the different pose of the planet's equator 

 and the amount of snow or cloud that is present on 

 the disc. 



Nova Aquil^.— The Monthly Notices of the Royal 

 Astronomical Society for December last contains 

 papers on this nova's spectrum by the Rev. A. L. 

 Cortie and Dr. J. Lunt. The former reproduces six 

 spectra photographed in June and July, which illus- 

 trate the development of the hydrogen bands. Both 

 papers give wave-length tables and identifications; 

 lines due to iron, titanium, chromium, scandium, 

 barium, helium, calcium, etc., are identified. Both 

 also note that the line-of-sight velocities fall into 

 two groups, one of the order of -1500 km. /sec, the 

 other of the order of -800 km. /sec. 



The same issue of the Monthly Notices contains a 

 paper by Dr. A. A. Rambaut on the visual magni- 

 tudes of the nova from June 9 to December 10; the 

 table shows a well-marked periodic variation with a 

 period of eleven days during July and August; after 

 correcting for the progressive decline, the range from 

 maximum to minimum was just half a magnitude. 



The \'ariables of Long Period. — Many astro- 

 nomers have of late inclined to the theorv that the 

 red variable stars, of types M aj;id N, are dwarf stars, 

 near the end of their career as suns, on which an 

 incipient crust is forming. Mr. W. Gyllenberg, of the 

 Lund Observatory {Arkiv for Matematik, Astronomi 

 och Fysik, K. Svenska Vetenskapsakademien, 

 Band 14, No. 5), examines the question of their dis- 

 tances by means of their proper motions. Contrarv 

 to the above dwarf theor>', he finds that the stars are 

 very distant, and must be classed as giants, their 

 mean absolute magnitude at maximum (at a distance 

 of 10 parsecs) being -065, making them comparable 

 in absolute lustre with stars of the types B8 to .A2. 

 The mean velocity in all directions comes out as 

 377 km. /sec, in admirable accord with the value 

 364 found by Mr. Paul W. Merrill (Astrophysical 

 journ., xli., 247) from motions in the line of sight. 



.'\dopting the above mean absolute magnitude, and 

 plotting the distances of the stars from their bright- 

 ness, they show greater extension in the galactic 

 plane than perpendicular to it, which confirms the 

 conclusion that they are distant. The denser parts of 

 the system extend to 3000 L.Y. in the plane, 1000 L.Y. 

 perpendicular to it. The distances found for the M 

 variables accord well with those previously found for 

 non-variable giant stars of type M. It thus appears 

 that long-period variability is an incident in the early 

 historv of star-life. 



