68 



NATURE 



[November 15, 1900 



and other equatorials have only been used on special occasions 

 and for visitors, 594 of whom inspectednthe observatory during 

 the year. 



The automatic photographic registration of terrestrial magnetism 

 was obtained with only 34 hours interruption during the year ; 

 absolute measurements were made on seven occasions, and in- 

 strumental constants, &c. determined. 



The series of cloud photographs has been continued, 77 

 additional pairs of plates being taken from the roof of Parliament 

 House and the observatory grounds respectively. These are 

 now being measured and discussed in connection with visual 

 observations. 



Abnormal Stars in Clusters. — Prof E. E. Barnard has 

 .for some time been engaged in micrometrical determinations of 

 the positions of a number of the individual stars in the great 

 globular clusters M 3, M 5, M 13, M 15, and M 92, and in the 

 course of the work has noticed several peculiarities, the most 

 striking of which is the fact that some of the stars in these 

 clusters shine with a much bluer light than the majority of their 

 neighbours, thus producing a remarkable difference between 

 their photographic and visual magnitudes. So striking is this 

 that the images in some cases are so large as to suggest variability 

 {Astrophysical Journal, vol. xii., pp. 176 — 181). Comparisons 

 have been made with a negative enlarged four times from an 

 original of M 13 Herculis, taken with the Potsdam 13-inch 

 photographic refractor in 189 1. 



The two stars, Nos. 148 and 131 of Scheiner's catalogue of 

 this cluster are practically equally bright to the eye as seen in 

 the sky; but on the photograph No. 148 has an image four or 

 five times larger than No. 131. 



Other neighbouring stars, however, register photographically 

 the same relative brightness as determined visually. This led 

 to the minute examination of No. 148 with high magnifying 

 power, when it gave the impression of some object less sharp 

 than stars near it, suggesting the idea of a small planetary 

 nebula. Other stars showing the same abnormal features are 

 detailed, and a numbered sketch of a portion of the cluster given 

 for identification. 



Prof. Barnard says he has found similar cases in other 

 clusters, e.g. M 5 Librae. A suggestion by Prof. Hale that a 

 photograph taken through a yellow screen should not show 

 these peculiarities was tested on the 40-inch Yerkes refractor and 

 proved correct, the stars previously mentioned coming out on 

 the photograph with almost the identical relative brightness they 

 show visually in the; same telescope. 



The suggestion is made that these stars are of similar nature 

 to the condensation or nucleus of the annular nebula in Lyra, 

 perhaps bearing the same relation to the other stars of the cluster 

 that the nucleus of that nebula does to the ordinary stars of the 

 sky. It would appear, therefore, that the possibility of these 

 abnormal stars being of the nature of nebulce brings up again 

 the question of nebulosity in the globular clusters. 



Recent Studies of Infra-red Region of Solar Spec- 

 trum. — In the current issue of the Comptes rendus (vol. cxxxi. 

 pp. 734-736), Prof S. P. Langley describes the result of his 

 recent work on the bolometric study of the solar spectrum in the 

 infra-red. At the date of his last communication to the French 

 Academy, in 1894, the knowledge of the region beyond \ = ifx was 

 very imperfect, but now, thanks to the great improvement of his 

 bolometer, which is capable of detecting a variation of tempera- 

 ture as minute as the millionth part of a degree, the map of the 

 calorific rays has been carried to A, = 5*8)u. The article is illus- 

 trated by a heliogravure of the calorific spectrum from A. =076/11 

 to A. = S'3m, both the galvanometer record and the "line" in- 

 tegration being given. More than 600 lines are recorded, each 

 of which has been studied separately and obtained by from six 

 to twenty independent observations. Prof. Langley calls special 

 attention to the observations of the telluric infra-red spectra, 

 which have been studied during all seasons from 1895-1900. 

 Systematic variations have been observed in them which appear 

 to have some relation to the season in which they occur, and, 

 although small, are very distinct. 



The Zodiacal Light. — The Observatory for November 

 contains the first part of an article giving in a concise form 

 the complete history of the zodiacal light. In this number 

 the history is brought up to the year 1855, being derived mainly 

 from two sources ; (i) the article by M. E. Lefebure in Ciel et 

 Terre, April, 1894 ; (2) a Review by Prof. C. E. Brame in the 

 Popular Science Monthly, October, 1877. 



THE NAPLES ZOOLOGICAL STATION.^ 



'T'HE Zoological Station at Naples is so well known, either by 

 personal experience or by repute, to zoologists the world 

 over, that it may seem to some that any further account of it is 

 quite unnecessary. But the institution has lately extended its 

 scope and increased its equipment so as to appeal to workers in 

 other lines of biology ; and, moreover, as certain Associations 

 and Universities in this country and elsewhere give annual 

 grants towards defraying the expenses of special researches at 

 Naples, it is due to scientific men in general that they should be 

 kept informed from time to time of the conditions under which 

 such work is carried on. 



About ten years ago the then chairman of the British Asso- 

 ciation Naples Committee visited Naples, and gave an interesting 

 report (Nature, February 1891, p. 392) on the condition of 

 the Zoological Station, in which he dwelt mainly upon the 

 history, constitution, finance and publications ; it will, there- 

 fore, be best that I should now draw attention chiefly to the 

 present facilities for work at this world-renowned laboratory, 

 and to the additions and improvements effected during the last 

 decade. I am indebted to Prof. Dr. Anton Dohrn, the director, 

 and to the secretary, Mr. Linden, for much information given 

 me during my recent visit. 



Since Dr. Sclater's visit in 1890 additional accommodation 

 has been obtained by a re-arrangement of the roof of the main 

 building. This gives space for a second laboratory, a supple- 

 mentary library, and various smaller rooms used as chemical 

 and physiological laboratories, for photography and bacteriology. 

 A good deal of the research in recent years, both on the part of 

 those occupying tables and of the permanent stafiF, has been 

 in the direction of comparative physiology, experimental em- 

 bryology, and the bacteriology of sea-water, and all necessary 

 facilities for such work are now provided. 



The number of work-places, in some cases separate rooms, 

 known technically as "tables," is about fifty-five, and of these 

 about thirty-four are rented annually by States, Universities, or 

 Associations. Germany takes about ten of these, and Italy 

 seven. There are three American tables, and three English 

 (rented by the Universities of Cambridge and Oxford and the 

 British Association respectively) ; consequently there are generally 

 about half a dozen English and American biologists at work in 

 the station ; but Dr. Dohrn interprets in a most liberal spirit 

 the rules as to the occupancy of a table, and, as a matter of 

 fact, during my recent visit there were, for a short time, no less 

 than three of us occupying simultaneously the British Association 

 " table," and provided with separate rooms. 



A work-table is really a small laboratory fitted up with all 

 that is necessary for ordinary biological research, and additional 

 apparatus and reagents can be obtained as required. The 

 investigator is supposed to bring his own microscope and dis- 

 secting instruments, but is supplied with alcohol, acids, stains, 

 and other chemicals, glass dishes and bottles of various kinds 

 and sizes, drawing materials and mounting reagents. Requi- 

 sition forms are placed beside the worker on which to notify his 

 wishes in regard to material or reagents, he is visited at frequent 

 intervals by members of the staff, and all wants are supplied in 

 the most perfect manner. The recent addition of carefully 

 planned filter-beds, by means of which half the sea-water in 

 circulation in the tanks can be filtered and separated from the 

 rest, has materially increased the facilities for some classes of 

 experimental work. 



The staff of the station consists of : — 



(i) Dr. Anton Dohrn, the founder and director. 



(2) Seven or eight scientific assistants — viz. Dr. Eisig, ad- 

 ministrator of the laboratories ; Dr. Paul Mayer, editor of the 

 publications ; Dr. Giesbrecht, assistant editor and supervisor of 

 plates ; Dr. Gast, assistant editor and supervisor of microscopic 

 drawings ; Dr. Schdbel, librarian ; Dr. Lo Bianco, administrator 

 of fisheries and preparateur ; Dr. Hollandt, temporarily in 

 charge of the microscopic sections department — all of them 

 well-known men, each eminent in his own line of investigation. 

 The post of assistant in the physiological department, formerly 

 held by the late Dr. Schoenlein, is now vacant. 



(3) In addition to the foregoing there are : — The secretary, 

 Mr. Linden ; two artists and the engineer. 



(4) Also about thirty attendants, collectors and others em- 



1 Abridged from the " Note by the Chairman" of the Naples Committee 

 - in the report presented to the British .Association at Bradford, September 



NO. l6:?D, VOL. 63] 



