354 



NATURE 



[August 7, 1890 



a representation of the Place du Vieux Marche at Rouen (the 

 piece being Jeanne d'Arc), and, as it is strongly illuminated, 

 at a given moment, from the centre, the light outside being 

 low, a spectator at any point has an excellent view of the 

 5Cene, while seeing nothing of the crowd beyond. 



The additions to the Zoological Society's Gardens during the 

 past week include a Malbrouck Monkey {^Cercopithecus cyno- 

 surus 6 ) from West Africa, presented by Miss Florence 

 Schuler; an American Black Bear {Urstis americanus) from 

 Canada, presented by Mr. John Sands ; a Common Otter {Lutra 

 ■vulgaris) from Ross-shire, presented by the Hon, J. S. Gathorne 

 Hardy, M.P., F.Z.S; two Cape Doves {(Ena capensis) from 

 South Africa, presented by Miss Grace Debenham ; two 

 Imperial Eagles {Aquila imperialis) from Spain, presented by 

 Mr. Walter Buck ; two Smooth Snakes [Coronella Icevis) from 

 Hampshire, presented by Mr. E. Penton, F.Z.S; a Hairy 

 Armadillo {Dasypus villosus) from La Plata, a Greater Sulphur 

 Crested Cockatoo {Cacatua galerita) from Australia, deposited ; 

 five , Common Peafowls {Pavo cristatus), six Ring-necked 

 Pheasants {Phasianus torquatus), three Gold Pheasants (Thau- 

 malea pida), five Silver Pheasants {Euplacamus nycthemerus), 

 ■seven Californian Quails {Callipepla californica), a Vulpine 

 Phalanger {Phalangista, vulpina ? ) bred in the Gardens. 



OUR ASTRONOMICAL COLUMN. 

 Objects for the Spectroscope. 



Sidereal Time at Greenwich at lo p.m. on August 7 

 igh. 5m. 29s. 



Remarks. 

 (ij This cluster is thus described in the General Catalogue : 

 " A globular cluster ; bright ; large ; irregularly round ; gradu- 

 ally very much compressed in the middle ; easily resolved." 

 Dr. Huggins has observed that the spectrum is continuous, with 

 ^*a suspicion of unusual brightness in the middle," but he ap- 

 parently made no attempt to determine the position of the 

 brightness. Such a maximum of light in one part of the spec- 

 trum is suggestive of radiation phenomena, though of course it 

 is possible that it may be simply a contrast effect due to the 

 presence of dark lines or bands. In any case trustworthy mea- 

 sures may give some clue to the constitution of the stars of 

 which the cluster consists. 



(2) The G.C. description of this object is as follows : " Con- 

 siderably bright ; small ; irregularly round ; easily resolvable." 

 It is thus apparently an undoubted cluster, and it is therefore 

 very remarkable that Dr. Huggins records : " I believe that the 

 spectrum consists of one bright line." If this be confirmed, the 

 object must evidently be a cluster of " nebulous stars," and 

 resolvability can no longer be a criterion for non-nebulosity." 



(3) Duner describes the spectrum of this star as a feebly-deve- 

 loped one of Group II. ; only the bands 2, 3, and 7 being seen. 

 As the complete series of bands has been recorded in stars of 

 much smaller magnitude with the same instruments, it is clear 

 that there are decided specific differences. A more detailed 

 -examination, with special reference to the presence or absence of 

 bright lines or flutings and dark lines, is suggested. 



(4 and 5) These are stars of the solar type and of Group IV. 

 respectively. The usual observations are required in each case. 



(6) The spectrum of this star is one of Group VI. The dark 

 1:5ands are strong, but the blue zone is very feeble. Further 

 details should be looked for. 



(7) This variable has a spectrum of Group II., and the ap- 

 proaching maximum of August 15 may be utilized for ascertain- 



NO. 1084, VOL. 42] 



ing whether, in common with other variables of the same group, 

 bright lines appear at or near maximum. The magnitude at 

 maximum appears to vary between 6-6 and 77, whilst that at 

 ininimum is about 11-5, the period being about 408 days. The 

 line of hydrogen at G is apparently the most easily seen in this 

 class of objects. The bright flutings of carbon should also be 

 carefully observed as the star fades. A. Fowler. 



Catalogue of Red Stars. — No. V. of the Cunningham 

 Memoirs of the Royal Irish Academy contains a new edition of 

 Birmingham's " Catalogue of Red Stars," by the Rev. T. E. 

 Espin. The work undertaken by Mr. Espin is (i) the observa- 

 tion of such stars of Mr. Birmingham's Catalogue as seemed to 

 merit special attention ; (2) a search for new red stars ; (3) the 

 spectroscopic observation of all stars not previously observed 

 with the spectroscope. This comprehensive programme was 

 Commenced about four years ago, and much important work has 

 been done under each of the heads. The original catalogue con- 

 tained ruddy ahd orange stars in addition to those having a 

 decided red colour, but these are now given in a separate list. 



In some remarks on the spectroscopic observations of the stars 

 in the Catalogue, Mr. Espin brings forward "one of the most 

 striking examples of the disagreements among spectroscopic 

 observers," viz. the difference between the spectrum of 152 

 Schjellerup as observed by Secchi and Dr. Huggins. The former 

 observer remarked that the dark zones coincided with the car- 

 bon flutings given by an alcohol flame. Dr. Huggins made the 

 comparison, and, either from imperfect instrumental conditions 

 or a different comparison spectrum, found there was no such 

 coincidence, although later observations, by Vogel, Duner, and 

 others, have established Secchi's view. 



A useful list is given of stars with bright lines in their spectra 

 discovered up to the date of publication, and no one has worked 

 more assiduously in this direction than Mr. Espin himself. After 

 an admirable and extended account of the discovery and the 

 spectra of these stars the following conclusions are arrived at : — 



(1) That in stars of type \.c (Group I.) where the hydrogen 

 lines and D3 are bright, the lines vary, and this variation is not 

 simultaneous. 



(2) That in stars with type III.c one or more of the hydrogen 

 lines may be brilliant and the others invisible, as in Mira, where 

 7 and S were conspicuous, but there was no trace of e and F. 



(3) In the cases of R Andromedte, R Cygni, and S Cassio- 

 peise, the extremely brilliant F line was detected after the 

 maximum. 



(4) In Vogel's type \.b, the hydrogen lines may really be 

 faintly bright, and in one of the stars of this class the existence 

 of other bright lines is proved, and they will hence, probably, 

 be found in others. 



It should be remarked that the stars of Group II. which have 

 bright lines in their spectra {e.g. Mira Ceta) are classified by 

 Mr. Espin as a new type, III.c. 



The total number of stars contained in the Catalogue is 1472, 

 of which 766 are given in the red star catalogue, 629 in the 

 list of ruddy stars, and 77 in an addendum. Besides these there 

 are 52 "bright-line" stars. Seven new variables were detected 

 by Mr. Espin during the four years of observation, and he 

 concludes that the work of discovering new red stars in the 

 northern heavens is complete as far as magnitude 8*5. Every 

 spectroscopist appreciates this valuable and important Catalogue, 

 and Mr. Espin is to be congratulated on having been able to 

 complete it in so short a time. 



Ancient Eclipses. — In the Astronomical Journal, No. 

 220, Mr. John Stockwell continues his discussion of the secular 

 and long-period inequalities in the moon's motion. The follow- 

 ing are the dates of the sixteen eclipses that have been investi- 

 gated, and some particulars referring to them. 



I. This eclipse is mentioned by Halley, by William of 

 Malmesbury, and in the Saxon Chronicle. It is shown that 

 the line of central eclipse passed over Cambridge. 



